Polar Coasts

3.10

Polar Coasts

DL Forbes, Geological Survey of Canada, Bedford Institute of Oceanography, Dartmouth, NS, Canada; Memorial University of Newfoundland, St. John’s, NL, Canada JD Hansom, University of Glasgow, Glasgow, UK Crown Copyright © 2011 Published by Elsevier Inc. All rights reserved.

3.10.1 3.10.1.1 3.10.1.2 3.10.1.3 3.10.2 3.10.2.1 3.10.2.2 3.10.3 3.10.3.1 3.10.3.2 3.10.3.3 3.10.3.4 3.10.4 3.10.4.1 3.10.4.2 3.10.4.3 3.10.4.4 3.10.5 References

Introduction Cold Coasts (Polar and Subpolar) Ice as the Distinguishing Feature of Polar and Subpolar Coasts Relative Sea-Level Trends on Polar Coasts Arctic and Antarctic Coastal Geomorphology Arctic Coastal Geomorphology Antarctic Coastal Geomorphology Polar Shore Processes Polar Glacial Processes: Ice Sheets, Tidewater Glaciers, and Ice Shelves Polar Marine Processes: Sea Ice and Shore Ice Erosion and Sedimentation Processes on Polar Coasts Coastal Permafrost and Erosion of Ice-Rich Shores Morpho-Sedimentary Features of Polar Coasts Ice-Bound Shores Transgressive Coastal Plain Shores Polar Deltas Polar Coastal Marshes Summary and Conclusions

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Abstract Polar and subpolar coasts are distinctive because of extreme seasonality and the presence of ice (predominantly tidewater glaciers, ice shelves, sea ice, and ground ice). Sea ice plays a protective role but may be either erosional or constructive when mobile. Wave activity, though effective mainly during the short summer, imposes a strong morphological signature on most sedimentary coasts. Unlithified coasts in permafrost are widespread on the Arctic Coastal Plain, where combined thermal and mechanical processes promote rapid erosion in ice-rich deposits. Antarctic and sub-Antarctic coasts are mainly dominated by rock or ice, as are parts of the Arctic coast.

3.10.1 Introduction 3.10.1.1

Cold Coasts (Polar and Subpolar)

The Earth’s high latitudes are characterized by low mean annual temperatures and strong seasonality in solar radiation, temperature, wind, precipitation type, and sea-surface condi­ tions. Geomorphic processes that are influenced or driven by low-temperature effects (periglacial processes) contribute to the formation of distinctive landscape features, including coastal landforms with characteristics not found at lower lati­ tudes. Nevertheless, freezing conditions during winter and the occurrence of sea ice as far south as 45° N in the northwest Pacific and northwest Atlantic lead to the formation of distinc­ tive cold coast features over a wide range of latitude (Forbes and Taylor, 1994). In the Southern Hemisphere, the moderat­ ing influence of the Southern Ocean and limited extent of land in the mid-latitudes restrict the development of cold coast features to the Antarctic continent and its sub-Antarctic islands (such as South Georgia, the South Orkney Islands, and the South Shetland Islands). This chapter focuses on Arctic and Antarctic coasts (Figures 1 and 2), including some sub-Arctic and sub-Antarctic shorelines, but for the most part does not extend to cold temperate coasts.

A small number of recent circumpolar reviews of this topic are available. For the Arctic, these include encyclopedia con­ tributions by Walker (2005a, 2005b) and Forbes (2005) and more focused papers by Walker (1998), Rachold et al. (2000, 2005), and Lantuit et al. (2008b, 2009), as well as work on Arctic coastal forcing (Atkinson, 2005). For the Antarctic, they include Gregory et al. (1984), Hansom and Gordon (1998), Bird (2003), Hansom (2005a), McMinn (2005), and Kirk (2010). Impacts of changing climate on Arctic coastal systems have been recognized in international assessments such as the Arctic Climate Impacts Assessment (ACIA, 2005) and the State of the Arctic Coast 2010 report (Forbes, 2011) but no such analysis yet exists for Antarctic coasts.

3.10.1.2 Ice as the Distinguishing Feature of Polar and Subpolar Coasts Besides the strong seasonality, the distinguishing feature of polar and subpolar coasts is the importance of ice in a variety of forms, including tidewater glaciers, ice shelves, sea ice (anchor ice, fast ice, and drift ice), and ground ice in permafrost (Figure 3). Occasionally, other forms of ice occur, such as river

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Figure 1 Arctic Ocean and surrounding seas, showing areas of active glaciation and a selection of place names mentioned in the text. Physiography (CAVM, 2003) for ice-free areas north of the tree line.

icings extending to the coast (Reimnitz and Wolf, 1998) or icings on tidal flats (Allard et al., 1998). Tidewater glaciers also occur on some temperate mountainous coasts, which are not considered polar. Glacial ice at the coast is discussed in an accompanying chapter (see also Chapter 3.07). Sea ice may play a protective role, limiting the development of surface waves during storms and acting as natural shore protection either seasonally or, in some areas, on a perennial basis (Taylor and McCann, 1976, 1983; Taylor and Forbes, 1987). Alternatively, dynamic sea-ice interaction with the shore may be destructive or constructive, depending on the situation, as ice-driven onshore can erode the backshore and damage infrastructure (Taylor, 1978; Kovacs and Sodhi, 1981), but may also nourish the shore zone through landward transport of nearshore sediments (Reimnitz et al., 1990). In the Arctic during the spring thaw, river discharge onto a frozen ocean may drain through cracks and sinkholes to create distinctive strudel scour depressions on the seabed that represent a hazard to pipelines (Reimnitz and Bruder, 1972; Leidersdorf et al., 2006). Many

other distinctive nearshore and beachface features attributable to shore ice on cold coasts are described later in the chapter (see also Forbes and Taylor, 1994; Byrne and Dionne, 2002). Most high-latitude coasts are developed in regions of con­ tinuous permafrost, where sediments are ice-bonded below a thin but variable seasonal thaw zone at the surface (the active layer) (Figures 4 and 5). In some places, permafrost extends into the nearshore and beneath the shelf (Mackay, 1972; Lachenbruch and Sass, 1982; Sellmann and Hopkins, 1983; Osterkamp. 2001; Romanovskii et al., 2003; Solomon et al., 2008). In pre-Holocene sediments that have been exposed subaerially for tens of thousands of years, ground temperatures <0 °C extend to depths of >1000 m in Yakutia (Overduin et al., 2007) and 400–850 m in the coastal lowlands and shelves of Siberia and northwestern Canada (Judge et al., 1987; Dallimore and Collett, 1995; Hinz et al., 1998; Todd and Dallimore, 1998). In areas of fine-grained sediments in the Arctic, there may be large proportions of excess ice, including locally large volumes of massive ice (Mackay, 1971, 1972; Aré,

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Figure 2 The Antarctic ice sheet (AIS), Antarctic ice shelves, and the major sub-Antarctic island groups, with 1000-m contours on the AIS Antarctic coasts free of ice are mapped but not discernible at this scale. From Antarctic Digital Database and other sources.

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Figure 3 Ice at the coast, a dominant factor in high-latitude coastal geomorphology, takes various forms: (a) debris-laden tidewater terminus of Neumayer Glacier, South Georgia; (b) ice at sea and onshore: coalescing retrogressive thaw flow failures in ice-rich deposits with snowmelt (nivation) on slope, mudflow transport across beach, wave-cut notch in backshore and ice push on beach, west coast of Banks Island, eastern Beaufort Sea, Canada; (c) ice ride-up on small barrier island, northwest coast of Banks Island, Canada; and (d) massive ice in coastal cliffs at Muostakh Island, east of Lena Delta, Laptev Sea, Russia. Photo sources: (a) JDH, 2003; (b-c) DLF, 2002; (d) courtesy Volker Rachold.

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Figure 4 Distribution of permafrost in the Arctic. C, continuous; D, discontinuous; S, sporadic; I, isolated. Data source: International Permafrost Association data base from Brown, J., Ferrians, O.J., Jr., Heginbottom, J.A., Melnikov, E.S., 1998. Circum-Arctic map of permafrost and ground-ice conditions. In: Parsons, M., Zhang, T. (Eds.), Circumpolar Active-Layer Permafrost System, Version 2.0. National Snow and Ice Data Center, Boulder (CD-ROM).

1980, 1988; Zenkovich, 1985). Erosion of ice-rich coasts occurs through a combination of mechanical and thermal processes (Aré, 1988; Forbes, 2005), resulting in the formation of dis­ tinctive coastal landforms. Much of the Antarctic coastal fringe is underlain by permafrost, as are areas exposed by retreating ice in the Holocene (Bockheim, 1995). In contrast to the Arctic, however, a lack of thick unlithified sediment in Antarctica limits the overall effect of frozen ground as an influence on coastal development.

3.10.1.3

Relative Sea-Level Trends on Polar Coasts

Rates of relative sea-level change vary widely across the Arctic, from rapidly emerging regions such as southern Hudson Bay and the Gulf of Bothnia to regions experiencing relative sea-level rise such as the western Canadian Arctic and northern Alaska. There are several factors that contribute to the rate of relative mean sea-level change at any one place: • the rate of global and regional sea-level rise; • the rate of local vertical crustal motion; • the gravitational fingerprinting associated with sources of meltwater to the oceans; and • ocean dynamic topography.

Global mean sea-level change results from changes in ocean volume caused by thermal expansion and the addition of melt­ water to the oceans (Milne et al., 2009). A major component of local (relative) sea-level change is the rate of vertical crustal motion, in particular the glacio-isostatic adjustment (GIA) result­ ing from glacial loading and unloading since the Last Glacial Maximum (LGM). The ICE-5G model (Peltier, 2004) provides reasonable estimates of the GIA on a global basis, although it overpredicts uplift in some areas such as southwestern Hudson Bay (James et al., 2010). An additional factor of great importance in the Arctic is the gravitational fingerprinting associated with meltwater contributions from various sources, given the proxi­ mity of many Arctic coasts to the large Greenland Ice Sheet as well as numerous glaciers and ice caps (Mitrovica et al., 2001; James et al., 2010). The gravitational attraction of a large ice mass tends to increase sea level in its vicinity; loss of ice mass produces a corresponding drop in sea level. For example, substantial melt­ water contributions from Greenland have the effect of decreasing the effective sea-level rise over much of the Arctic. Figure 6 shows the change in elevation over the past 500 years as a surrogate for the present rate of uplift or subsidence as depicted by the ICE-5G model for the circum-Arctic coast. The solid line depicts the locations of zero motion and the broken line the locations with 2 mm yr−1 uplift. Given that the global mean

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Figure 5 Distribution of observed permafrost in Antarctica with mean position of the –1 °C sea-surface isotherm. CR, Cape Ross; CA, Cape Adare. From Bockheim, J.G., 1995. Permafrost distribution in the Southern Circumpolar Region and its relation to the environment: a review and recommendations for further research. Permafrost and Periglacial Processes 6, 27–45.

sea-level rise has averaged 1.6–1.8 mm a−1 over the past 50 years (and assuming that similar rates prevail in the Arctic), it is clear that most of the Russian mainland coast from the Pechora Sea east is submergent at present (Proshutinsky et al., 2004, 2007; Whitehouse et al., 2007) – so too is the coast of northern Alaska and the western Canadian Arctic Coastal Plain (Andrews, 1989; Forbes et al., 2004), even when the effects of fingerprinting are taken into account. The pattern is more complicated over the central Canadian Arctic and Greenland. The outer fringe of Baffin Island and coasts on both sides of Lancaster Sound (northern­ most Baffin Island, Bylot Island, and eastern Devon Island) are areas of subsidence (cf. Dyke, 1979), as are parts of the Greenland coast (Figure 6). Through other parts of the Canadian Arctic as well as northern Greenland, ongoing uplift exceeds recent rates of sea-level rise, contributing to coastal emer­ gence. The 2 mm a−1 uplift contour in Figure 6 encompasses areas where the current uplift rate may be equaled or exceeded by present and future sea-level rise. With some of the higher projections of future sea-level rise published since the Fourth Assessment Report of the Intergovernmental Panel on Climate Change (IPCC, 2007), there is a potential for a switch to rising sea level by 2100 even in communities on the west coast of

Hudson Bay, where some of the most rapid uplift is occurring (James et al., 2010). The Antarctic coast is predominantly, if not entirely, emer­ gent (James and Ivins, 1998), with a measured uplift of 12 � 4 mm a−1 in Marie Byrd Land (Donnellan and Luyendyk, 2004) and up to 10 mm a−1 in the northern Antarctic Peninsula, but less in the south (Dietrich et al., 2004). Raymond et al. (2004) reported a measured uplift of 4.5 � 2.3 mm a−1 in the Dry Valleys. Emerged marine deposits are widespread around the continent and particularly in the sub-Antarctic islands, with the Holocene marine limit dependent on rebound and the tim­ ing of deglaciation at any given site (e.g., John and Sugden, 1971; Clapperton et al., 1978; Kirk, 1991; Goodwin, 1993; Berkman et al., 1998; Hall and Denton, 2000; Hall et al., 2004; Peterson et al., 2004; Bentley et al., 2007).

3.10.2 Arctic and Antarctic Coastal Geomorphology The Arctic has a vast extent of rock and sedimentary coasts, while 95% of the Antarctic coast is glacial and the remaining 5% is dominated by rock. Nonetheless, Arctic and Antarctic

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+ 2 mm yr−1 0 mm yr−1 16 mm yr−1 0 mm yr−1 +6 mm yr−1 90 E

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Figure 6 Rates of crustal uplift (average past 500 years, in mm yr ) from glacial isostatic adjustment (GIA) predicted by the ICE-5G 1.2/VM2 model (Peltier, 2004) for the Arctic circumpolar region. Solid line represents zero vertical motion due to GIA, broken line is uplift at 2 mm yr−1. Courtesy: Gavin Manson, GSC-Atlantic, 2010.

coasts share many characteristics: cold climate, permafrost, prevalence of varying durations and densities of sea ice, and exposure to storms during a variable but short open-water season. The fundamental difference between the Arctic and Antarctic regions lies in their geography: the Arctic is essentially a polar ocean basin capped by a thin skin of sea ice and surrounded by land (Figure 1), whereas the Antarctic is dominated by a pole-centered, high, and ice-covered continent

surrounded by a deep ocean (Figure 2). This has profound implications for climate, ocean circulation, sea-ice dynamics, coastal forcing, precipitation, hydrology, sediment supply, and a host of other issues relevant to coastal evolution and stability (Figure 7). The Arctic is characterized by many large rivers draining to the Arctic Ocean, whereas the Antarctic continent has abundant subglacial water contained in subglacial lakes but minimal surface runoff. Minor streamflow is locally effective

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Figure 7 North–south distribution of land area and mean surface air pressure, showing contrast between polar ocean in the north and polar continent (ice sheet) in the south. Mean surface air pressures are lowest in the South Polar Region, and this is also the area of strong westerly winds over the circum-Antarctic Southern Ocean. Redrawn from Dudeney, J.R., 1987. The Antarctic atmosphere. In: Walton, D.W.H. (Ed.), Antarctic Science. Cambridge University Press, Cambridge, pp. 193–149 taken from Hansom, J.D., Gordon, J.E., 1998. Antarctic Environments and Resources: A Geographical Perspective. Addison Wesley Longman, Harlow, 402 pp.

Polar Coasts

during the summer melt season, but the most substantial streamflow occurs in the lower latitudes of the Antarctic Peninsula and some sub-Antarctic islands.

3.10.2.1

Arctic Coastal Geomorphology

The central position of the Arctic Ocean is the dominant feature of the Arctic region (Figure 1). In contrast to Antarctica, the major ice sheets and ice caps in the Arctic (the Greenland Ice Sheet and ice caps in the Canadian, Norwegian, and Russian Arctic) are located on peripheral islands and do not extend to the pole. Glaciers reach the sea in the eastern Canadian Arctic (Baffin, Bylot, Devon, Ellesmere, and Axel Heiberg islands), in Greenland, Svalbard, northernmost Norway (fed by avalanch­ ing from above), the Russian Arctic, and in southeastern Alaska. Rapidly declining ice shelves also remain in northern Canada and Russia (see also Chapter 3.07). General descriptions of Arctic coastal geology and morphol­ ogy are provided by Hartwell (1973), Wiseman et al. (1973), Walker (1985), Jorgenson and Brown (2005), and Walker and McGraw (2010) for Alaska; by Bird (1967, 1985), Taylor and McCann (1983), Shaw et al. (1998), and Pollard (2010) for Arctic Canada; by Nielsen (1985) for Greenland; and by Zenkovich (1985), Drozdov et al. (2005), Selivanov (2003), and Ogorodov (2003) for the Russian Arctic. More recently, as a product of the Arctic Coastal Dynamics Project (Rachold et al., 2005), a circumpolar coastal classification has been completed

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in GIS format (restricted to coasts directly fronting the Arctic Ocean; GIS, geographic information system), enabling a synth­ esis of coastal geology and geomorphology, including ice content and estimates of sediment and carbon delivery to the Arctic basin from coastal erosion (Rachold et al., 2003a, 2003b; Lantuit et al., 2008b, 2009, 2010, 2011). The circumpolar Arctic coast can be broadly subdivided into regions that are rock dominated and those that are underlain primarily by ice-bonded but otherwise unlithified sediments (Figure 8). Rock-dominated coasts occur across a wide spec­ trum of relief – from mountains to coastal plains – and lithologies – from highly resistant, crystalline, shield rocks in parts of Canada and Scandinavia to a broad range of volcanic and sedimentary lithologies elsewhere. Major mountain belts with associated fjord systems extend north to south along the eastern margin of the Canadian Arctic (Ellesmere Island to Labrador), in eastern Greenland and Svalbard, along the Norwegian coast, and in the northward extension of the Ural Mountains through Novaya Zemlya. Rock-bound coasts with lower relief occur around Hudson Bay, through the Canadian Arctic Archipelago, on the Kola Peninsula and the skerry coast of the western White Sea in northwest Russia, on the Taymyr Peninsula and Severnaya Zemlya, Franz Josef Land, the New Siberian Islands, along mountain spurs intersecting the coast in Chukotka, on the Seward and Lisburne Peninsulas in western Alaska, and in Iceland and the Faeroes (otherwise not treated here). Coastal morphology ranges from rock cliffs in fjords and

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Figure 8 Arctic coastal geomorphology: (a) Terminus of Sermilik Glacier, Bylot Island, Nunavut, with proglacial outwash sediment delivery to Eclipse Sound and coastal erosion of moraine deposits in the left foreground; (b) Gull Cliffs, with talus rampart and basal gravel beach, southeast Lowther Island, Viscount Melville Sound, Nunavut; (c) gravel nearshore shoals, spit, and beaches with emerged relict beaches, west side of Griffith Island near Resolute, Nunavut; and (d) gravel beach and eroding bluff in ice-wedge polygon terrain, Barrow, Alaska. (a, b, c) Photo: DL Forbes (2009). (d) Courtesy: R.B.Taylor.

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along open coasts to skerries in the western White Sea and western Taymyr Peninsula, to talus ramps in parts of the Canadian Arctic (e.g., Figure 8(b)) and Franz Josef Land. Many of these coasts were glaciated during the LGM (Clark et al., 2009) and have substantial deposits of unlithified glaci­ genic deposits locally (cf. 00309) or, on emergent coasts, a veneer of marine sediments and extensive sequences of emerged beaches (e.g., Bird, 1954; Blake, 1970; Andrews, 1970, 1989; Forman et al., 1987; Bednarski, 1988; Dyke and Dredge, 1989; Fletcher et al., 1993; Brückner et al., 2002; Møller et al., 2002; Kaplin and Selivanov, 2005; St­ Hilaire-Gravel et al., 2010). In some regions, however, emer­ gent marine deposits predate the LGM (Brigham-Grette and Hopkins, 1995; Gualtieri et al., 2003). Regions of high relief with extensive glaciation including Baffin Island, eastern Greenland, and Svalbard have a complex coastal mosaic of fjord systems with shear cliff walls and rock slopes with thin or discontinuous covers of coarse colluvium, tidewater glaciers, fjord-head deltas, outer coast glacial fore­ lands, and small bays with covehead beaches and barriers, flanked by narrow, discontinuous gravel beaches, sometimes with boulder barricades (Figure 9). Most have experienced postglacial uplift, leaving sequences of emerged deltas in degla­ ciated fjord-head valleys (e.g., Briner et al., 2006), emerged beaches in limited areas with sufficient sediment and wave energy, and mantles of marine sediment in other areas

(e.g., Nixon, 1988; Evans and Rea, 2005). Large sedimentary plains or forelands are present along the outer coast of eastern Baffin Island. In this area, earlier uplift has given way to slow submergence, and coastal bluffs are cut into the outer front of the Clyde foreland along 30 km of the Baffin Bay coast (Figure 9(c)), exposing a complex interglacial–glacial– interglacial sequence of glacial, glacifluvial, and marine sedi­ ment with interbedded organic deposits (Miller et al., 1977). Sediment sourced from the cliffs has been transported south under northeasterly waves in Baffin Bay to accumulate in a wide beach system against a bedrock headland. Transgressive barriers in more open proglacial or paraglacial settings are present on the submerging coasts of northeast Bylot Island (see also Chapter 3.07) and on parts of Svalbard. Etzelmüller et al. (2003) reported on detailed coastal classifica­ tion and mapping for the entire Svalbard archipelago. Héquette and Ruz (1986, 1990) and Héquette (1992) conducted studies of transgressive gravel barriers migrating slowly landward under rising sea levels on northwestern Spitsbergen. Elsewhere on southern Spitsbergen, Ziaja et al. (2007, 2009) have described the development and rapid change in gravel beaches and barriers sourced from moraines and talus slopes in an area of rapid glacial retreat. An extensive Arctic coastal plain (Figure 1) extends from the Laptev Sea in northern Russia eastward along the Siberian coast to the Chukchi Sea coast of northwest Alaska, the North Slope

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Figure 9 Baffin Island coast. (a) Steep rock walls and colluvial ramps, Tingin Fiord, east Baffin Island, Nunavut, with plume of sediment from small ice cap on plateau. (b) Coarse clastic beach on the shore of Patricia Bay, Clyde Inlet, east Baffin Island, Nunavut. (c) Cliff cut in interbedded glacial and outwash sediments of the Clyde foreland. Note boulders, ice and snow at base of beach and underlying sediment in foreground, and narrow portion of wave-worked beach, with drift ice remaining along the shore, north of Cape Christian, east Baffin Island, Nunavut. (d) River-mouth spit with fine-medium quartz sand and garnet placer units, Igloo Bay, Clyde Inlet, Baffin Island, Nunavut. Photo source: DLF, 2008, 2008, 2007, 2007

Polar Coasts

of Alaska and Yukon, and the Mackenzie Delta region includ­ ing the Tuktoyaktuk Peninsula to the east (Zenkovich, 1985; Hill et al., 1995). The coastal plain extends north along the western flank of the Canadian Arctic Archipelago (western Banks and Prince Patrick Islands) and merges with low-lying terrain on poorly lithified formations of the Sverdrup Basin on Borden, Mackenzie King, Lougheed, northern Melville, and other islands (Hodgson, 1989). Other lowland coasts in north­ ern Russia occur west of the Taymyr Peninsula, on islands in the Kara Sea and the adjacent coast in the vicinity of the Ob and Baydaratskaya Bay, and further west in the Pechora Sea, Kolguev Island, and the Mezen Gulf region of the Barents Sea (Zenkovich, 1985). The latter has a spring tidal range up to 10 m, but many parts of the Arctic Coastal Plain have very modest tidal range (as little as 0.5 m in the Beaufort Sea, where the astronomical tide is greatly exceeded by meteorolo­ gical surge effects). The entire region is characterized by continuous permafrost (ground temperatures <0 °C in places extending to 700 m or more below ground level), very limited exposures of lithified rock, and extensively ice-bonded sedi­ ments with local excess ice (Figure 4). Some regions have extensive sediment cover with ground ice contents up to 80% or more (e.g., the so-called ‘ice complex’ coasts). Where exposed at the surface through coastal or other erosional pro­ cesses, deposits with excess ice are highly unstable and fail through a variety of distinctive mechanisms such as

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retrogressive thaw flow (RTF) failure and thermal niche under­ cutting and collapse (Section 3.10.3.4). Much of the Arctic coastal plain is transgressive (Figure 6), with former land areas, associated drainage networks, and permafrost now submerged on the continental shelf (Mackay, 1972; Hunter et al., 1976; Sellman and Hopkins, 1983; Dallimore and Taylor, 1994; Hinz et al., 1998; Kleiber and Niessen, 1999; Rachold et al., 2007). Some regions of the coastal plain in Canada, Alaska, and Siberia have very high concentrations of lakes originating as glacial kettles, thermo­ karst basins, or through other mechanisms (Carson and Hussey, 1962; Sellmann et al., 1975; Harry and French, 1983; Grosswald et al., 1999; Hinkel et al., 2005; Bryan et al., 2006; Jorgenson and Shur, 2007). Coastal morphology in these regions is highly irregular because of rapid erosion rates and breaching of lake basins (Zenkovich, 1985; Ruz et al., 1992; Hill et al., 1995). This is particularly evident in the Mackenzie Delta and Tuktoyaktuk Peninsula region of northwestern Canada (Figure 10) and in the Kara Sea and other places along the Russian Arctic coast. Island remnants of ice-rich coastal plain deposits are rapidly removed by a combination of thermal and mechanical processes (Figure 10(c)) and, in some cases, have disappeared, leaving shoals on the shallow continental shelf (Zenkovich, 1985; Overduin et al., 2007). Breaching and coalescence of lake basins combined with spit and barrier beach development produce a highly intricate

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Figure 10 Arctic coastal plain: (a) marine transgression across thermokarst terrain with lakes, partially drained lakes with pingos, thin transgressive barrier beach, and irregular nearshore bar near Tuktoyaktuk, NWT; (b) drowned ice-wedge polygon tundra, west coast of Banks Island; (c) rapid retreat of cliffs with massive ice, Pullen Island (see Figure 13 for location); and (d) Kay Point spit, Yukon coast, showing extensive washover deposits and large proportion of driftwood originating in the Mackenzie River. (a, b) Photo: DL Forbes (2002). (c) Photo: DL Forbes (1975). (d) Photo: DL Forbes (1974).

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shoreline in the southeastern Beaufort Sea. In most cases, the barriers are low and readily overwashed (Figure 10(d)), migrat­ ing landward, but in locations with sufficient sediment supply, spit extension or beach–ridge progradation can occur (Forbes, 1980, 1997; Hill, 1990; Forbes et al., 2004). An exception to this pattern occurs in the southwest East Siberian Sea (east of the Kolyma River) where the onshore topography and offshore bathymetry slope so gently that positive storm surges flood up to 30 km inland and negative surges lay bare large areas of the shallow seabed (Zenkovich, 1985). Large-scale spits and forelands are rare in the Canadian Arctic, although a large flying spit has developed at Cape Kellett at the southwest corner of Banks Island, and extensive spits and barriers fringe the transgressive west coast further north, fed by erosion of ice-rich, unlithified Quaternary and earlier deposits (Figures 3(b) and 11(a) and 11(b)). An exten­ sive system of low sand and gravel spits and barriers, locally sourced from eroding permafrost bluffs, is present along the entire Tuktoyaktuk Peninsula, on Pleistocene island remnants off the Mackenzie Delta, and along the Yukon coast (Figures 10(a), and 10(d)). Where gravel is present, these take the form of mixed sand–gravel barriers with low storm crests and extensive washover sheets or lobes (Forbes, 1997). East of the Mackenzie Delta, where sand is more abundant, the spits and barriers are very low, subject to frequent washover

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and wind deflation, and are migrating landward at rates as high as 3–4 m a−1 (Héquette and Ruz, 1991; Ruz et al., 1992), although the mean rate for the entire coast is somewhat slower and time variable (cf. Solomon, 2005). A large foreland at Cape Charles Yorke on the northern tip of Baffin Island (Lancaster Sound) and smaller forelands in Navy Board Inlet nearby show seaward-rising beach crests, indicative of slow relative sea-level rise (Figures 11(c) and 11(d)). Much larger coastal beach– ridge complexes are well developed in northern Alaska, particularly along the Chukchi Sea coast west from Cape Barrow (Mason and Jordan, 1993). An extensive barrier system extends almost 70 km to the northeast and 50 km to the south of Point Lay. Short (1979a, 1979b) reported on the extensive coastal barrier systems fronting 55% of the Chukchi and Beaufort coasts in Alaska and Yukon. Throughout the coastal plain region, small and large barriers enclose shallow lagoons. There is a considerable literature on lagoon systems of the Alaska coast (e.g., Craig et al., 1984; Matthews and Stringer, 1984; Naidu et al., 1984). Mason et al. (1997) and Jordan and Mason (1999) reported on detailed studies of the large Cape Espenberg spit and Shishmaref barrier to the south. Extensive barriers enclosing large lagoons are present along the Siberian Chukchi coast, with large opposing spits 18 and 32 km long at the mouth of Kolyuchinskaya Bay (Zenkovich, 1985). One area of very extensive barrier development is

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Figure 11 Arctic spits and forelands: (a) spit extending south along west coast of Banks Island north of Cape Kellett – note recurved ridges on spit platform, with ice scour evident in foreground; (b) elbow of L-shaped flying spit at Cape Kellett, southwest point of Banks Island, 6.5 km from proximal connection in distance and 2.5 km from tip of spit to left out of view; (c) small forelands in Navy Board Inlet (NBI in Figure 1), Baffin Island, looking north – prograded ridges in foreground decrease in age and rise seaward toward camera, attesting to slowly rising relative sea level in this area; and (d) beach truncating seaward-rising prograded gravel beach ridges at Cape Charles Yorke, northernmost point of Baffin Island (CY in Figure 1). Photo source: DLF, 2002, 2002, 2009, 2009.

Polar Coasts

along the southern shore of the Pechora Sea (southeastern Barents Sea), in the partial lee of Kolguev Island, where north­ eastward longshore transport over a distance of about 200 km terminates in a 50-km spit (Russkii Zavarot) that extends beyond as a subaqueous shoal with emerging islands (Gulyaevskie Koshki Islands) across the mouth of the Pechora River Estuary (Zenkovich, 1985; Ogorodov, 2003, 2005a). Kolguev Island shows an erosional northwestern face to the open Barents Sea, with sediment transported around both sides of the island to a complex set of barriers, spits, and lagoons at the east and southwest corners of the island (Figure 12). Another noteworthy coastal foreland struc­ ture is at Intsy, on the east side of the White Sea throat, where sandy beach ridges have been reworked into dunes (Zenkovich, 1985). Large rivers sourced far to the south flow northward to deltas and estuaries in the Arctic: these include the Mackenzie, Churchill, and Nelson rivers in Canada (the latter two entering Hudson Bay south of the Arctic Circle) and the Ob’, Yenisey, Lena, Indigirka, and Kolyma rivers in Russia. The White Sea is the receiving basin for a large watershed in northwestern Russia, including the Dvina River entering at Arkhangelsk. The Yukon, the largest river in Alaska, has headwaters in the St. Elias Mountains of northern British Columbia and Yukon, crosses the Arctic Circle for a short distance near Fort Yukon, and flows 48 E

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west to enter the Bering Sea through a large delta at about 62° N latitude. The largest Arctic deltas are those of the Lena (~73° N) and the Mackenzie (~69° N) (Figures 13 and 14(a) and 14(b)). Other notable Arctic deltas include the Colville in northern Alaska (a location of extensive research; e.g., Walker, 1969, 1974, 1976, 1998; Walker and Hudson, 2003), the Kolyma, Alazeya, Indigirka, Yana, and Omoloy in Siberia, and the Pechora on the mainland Russian coast southwest of Novaya Zemlya. Limited work has been undertaken on smaller Arctic deltas in Canada (Figure 14) (e.g., Forbes et al., 1994) and the Coppermine (western Nunavut). A number of rivers draining the North Slope in Alaska and Yukon terminate in extensive fans with discontinuous small barriers and shallow lagoons, with local scarping along their outer margins. Many of the Russian rivers enter the sea through large estuaries, particularly the Ob Estuary (Obskaya Guba), which extends through 6° of latitude (over 600 km) (Whitehouse et al., 2007). The estuaries of the Churchill and Nelson rivers in southwest Hudson Bay, where relative sea level is falling at a rate of about 10 mm a−1, demonstrate that estuarine morphology is not intrinsically a function of relative sea-level rise. One consequence of the large northward-flowing rivers is a significant delivery to the Arctic Ocean of logs from forested areas in the headwaters. These form significant accumulations 50 E

0.2 m yr −1

Pechora Sea

69 N

69 N

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20 km

2 m yr −1

Net longshore transport Alluvial and littoral Lacustrine (thermokarst) Glacial and glacial-marine

48 E

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Figure 12 Kolguev Island, Pechora Sea, showing slow erosion of high bluffs in Pleistocene glacigenic sediments at north end of the island, feeding longshore transport along both flanks to large spit complexes at the south and east ends of the transport corridors. The south end of the island has a wide, low, lake-studded plain, the somewhat protected margin of which is eroding approximately 10 times faster than the north end of the island. Extensive tidal flats are contained behind the southern spits and barrier islands (see Figure 1 for location). Data sources: Coastline derived from overlay of 2010 imagery on Google Earth®; interpretation and erosion rates from Nikiforov, et al., (2003). and Ogorodov, (2005a).

256

Polar Coasts

Figure 13 Landsat-7 mosaic of Mackenzie Delta and vicinity, showing Holocene deltaic plain infilling a glacial trough and spilling over Pleistocene uplands on Richards Island. Remnant islands of ice-rich Pleistocene deposits north of the delta are eroding rapidly. The lake-studded coastal plain of Richards Island and the Tuktoyaktuk Peninsula can be seen clearly, as well as the intricate coastline formed by the landward retreat of the shoreline with lake breaching and coalescence (cf. Ruz et al., 1992; Hill et al., 1995).

in many places, particularly in the regions of major rivers such as the Lena and Mackenzie, and far-traveled driftwood is found on modern and emerged beaches throughout the Arctic (Häggblom, 1982; Dyke et al., 1997). These rivers with south­ ern catchments also begin flowing in spring, often well before ice breakup at the coast, so that sediment-laden freshwater floods out over the sea ice to drain through cracks and sink­ holes, causing distinctive strudel scours pits in the seabed (Reimnitz and Bruder, 1972; Reimnitz et al., 1974; Solomon et al., 2008).

3.10.2.2

Antarctic Coastal Geomorphology

In contrast to the Arctic, the South Polar region is dominated by the large Antarctic Ice Sheet (AIS) (Figure 2). This can be

subdivided into the East Antarctic Ice Sheet (EAIS), an ice dome that rises to a maximum elevation of 4200 m above sea level, and the lower and smaller West Antarctic Ice Sheet (WAIS). The ice sheets, glaciers, and ice shelves together cover 13.5 million km2 with a volume of approximately 30 million km3 (Drewry, 1991). The EAIS is thought to have reached almost its present size about 14 million years ago (Ma) (Sugden, 1992), with the WAIS forming after 10 Ma, although the first tidewater glaciers were present on the continent as early as 42.5 Ma in East Antarctica and 49.4 Ma in King George Island, West Antarctica (Hansom and Gordon, 1998). Today, about 95% of the Antarctic coast has ice at tidewater (Figure 5), occurring as ice shelves, grounded ice margins, or tidewater glaciers (Drewry et al., 1982). Approximately 38% takes the form of ice walls at the seaward limits of the ice sheet

Polar Coasts

(a)

(b)

(c)

(d)

257

Figure 14 Arctic deltas: (a) large bend in Middle Channel, central Mackenzie Delta looking southwest, with Richardson Mountains in the distance; (b) subtle levee and bank erosion along outer delta front associated with anomalous low water levels (negative surge), Mackenzie Delta; (c) spring flood on Babbage Delta, Yukon coast, with floating ice confined to deep channels and bottomfast ice submerged, looking seaward to the west; and (d) Mahogany Point fan delta, north coast of Banks Island in M’Clure Strait. Photo source: DLF, 2007, 2007, 1974, 2006

(Swithinbank, 1988). Tidewater outlet glaciers account for 13% of the Antarctic coast and also occur on most sub-Antarctic islands (Figure 3(a)) (Drewry et al., 1982). The same authors found that ice shelves occupied 44% of the Antarctic coast (Figures 15(a)), an area of 1.542 � 106 km2 or 11% of the total ice cover of Antarctica. Permafrost is widespread in Antarctica (Figure 5), although the known distribution is pat­ chy (Bockheim, 1995). The circular bulk of the EAIS sits above a rocky continent which lies mostly above sea level. The EAIS is pierced in only a few places such as the 3630-m-high nunataks of the Sor Rondane Mountains of the Queen Maud Land coast. By contrast, West Antarctica is a 1200-km-long bedrock archipe­ lago with much of the WAIS between the Ross and Weddell seas resting on rock that is typically > 800 m below sea level (Drewry, 1983). In the Antarctic Peninsula, spectacular coastal mountains tower above a landscape of tidewater glaciers flanked by steep fjord walls. The boundary separating West Antarctica from East Antarctica is dramatically marked by the 3500-km range of the Transantarctic Mountains. These steeply flank the coast from Cape Adare in Victoria Land to the south­ ern limit of the Ross Ice Shelf and meet the coast again at the Pensacola Mountains at the Filchner Ice Shelf in the Weddell Sea (Hansom and Gordon, 1998). On all sides, the continent is bordered by a predominantly narrow and unusually deep con­ tinental shelf with a mean width of 200 km and a mean depth of 500 m (Anderson, 1991). The widest parts of the shelf

underlie the Rönne–Filchner and Ross ice shelves. Much of the inner part of the shelf slopes toward the continent rather than offshore and is probably the combined result of isostatic depression and glacial erosion. The ice-free parts of the East Antarctic coast mainly rise inland as shallow and glacially scoured rocky ramps, but the rock gradient is generally much steeper and often cliffed where mountains border the coast such as in parts of the Antarctic Peninsula, the Trans-Antarctic Mountains in Victoria Land, and in scattered areas in the Pacific and Atlantic sectors. Only 5% of the Antarctic coast is ice free, although there are significant regional variations with 28% of the coast in Victoria Land free of ice, rising to 85% in South Georgia, both areas where much of the coast is steep, rocky, and fjord like (Figures 3(a), 15(c), and 16(a))) (Hansom and Kirk, 1989). The rate of sediment delivery to the Antarctic coast is extremely low in comparison to glaciated coasts elsewhere. Further, because there is little or no meltwater activity, the Antarctic coast lacks the sediment delivery systems that are characteristic of Arctic coasts. Much of the coast is ice-free for only short intervals of time in the summer season and some areas may see no open water for years where sea ice remains landfast throughout the melt sea­ son. Antarctic and sub-Antarctic coasts are mainly microtidal, with spring tidal ranges usually well short of 2 m and in many places much less than 1 m. There is little information available about the extent and nature of the rocky coast of much of Eastern Antarctica, except

258

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(a)

(b)

(c)

(d)

Figure 15 Antarctic and sub-Antarctic coasts: (a) RRS Bransfield moored at Brunt Ice Shelf cliff and unloading supplies to the UK base at Halley Bay; (b) cliffs at Cape Adare, northern Victoria Land; (c) St. Andrews Bay, South Georgia showing debris-charged glacier snout, gravel barrier, and field camp with king penguins in foreground; and (d) 1-km-wide horizontal shore platform at sea level backed by emerged shore platforms inland, South Shetland Islands. Photo sources: (a) courtesy A. Alsop, 1990; (b) courtesy M. Usher; (c) JDH, 1977; (d) courtesy D.E. Sugden, 1967

for some areas close to scientific bases. High relief in Victoria Land has produced cliffs up to 2000 m high that border the Ross Sea (Gregory et al., 1984). In this region, 22% of the coast is rock cliff, leaving 6% as noncliffed ice-free coast, of which beaches comprise 3% (Hansom and Gordon, 1998). In many locations on the mainland and on the sub-Antarctic islands, ice from permanent ice caps and glaciers spill down steep rocky cliffs which plunge below sea level (Figure 16(a)). The short duration or the absence of wave action enables the develop­ ment of narrow, ice-cored ridges at the base of talus slopes below some cliffs in both Victoria Land and along the Antarctic Peninsula and its offshore islands. Where the coast on the Antarctic Peninsula and its offshore islands are not backed by cliffs, low-relief rock shores occur that are character­ ized in places by wide, gently sloping shore platforms (Figure 15(d)). These have developed primarily through a combination of freeze–thaw activity and grounding ice (Hansom, 1983a). Where glacigenic boulders are present in the intertidal zone, grounding ice has compacted them into extensive pavements of polished and striated surfaces (Hansom, 1983b). Recent volcanic activity has also shaped the coast. At Penguin, Bridgeman, and Deception in the South Shetland Islands, erosion of the friable rocks of relatively active volcanoes has produced cliffs and small beaches. The inun­ dated inner crater of Deception Island is bordered by gravel beaches, in sharp contrast to the cliffs of the outer coast. The

South Sandwich Islands consist of a 400-km-long volcanic island arc rising from an ocean trench that is 8428 m deep, and the coastline is characterized by cliffs, reefs, and skerries with infrequent small bouldery pocket beaches (Hansom, 2005a, 2010). Beaches occupy a very small part of the Antarctic coast. Most are unrecorded with a limited but unknown total extent. In Victoria Land, they form 3% of the coast, with a prime example being the gravel foreland at Ridley Beach, Cape Adare (CA in Figure 5; Figure 16(b)). Small beaches are more plentiful along the Antarctic Peninsula, and especially in the sub-Antarctic islands such as South Georgia, where plentiful sediment and open-water conditions favor the development of larger bea­ ches. Beaches play an important ecological role, providing haul-out sites for seals and habitats for penguin rookeries (Figure 16(c)) (Hansom and Kirk, 1989). Where there are large concentrations of penguins, pebbles may be missing from swales (having been collected for nests) and beach–ridge gravels may be cemented by guano (Kirk, 2010). Much of the early work on ice-foot development took place in the Antarctic, where the ice foot is a prominent feature at most beaches much of the year (Nichols, 1961). As in the Arctic, other processes at work include ice push (possibly lead­ ing to some beach nourishment from the nearshore) and intermittent wave action (Nichols, 1961, 1968; Butler, 1999; Hall and Denton, 2000). The Ross Sea coast of Victoria Land is

Polar Coasts

(a)

(b)

(c)

(d)

259

Figure 16 Antarctic and sub-Antarctic coasts: (a) plateau and glacier ice spilling over steep rock cliffs into the sea choked with floating ice, south coast of South Georgia; (b) Ridley Beach, a cuspate foreland on the southwest side of Cape Adare, northern Victoria Land, Antarctica, looking south; (c) gravel barrier beach fed from proglacial outwash deposits fronting a debris-laden retreating glacier, Fortuna Bay, north coast of South Georgia; and (d) the glacial moraine of Zenker Ridge, flanked by gravel and boulder beaches, arcs across the open waters of Moraine Fjord, north coast of South Georgia. Photo sources: (a) and (c) JDH, 1976; (b) courtesy S. Emslie, 2005; (d) JDH, 2003.

exposed to energetic waves under open-water conditions, and the cobble–boulder storm beaches there have crest elevations about 4 m above sea level (Kirk, 1991). Higher beach deposits at many sites, including Cape Ross, are emerged features of Holocene or earlier age and represent the effects of glacio-isostatic uplift (Gardner et al., 2006). The Ridley Beach foreland at Cape Adare (Figure 16(b)) is about 2 km across and consists of prograded gravel beach ridges with crest elevations of 4–6 m (Mabin (1982), cited by Harrowfield (2006) and Kirk (2010)) attesting to long-term longshore transport by local waves from the south with reworking of the northern (exposed) face by Southern Ocean swell. The beach sediment consists of basalt sand and pebble-sized gravel, much of which is cemen­ ted by guano from the large numbers of Adélie penguins at the site (Harrowfield, 2006). Small sand beaches can be found in other protected north-facing sites (Hall and Denton, 2000), but are rare on the mainland. More extensive sand beaches are present on the sub-Antarctic islands, where the subaerial and glacial environment delivers large volumes of sand and gravel to the coasts of South Georgia (Figure 16(c) and 16(d)) (Gordon and Hansom, 1986), Heard Island (Kiernan and McConnell, 1999), and the nearby Îles Kerguelen (Hansom and Gordon, 1998). Unlike the Arctic coast, where glacial tills and moraine are found in association with extensive deposits of fluviatile sands

and gravels, a very different situation occurs on the Antarctic continent. Glaciers at the coast mainly lose mass by calving and basal melting, because of which glacigenic material is sparse. Minor melt streams do emanate from the surfaces of some glaciers in summer, but they are small and rarely produce substantial amounts of sediment. The largest streams in Antarctica occur in ice-free oases of East Antarctica, in the Vestfold Hills (the Talg and Tierney streams) (Qingsong and Peterson, 1984) and in Wright Valley, Victoria Land (the Alph and Onyx streams), all of which can have flow rates in excess of 2 � 106 m3 yr−1 and are fed entirely by glacier melt in the 8 weeks of summer. There is evidence of past meltwater erosion, such as deeply eroded meltwater channels in the Antarctic Peninsula (Clapperton and Sugden, 1982) and the meltwater channels that lace the ice-free plateaus of the South Shetland Islands (John, 1972), but these are uncommon on a continen­ tal scale. Most of the present meltwater activity is related to snowmelt, particularly in areas such as the South Shetland Islands where channel networks and depositional fans occur (Birnie and Gordon, 1980). As a result, the delivery of fluvial sediment to the continental coast is negligible. By contrast, in the warmer climate of South Georgia, Heard Island and Îles Kerguelen, glacier meltwater has a much greater influence. For example, on South Georgia meltwater has constructed the lar­ gest glacifluvial plains to be found anywhere in the Antarctic.

260

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3.10.3.2

3.10.3 Polar Shore Processes 3.10.3.1 Polar Glacial Processes: Ice Sheets, Tidewater Glaciers, and Ice Shelves A review of glacial coasts is provided by Forbes (see Chapter 3.07). Surface meltwater is much more limited in the Antarctic than along most Arctic glacial margins, resulting in lower production of glacigenic sediment. In addition, relatively little of the glacial sediment production is captured in the Antarctic coastal system, most being exported in plumes of suspended sediment to marine sinks beyond the reach of shore processes. Glacial coasts (tidewater glaciers and ice shelves) in both polar regions show dramatic retreat in recent years, particularly on northern Ellesmere Island (Canada), Greenland, and on the Antarctic Peninsula (Cook et al., 2005; Mueller et al., 2008; Cook and Vaughan, 2009). The importance of Antarctic ice shelves in stabilizing outlet glaciers from the WAIS and impli­ cations for global sea level have focused attention on this issue, including ongoing efforts to refine the coastline using satellite altimetry data (Hamilton and Spikes, 2004) and synthetic aperture radar (SAR) imagery (Liu and Jezek, 2004) and to build robust digital elevation models (Jezek et al., 1999). Recent observations show thinning over the WAIS in response to acceleration of outlet glaciers, in particular the Pine Island ice stream (Payne et al., 2004; Shepherd et al., 2004; Vaughan, 2005). Similarly, in Greenland, acceleration of outlet glaciers has increased dynamic thinning of the Greenland Ice Sheet (Pritchard et al., 2009). New estimates show that mass loss from glaciers and ice caps contributes about 1.2 mm yr−1 to global sea level, while the contributions from Greenland and Antarctica are nearly equal and amount to about 0.7 mm yr−1 (Velicogna, 2009).

55° S

(a)

Polar Marine Processes: Sea Ice and Shore Ice

The dramatic seasonal variation in the extent of sea ice that forms a lid on the surface of the ocean is a defining character­ istic of polar coasts (Figure 17). In the Northern Hemisphere, ice occurs in higher latitudes in Hudson Bay, the Canadian Arctic Archipelago, the Labrador coast, East Greenland and Northern Iceland, in the Baltic including the Gulf of Bothnia and the Gulf of Finland, in the White Sea, and throughout the circumpolar Arctic Ocean, contributing to distinctive shore processes and hazards. Winter pack ice also extends to mid-latitudes in eastern Asia and Alaska (in the Sea of Okhotsk, the northeast coast of Hokkaido, and the Bering Sea; e.g., Akagawa, 1964; Matsuoka et al., 2002; Otsuka et al., 2005; Overland and Wang, 2007), and in eastern North America (in the Bay of Fundy, the Gulf of St. Lawrence, and eastern Newfoundland, as well as in the Great Lakes; e.g., Owens, 1976; Gordon and Desplanque, 1981; Grass, 1984; Dionne, 1984, 1988; Kempema and Reimnitz, 1991; Barnes et al., 1994; Kempema et al., 2001). In the Southern Hemisphere, sea ice is confined to the margins of the Antarctic continent and nearby islands, including the Antarctic Peninsula and the South Orkney and South Shetland Islands (Figure 17). South Georgia is only occasion­ ally affected and the South Sandwich Islands remain largely free of sea ice. The Antarctic summer minimum in February can be as low as 3.5 � 106 km2 and is largely confined to the coast, but the winter maximum in September covers 19 � 106 km2 and extends up to 2200 km from the coast, effectively doubling the area of the Antarctic region that is covered with ice (Figure 18) (Zwally, et al. 1983; Gloerson et al., 1992). The ice season depends on the latitude and can range from as short as a few days to weeks in areas affected by late-winter export

55° S

(b)

Weddell Sea

Weddell Sea

South America

South

America

South Pole

Bellingshausen Sea

Amundsen

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55° S

Amundsen Sea

Ross Sea

55° S

Distribution of sea ice on 26th August 1974

Mean distribution of sea ice in September

Distribution of sea ice on 8th January 1975

Mean distribution of sea ice in February

Figure 17 Seasonal variation in south polar sea-ice distribution and extent from satellite passive microwave observations: (a) 1974–75; (b) mean distribution for winter and summer averaged over 1978–87. From Hansom, J.D., Gordon, J.E., 1998. Antarctic Environments and Resources: A Geographical Perspective. Addison Wesley Longman, Harlow, 402 pp.

Polar Coasts

and coastal drift of pack ice, to >3 months in the southern Gulf of St. Lawrence and >11 months at Alert, at 82° N on the Arctic Ocean (Taylor and McCann, 1983). A similar pattern exists in the Southern Hemisphere. Much attention has been focused on reductions in the thickness and extent of Arctic Ocean sea ice over the past few years. Stroeve et al. (2007) reported that the extent of Arctic ice in September (end of the melt season) declined by 7.8% per decade from 1953 to 2006, and the loss accelerated to 9.1% per decade for the period of satellite observations (1979–2006). They also observed declines (but slower) in March ice extent (−1.8% and −2.9%, respectively) and sug­ gested that a substantial part of these trends is attributable to climate change (Figure 18). The remainder of the variance may be associated with temporal variability related to changes in the Arctic Oscillation, among other factors. A record low value of annual minimum ice cover was recorded in September 2007 when the total extent and area dropped to 4.1 � 106 and 3.6 � 106 km2, respectively, 24% and 27% lower than the previous record low values of September 2005 (Comiso et al., 2008). Dramatic loss of multiyear ice in the Arctic Ocean, particularly older and thicker multiyear ice, and an overall thinning of the Arctic Ocean ice cover (Maslanik et al., 2007; Kwok et al., 2009) have caused concern about a possible tipping point, leading to even greater ice loss. More recent analysis suggests that this is unlikely so long as a sub­ stantial ice cover remains in place for a large part of the year (Eisenman and Wettlaufer, 2009), although it has also been suggested that the multiyear ice extent as determined from satellite imagery may be misleading and that much of what appears to be thick competent multiyear or thick first year floes may have very low strength (Barber et al., 2009). Although large areas of the Arctic sea ice may be multi­ year ice such as occurs within the large Beaufort Gyre, most Antarctic sea ice is annual with multiyear ice accumulating only where gyres exist in the Weddell Sea, the Ross Sea,

261

and, to a lesser extent, the Bellingshausen Sea. Gloerson et al. (1992) found a 5% interannual variability in winter sea ice extent. Using scanning multichannel microwave radiometer data, Gloerson and Campbell (1988) found no significant change in the amount of Antarctic sea ice cover between 1978 and 1987, the same time interval in which the Arctic sea-ice cover declined significantly. Curran et al. (2003) deduced a 20% decline in sea-ice extent since the 1950s, based on indirect evidence from ice cores. Recent work by Stroeve et al. (2007) found that overall changes in Antarctic sea-ice cover have shown minor trends that are not statistically significant (Figure 18). Some regions of the Antarctic show stronger declines in ice extent but the trends are variable and recent satellite data suggest a slight positive trend overall (Cavalieri et al., 2003; Cavalieri and Parkinson, 2008). Floating ice inhibits the formation of surface gravity waves (Masson and LeBlond, 1989) and incoming ocean swell or storm waves are attenuated by pack ice, particularly at higher concentrations (Wadhams, 1973; Squire and Moore, 1980; Squire et al., 1995; Squire, 2007; Broström and Christensen, 2008). The thickness, concentration, and rigidity of the ice are critical factors affecting wave energy and waves may propagate some distance through grease ice, slush ice, and pancake ice, despite damping (Martin and Kauffman, 1981; Broström and Christensen, 2008). Storm surge development is inhibited but not precluded by ice cover and winter overflow can occur through tidal cracks, sometimes with explosive force (Reimnitz and Maurer, 1979a). Taylor (1981) provided a detailed account of storm waves interacting with ice on a beach along the northeast coast of Bylot Island, Nunavut, with a storm duration of about 2 days, moderate winds up to 50 km h−1, and a 280-km fetch across open water in Baffin Bay. Wave attenuation varied dramatically through the storm, as first year ice was broken up and large blocks of multiyear or bergy ice accumulated along the

Sea-ice index (extent in 106 km2)

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Figure 18 Sea-ice index (late summer total extent) in 106 km , 1979–2010, showing dramatic decline in Arctic ice extent and minimal (though recently more variable) trend for the Antarctic. Data from Fetterer, F., Knowles, K., Meier, W., Savoie, M., 2002 (updated 2009). Sea Ice Index. National Snow and Ice Data Center, Boulder, Colorado. Digital media. http://nsidc.org/data/seaice_index/archives/index.html (accessed February 2011).

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(a)

(b)

(c)

(d)

Figure 19 Ice in the shore zone: (a) storm with large ice blocks wallowing in surf, Bylot Island, Nunavut; (b) ice foot (flat terrace at left) and tidal crack with ice pile-up in a macrotidal setting (spring range 12 m) at low tide in mid-winter, Iqaluit, Nunavut; (c) incipient ice foot with grease ice, beginning of freeze-up, Hall Beach, Nunavut; and (d) unloading supplies onto an early summer ice foot in a sheltered setting, Antarctic Peninsula. Photo sources: (a) courtesy R.B. Taylor, 1982; (b-c) DLF, 2008; (d) JDH, 1975

beachface (Figure 19(a)). Incoming 6–14 s waves were damped initially by a 2.5 km wide band of seven-tenths pack ice, but suffered little attenuation through a similar width of brash and slush ice. An ice concentration greater than six-tenths in the nearshore was required for effective wave attenuation. Grounded ice blocks provided some protection to the upper beach but shifted breaking wave energy seaward, causing severe scour at the base of the beach (Taylor, 1981). Similar shifts in the locus of wave energy and ice entrainment to deeper water have been linked to expansion of an ice foot and nearshore ice complex in other places (e.g., Barnes et al., 1993, 1994). Kirk (1972) and Hansom and Kirk (1989) provided a model and discussion of the sequence of beach changes associated with sea-ice breakup and the melting of the ice foot with the onset of open-water wave activity in the Antarctic. Shore ice formation and sea-ice interaction with the coast comprise a wide variety of forms and processes (Forbes and Taylor, 1994). These include the following: • Nearshore ice scour, including • ice wallow pits and mounds and • grooved scour marks or grounding pits. • Ice ride-up and pile-up processes, producing • ice-push scours, furrows, grooves, and associated ridges or levees; • cobble or boulder pavements; • sand, gravel, or boulder ridges or ramparts;

• chaotic morphology in fine sediments; • anomalously high coastal barriers; • ice-cored beach ridges (grounded ice buried by subsequent storm gravels); and • beach deposits on bluffs. • Icefoot development on the beachface or cliff base • protecting the beach but creating a reflective wall near or slightly seaward of the low-water line; • pitted beach surfaces on melting; and • lower beachface anchor ice. • Nearshore ice complexes • incorporating an icefoot and landfast ice anchored by pressure ridges grounded on nearshore bars; • protecting the beach and shifting the breaking wave zone to deeper water; and • nearshore anchor ice. • Ice rafting associated with sediment adfreezing to buoyant floes or sediment deposition on ice, contributing to • formation of boulder-strewn tidal flats and platforms; • boulder barricades and garlands; and • anomalous coarse sediment deposition in shoreface, shelf, or deepwater settings. • Frazil ice formation • with associated sediment entrainment and rafting and • export of sediments and shoreface profile adjustment.

Polar Coasts • Bottomfast ice allowing over-ice flow and drainage • producing strudel scours in the shallow seabed off river outlets. Seabed scour, primarily by pressure-ridge keels, is a ubiquitous process on shallow Arctic continental shelves (e.g., Lewis, 1977; Barnes et al., 1984; Rearic et al., 1990; Héquette et al., 1995a; Ogorodov et al., 2005). The draft of ridge keels can extend to 50 m or more on the Canadian Beaufort Sea shelf (Lewis, 1977, 1978) and 65 m off Alaska (Barnes et al., 1984). Grounded pressure ridges occur in shallow water along the seaward edge of landfast ice, forming the stamukhi zone (Reimnitz et al., 1978), an area of intense ice scour. In Greenland waters, Baffin Bay, the Labrador Sea, Svalbard, the Antarctic and the sub-Antarctic islands, scour by iceberg keels is a common phenomenon with important implications for benthic communities and, in the Arctic, for seabed infrastructure (e.g., Woodworth-Lynas et al., 1991; Conlan and Kvitek, 2005; Laudien et al., 2007; Smale et al., 2007, 2008). Iceberg mobility is constrained by fast ice, leading Smale et al. (2008) to suggest that a reduction in sea ice may lead to increased scour in the future. Along Arctic lowland coasts, scouring by pressure-ridge keels or fragments has been linked to enhanced scour in the stamukhi zone and there has been some speculation on the role that ice scour on the shoreface may play in coastal stability (Reimnitz et al., 1978; Barnes et al., 1984; Héquette and

263

Barnes, 1990). Except where the coast is entirely composed of rock (or ice), shallow scour by grounding sea ice in the nearshore is a near-ubiquitous process in polar regions (Figure 20(a) and 20 (b)). Reimnitz et al. (1977) estimated that the entire seafloor of the Alaskan Beaufort Sea shelf is reworked by ice scour over a 50-year interval. The persistence of the resulting morphology, like that of ice push and melt-out pits on the beach face, depends on the frequency and intensity of subsequent wave action. In the shallow shoreface and nearshore zone, hydraulic scour around grounded or near-grounded ice blocks under storm wave conditions may be augmented by flow acceleration (Ogorodov et al., 2005) and a pulsating motion of the ice blocks induced by wave oscillation (Hume and Schalk, 1976). Reimnitz and Kempema (1982) described an array of ice-wallow depressions and mounds (50–100 m in diameter with a relief of 2–3 m) on the shoreface of Reindeer Island on the north coast of Alaska. The depressions were much larger than the dimensions of indi­ vidual ice blocks and both smoother and 2–3 times deeper than produced by fair-weather grounding and bottom scour. Landward ice motion in the nearshore occurs through fric­ tional wind stress or stress transmitted through the ice pack (e.g., Dionne, 1992; Mahoney et al., 2004). With sufficient stress, the ice may ride up or pile up across the beach. Ride-up involves fracturing but little deformation of the floating ice, whereas pile-up develops when frictional or compressive resistance leads to buckling failure that results in vertical growth of an ice

(a)

(b)

(c)

(d)

Figure 20 Ice-push and ice pile-up: (a) ice thrusting onto a low barrier island, scouring nearshore and driving sediment onto the beach, west coast of Banks Island, NWT; (b) ice pile-up with heavy sediment load, evidence of ice scour in the nearshore and landward transport; note delicate imprints of ice higher on beach prior to melting; height of pile-up ridge ∼ 5 m, west coast of Banks Island, NWT; (c) ice-pushed ridge surrounding one of the Polynia Islands, northwest Canadian Arctic Archipelago; and (d) thick multiyear ice ride-up and collapse over ice-pushed shore ridge, west coast of Prince Patrick Island, NWT. Photo sources: (a-b) DLF, 2002; (c-d) courtesy R.B. Taylor, 1990, 1992.

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Polar Coasts

(a)

(b)

(c)

(d)

Figure 21 Ice imprints on beaches and boulder flats: (a) subtle grooved imprint of ice ride-up on low spit east of Mercy Bay, M’Clure Strait, NWT; (b) melt-out pits in a fine gravel beach near Sachs Harbour, NWT; (c) polygonal depressions in a boulder pavement, South Beaches, Byers Peninsula, South Shetland Islands; and (d) ridges, depressions, and ice-pushed furrows in boulder pavement at mid-tide, South Beaches, Byers Peninsula, South Shetland Islands. Photo sources: (a-b) DLF, 2006, 2002; (c-d) JDH, 1976

ridge (Figure 20; Kovacs and Sodhi, 1981, 1988). Similar defor­ mation at converging floe contacts in deeper water produces the pressure ridges discussed above. Onshore motion of ice produces grooved scour marks, push ridges and levees, mounds, cobble or boulder pavements, and boulder ramparts (Figure 21) (Nichols, 1953; Hume and Schalk, 1964; Dionne, 1978, 1985, 1992; Barnes, 1982; Hansom, 1983b, 1986, 2005b; Forbes and Taylor, 1994). Landward motion of thick multiyear ice in the northwest Canadian Arctic Archipelago forms large shore ridges, primar­ ily, but not exclusively, on the outer Arctic coast (Figures 20(c) and 20(d)) (Hudson et al., 1981; Taylor and Hodgson, 1991; Forbes and Taylor, 1994; Hodgson et al., 1994). Downward flexure of ice feeding into a pressure ridge or shore ice pile-up has been cited as a mechanism for nearshore scour and land­ ward sediment transport, which may produce anomalous barrier crest elevations (Reimnitz et al., 1990). Ice ride-up has been reported extending as much as 90 m inland in ice as thin as 0.3 m (Alestalo and Häikiö, 1976) and elsewhere to more than 100 m (Taylor, 1978; Kovacs and Sodhi, 1980) or 150 m or more (Ogorodov, 2005b). The effects of ice ride-up are often found to be superficial (Kovacs and Sodhi, 1980; Kovacs, 1983), although severe damage to coastal infra­ structure has been reported from some mid-latitude locations. On mud coasts of the northwest Canadian Arctic Archipelago,

ice ride-up produces a distinctive shore type, exhibiting a chaotic morphology of mounds and hollows (Taylor and Forbes, 1987). Pile-up ridges can grow incrementally to heights of a few to many meters (Taylor, 1978; Kovacs and Sodhi, 1980, 1988). Most often, this occurs in ice <1 m thick, but Taylor (1978) and Taylor and Hodgson (1991) reported pile-up involving ice up to 2 m thick (Figure 20(d)). Pile-up heights as high as 20 m are common (Taylor, 1978); but heights as much as 36 m (Sverdrup, 1904) and 50 m (Zubov, 1943) have been reported. Ice pile-up rarely extends more than 10–15 m onshore but can cause significant damage. Pile-up typically occurs rapidly (30 min) and has been known to cause fatalities. There are numerous documented cases of infrastructure damage from the Pechora, Baltic, and Labrador seas, the Gulf of St. Lawrence, the eastern Canadian Arctic, and the Beaufort Sea in Canada and Alaska (e.g., Alestalo and Häikiö, 1976; Kovacs and Sodhi, 1981; Forbes and Taylor, 1994; Mahoney et al., 2004; Ogorodov, 2005b). An extensive shore-ice pile-up ridge 10 m high was documented along the outer coast of Shingle Point, a seasonal fishing and whaling settlement on the Yukon coast (Lewis and Forbes, 1976), and ice is known to have overtopped a coastal cliff 9 m high in Alaska (Kovacs and Sodhi, 1980). Ice remaining on the beach after a ride-up event may be buried under beach sediment. Subsequent meltout combined with ice push mounds creates a severely pitted morphology (Figure 21(b)) (Nichols, 1961, 1968; Moign and Guilcher,

Polar Coasts

1967; Greene, 1970; Short and Wiseman, 1974; Short, 1976; Taylor and McCann, 1976; Reinson and Rosen, 1982). Pits up to 2 m in diameter can result from partial burial of multiyear ice blocks (Taylor and McCann, 1983). Ice-foot development can be important on high-latitude coasts where it provides partial protection of the shore and beach in the event of open water developing along the coast. The formative processes and morphology can be quite variable, depending on the shore slope, tidal range, wave conditions, and ice dynamics during growth of the ice foot (Figure 19). Based on observations in Antarctica, Wright and Priestley (1922) proposed a five-part classification for the ice foot: • ‘tidal platform ice foot’ (intertidal), formed by freezing swash sheets; • ‘storm ice foot’ (supratidal) formed by freezing spray; • ‘drift ice foot’, formed by accumulation of ice on the beach, consolidated by freezing of water surging between the ice blocks; • ‘pressure ice foot’, formed by ice ride-up or pile-up; and • ‘stranded-floe ice foot’, in which beached bergy bits or other large floes are incorporated into the ice foot. Much of the subsequent literature emphasizes the protective role of the ice foot, although some note the potential for removal of sediment by ice-foot fragment rafting (Koch, 1928; Joyce, 1950; Zumberge and Wilson, 1953; Feyling-Hanssen, 1954; Rex, 1964; McCann and Carlisle, 1972; Marsh et al., 1973; Moign, 1976; Owens, 1976; Taylor and McCann, 1976; Evenson and Cohn, 1979; Barnes et al., 1994). Moign (1976) highlighted the differences between beach and cliff-base ice-foot development where the latter may be augmented by snowbank accumulation (Figure 19(d)). Rex (1964) emphasized the incorporation of sand and gravel with frazil ice in a ‘gravel– sand–ice foot’, typically bedded with individual units 0.1–0.5 m thick and up to 2.4 m thick at Barrow, Alaska. Described by the Inuktitut term ‘kaimoo’, this structure also occurs elsewhere (e.g., Taylor and McCann, 1976) and generally melts in situ, leaving incorporated sediment in place on the beach. Where there is open water beyond the nearshore, wave spray may promote a vertical wall on the outer rim of the ice foot that can contribute to scour at the base of the beach or the inner nearshore (Dozier et al., 1976). The width and character of the ice foot are affected by tidal range and nearshore ice conditions. Microtidal beaches of the northwestern Canadian Arctic Archipelago have minimal ice-foot development (Taylor and McCann, 1976). By contrast, at macrotidal sites such as Iqaluit, a substantial horizontal ice foot develops at the higher high-tide level, while ice remains mobile on extensive boulder-strewn tidal flats to seaward (Figure 19(b) (Dale et al., 2002). Incomplete summer melting of the ice foot with wave run-up and sedimentation can lead to the development of ice-cored beaches (Nichols, 1961; Sempels, 1987) and may play a role in the anomalous emplacement of gravels on top of low coastal bluffs along the North Slope in Yukon and Alaska (Forbes and Taylor, 1994). Where pressure ridges ground over shallow nearshore waters or on nearshore bars, an extensive ‘nearshore ice complex’ can develop with an inner ice foot, a band of fast ice, and an outer grounded ridge (Zumberge and Wilson, 1953; Barnes et al., 1994). This can shift the locus of

265

wave erosion well out from the beach, leading to downcutting of the nearshore profile (Bernatchez and Dubois, 2004). Allard et al. (1998) described a process in which ice-foot development on an erosional tidal platform cut into postglacial marine clays causes downward freezing and formation of segre­ gation ice in underlying sediments. This results in disruption of the clay structure and subsequent thaw liquefaction in early summer, leading to loss of sediment and further erosion of the tidal flat. In addition, the freezing front beneath the ice foot impedes groundwater and surface water flow during winter, leading to forced seepage that produces frost blisters, surface icings (naleds), and lenses of intrusive ice in the upper tidal zone. Sub-tidal anchor ice is widely observed in the shallow nearshore at many high-latitude sites, at times persisting throughout the summer. Sadler and Serson (1981) provided a detailed description and a conceptual model to account for the formation of sub-tidal anchor ice in the vicinity of Resolute Bay, Nunavut. They found anchor ice salinities less than 0.2 (practical salinity scale) (contrasted with 3–8 in sea ice) and suggested that the ice is formed by extrusion of freshwater moving seaward under pressure between the permafrost table and a downward freezing front beneath the beach surface at the start of freeze-up (cf. Mackay, 1972). A similar form of anchor ice, with salinity between 0.1 and 1, was described from the Cape Hatt area of northern Baffin Island by Sempels (1987). Anchor ice also forms by aggregation of frazil ice adhering to submerged surfaces down to the maximum depth of super­ cooling, which can be as deep as 30 m in the Ross Sea and 20 m in the Alaskan Beaufort Sea (Dayton et al., 1969; Reimnitz et al., 1987). When anchor ice formed in this way breaks free after formation of a surface ice cover, it causes bottom distur­ bance by carrying off adfrozen sediment or epibenthic fauna and provides an important mechanism for incorporation of sediment into the surface ice cover, after which it can be rafted great distances (Reimnitz et al., 1987). Frazil ice forms under turbulent supercooling conditions during autumn storms with strong winds over open water. Frazil ice can also be produced at the interface between fresh­ water and cold saline water during spring river discharge under an ice canopy (Golovin et al., 1999). Large volumes of disk-like crystals 1–5 mm in diameter and <0.1 mm thick can be produced very rapidly (Martin, 1981). The frazil can accumulate to thicknesses of 4 m or more beneath an ice canopy adjacent to the area of frazil ice formation and, as noted above, can adhere to supercooled substrate, forming pillow-like accumulations of anchor ice adhering to frozen sediment (Tsang, 1982; Reimnitz et al., 1987; Kempema et al., 1990). As the turbulence diminishes following a storm, frazil flocs rise to the surface to form slush ice (Reimnitz and Kempema, 1987a). In addition, anchor ice may break loose and float to the surface, carrying sediment to be incorporated into the developing ice cover (Kempema et al., 1989, 1990). Reimnitz and Kempema (1987a) showed that congealing slush ice can carry a sediment load as high as 1000 m3 km−2. This mechanism may account for some of the very high erosion rates along the Alaskan coast (Reimnitz and Kempema, 1987b). Barnes et al. (1993) pointed to frazil ice formation and ice rafting as a highly effective sediment trans­ port process in Lake Michigan. Reimnitz and Kempema (1987a) convincingly demonstrated that sediment in the fast-ice canopy between the Colville and Sagavanirktok rivers

266

Polar Coasts

in the 1978–79 winter was 16 times the annual sediment discharge from the rivers, and suggested that it was derived during a slush-ice formation event on the inner shelf nearly 400 km to the east off the Canadian coast and then trans­ ported west. Downward freezing of fast ice in winter along high-latitude coasts can create bottomfast ice in depths less than 0.5–2 m, depending on the latitude and local climate (which determine the late-winter ice thickness). Where the ice is bottomfast, cold air temperatures enable seabed freezing, preserving seabed per­ mafrost and the bond between the bottomfast ice and the bed (Solomon et al., 2008). In spring, this ice typically melts from the surface, remaining bonded to the nearshore seabed as anchor ice (Figure 22(a)). Ice action on intertidal flats and rock platforms is an impor­ tant process in some regions (e.g., Hansom, 1983a, 1983b). In glaciated regions with large numbers of boulders and a mod­ erate to large tidal range, extensive boulder-strewn tidal flats can develop (Figures 22(b)–22(d)). Dionne (1981a, 1981b, 1984, 1985, 1988) has been a prolific observer of ice-pushed and ice-rafted deposits in the St. Lawrence River Estuary and Hudson Bay regions. The boulders in such settings are subject to movement by ice through rolling, sliding, or rafting (Drake and McCann, 1982; Forbes and Taylor, 1994; Dale et al., 2002)

and furrows, push mounds, and less common lateral ridges widely observed on boulder-rich flats attest to this movement (Dionne, 1988). Rosen (1979), working in Labrador, pub­ lished a study of the processes leading to the formation of boulder barricades (Tanner, 1939) at the outer limits of a tidal flat or low-tide terrace (Figure 22(d)). These features have been reported from the Baffin Island region, Newfoundland, and Scandinavia as well. Some of the most spectacular have been found in Ungava Bay, an area with a tidal range of almost 16 m (Lauriol and Gray, 1980). McCann et al. (1981), Gilbert and Aitken (1981), and others have noted a tendency for boulders to cluster in mounds and polygonal ridges referred to as ‘garlands’. The origin of these distinctive features is poorly understood, but once established this geo­ metry may be self-sustaining through packing and floe-scavenging processes (Forbes and Taylor, 1994). Cobble and boulder pavements are another form of packing that occurs where floating ice impacts dominate over wave processes (Hansom, 1983b, 1986). These can also display a polygonal geometry produced as individual stranded ice blocks rotate (Hansom and Kirk, 1989), suggesting a possible similarity with small-scale garlands, although (unlike garlands) the pave­ ments occur only where there is a paucity of mud. They are found across a wide range of latitude in both hemispheres,

(a)

(b)

(c)

(d)

Figure 22 Anchor ice and boulder-strewn tidal flats: (a) anchor ice in early summer at Qikiqtarjuaq, Baffin Island, Nunavut; (b) general view of tidal flats at low tide, Pangnirtung, Baffin Island, Nunavut; (c) Pangnirtung flats with barricade at right; note 1-m red scale upright against boulder in right background; and (d) boulder barricade at outer limit of Pangnirtung tidal flats. Photo source: DLF, 2004

Polar Coasts

from Newfoundland and Iceland to the northern archipelago in the Arctic and from South Georgia to Victoria Land in the Antarctic (Figures 21(c) and 21(d)). Boulder tidal flats, boulder barricades, garlands, and pavements tend to be best developed in somewhat sheltered settings dominated by tidal currents and ice interaction, with waves playing a minor role. Tanner (1939) contrasted the limited development of boulder barricades in the microtidal Baltic with their extensive occur­ rence on the mesotidal coasts of Labrador and the Barents Sea, where the tidal range exceeds 2 m. However, Gilbert and Aitken (1981) noted the modest development of boulder barricades at Clyde River, Nunavut, where the tidal range is 0.6 m and sug­ gested that the supply of fine sediment may play a role in determining the relative predominance of boulder flats or barricades.

3.10.3.3 Erosion and Sedimentation Processes on Polar Coasts Waves and currents are important agents of sediment entrain­ ment and transport on all polar coasts, except those that are perennially ice bound without summer open water (see Section 3.10.4.1). This section examines wave, current, and wind processes operating largely independent of sea ice on sedimentary coasts. The following section then turns to a consideration of erosion processes conditioned by frozen ground and ground ice. Much of the Arctic coast is microtidal, with spring tidal ranges <1 m, and tidal currents are weak. However, meteorological effects in some areas such as the southern Beaufort Sea can account for 80% of the variance in water levels and can generate storm surges and downwelling conditions along the coast. By contrast, macrotidal conditions prevail in some areas: the tidal range at springs in Mezen Bay (Barents Sea) amounts to 11 m; in Frobisher Bay on Baffin Island it is 12 m; and in Ungava Bay on the south side of Hudson Strait it reaches 16 m (equaling the world’s previously recognized highest tides in the Bay of Fundy, both regions being characterized by winter sea ice). Strong longshore tidal currents in some regions such as Foxe Basin can exert a major influence on the nearshore circulation and influence bidirectional longshore gravel sediment transport under variable storm conditions (Manson and Forbes, 2008). The literature on high-latitude coastal forcing and sediment transport on the Arctic shoreface is somewhat limited (and virtually absent in the Antarctic), although observations of storm impacts on coastal geomorphology are more extensive. Among the earliest detailed studies of coastal wave processes in an Arctic setting was a large project reported by Wiseman et al. (1973) and co-workers (e.g., Short, 1975; Short et al., 1975) along the Alaska North Slope. Preceding and overlapping with this work were a number of papers reporting on coastal impacts of large storm events and long-term coastal erosion measure­ ments in the same region (Hume and Schalk, 1967, 1976; Harper, 1978; Reimnitz and Maurer, 1979a). Reimnitz and colleagues continued with a succession of innovative studies of coastal and shelf processes for a number of years (e.g., Reimnitz et al., 1974, 1978, 1987, 1990; Barnes, 1982; Reimnitz and Kempema, 1982, 1983, 1987a; Barnes and Reimnitz, 1988; Reimnitz and Barnes, 1988). During the 1990s, work was initiated on nearshore processes along the Tuktoyaktuk Peninsula in the Canadian Beaufort Sea. Studies

267

by Héquette and Hill (1993, 1995) and Héquette et al. (2001) focused on shoreface and nearshore wave and current forcing of sediment transport. These showed that bottom return flows under downwelling circulation during storm surges with wave setup are important agents of offshore sediment dispersal along this sandy coast. Héquette et al. (2001) found differences in the strength of downwelling currents and sediment transport between sites with backshore bluffs and sites with low sandy barrier beaches overtopped during storms. Evidence for onshore sediment movement by ice push on the shoreface was reported by Héquette and Barnes (1990) and Héquette et al. (1995a), but there are no quantitative estimates of the transport. Although severe storms are frequent in the Antarctic, there are surprisingly few accounts of the effects of storm events on the coast, probably because many coasts are infrequently visited and are predominantly ice or rock. However, in 1961 and 1976, cyclonic depressions on the south coast of South Georgia reached 948 and 970 hPa, respectively, generating storm surges and associated waves that destroyed field camps and stripped small gravel beaches down to bedrock (Hansom, 1981). In the Antarctic, Butler (1999) highlighted the importance of orientation with respect to wind and waves. South-facing beaches (exposed to predominant katabatic winds from the continent) are more likely to show ice-thrust features, whereas north-facing beaches (exposed to the greatest wave fetch and where ice is blown offshore) show a dominance of wave action. He also documented differences in clast rounding, sorting, imbrication, and beach slope between gravel beaches in McMurdo Sound exposed to more or less open water and resulting wave energy, contrasting 62% ice-free conditions at Cape Bird with 3% at Marble Point. Kirk (1972) regarded Antarctic beaches as natural hydrodynamic models, producing a new and reorganized set of beach forms over the annual freeze-up and break-up cycle. The relative order associated with wave processes such as sediment sorting and beach ridge development is covered ice on freeze-up. On break-up of the sea ice and disintegration of the ice foot, the bulldozing of floating ice moves beach sediment in a nonselective way to produce disorganized fabrics and landforms before waves pro­ cesses temporarily hold sway again. Beaches in the same area with differing exposure often dis­ play differences in mean crest elevation resulting from differing wave climate and run-up. In the same way, changes in wave climate and run-up potential resulting from more or less float­ ing ice cover may produce variable beach crest elevations over time (St-Hilaire-Gravel et al., 2010), although ice push can also be effective in driving sediment to higher levels (Reimnitz et al., 1990). It is thus apparent that crest elevation of polar beaches cannot be used everywhere as a direct surrogate for mean sea level in interpreting past changes in sea level from emerged beach deposits. Nevertheless, trends in beach crest elevation on a prograded barrier on the west coast of Banks Island (Forbes et al., 2004) and on gravel forelands in Navy Board Inlet and at Cape Charles Yorke (Figure 11(c) and 11(d)) both reflect slow rise in relative sea level during their formation. Wind is an effective transport agent at high latitudes where limited vegetation cover results in low surface roughness and sediment binding capability. Wind moves snow and ice crystals as well as sediment and can be an effective erosional and weathering agent (e.g., Harrowfield, 2006). On wind deflation

268

Polar Coasts

surfaces with partially embedded pebbles or cobbles, polished ventifact surfaces can develop. Drifts of niveo-eolian interbedded snow and sediment occur behind exposed dunes or beaches, forming a large component of fresh sedimentation in some coastal dune systems (Bélanger and Filion, 1991; Ruz and Allard, 1994, 1995). Reimnitz and Maurer (1979b) reported extensive wind transport of sand across coastal gravel barriers in northern Alaska into the back-barrier lagoons and this pro­ cess may be even more effective where wide sandy barriers occur, such as on the Tuktoyaktuk Peninsula (Figures 23(a) and 23(b)). Small coastal dunes are common in this region where the sandy coastal bluffs are generally low (Ruz, 1993; Hill et al., 1995). Indeed, since niveo-eolian processes are common in many places in the Arctic where proglacial outwash plains or unvegetated sandy substrates abut the coast (see Koster (1988) for a review), coastal dunes may be unrecorded as such but probably exist (Figure 23(c)). A large sandy barrier on the Cape Aston foreland of east Baffin Island is capped by supply-limited transverse dunes, with a deflation lag surface of ventifacts in the troughs between the dunes (Figure 23(d)). Elsewhere in high latitudes, the occurrence of coastal dunes is sporadic. In Antarctica, sand dunes are known from the oases and Dry Valleys (Bourke et al., 2009) but are rare elsewhere. In South Georgia, where a warmer and wetter climate allows upright vegetation to grow, low dunes occur landward of sand and gravel beaches fronting glacifluvial outwash plains. However, in general, coastal dunes are rare in polar settings, possibly reflecting the limited sand supply in many polar

coastal environments as well as the restricted capacity of ground-hugging vegetation to stabilize windblown sand. Bio-erosion and cementation is generally considered a minor factor in cold regions. Smith and Bayliss-Smith (1998) reported substantial rates of coastal erosion by kelp plucking on Macquarie Island in the Southern Ocean. At this site, exposed to large storm waves and energetic swell, angular rock fragments up to 74 kg, assumed to have been plucked from the seafloor, and boulders up to more than 160 kg were recorded in masses of bull kelp (Durvillaea antarctica) cast on the beach after storms or swell events. The authors estimated an annual erosion rate of 1.56 tonnes km−1 in this area. In a radically different setting, the boulder tidal flats of Frobisher Bay on Baffin Island, Dale et al. (2002) noted that incorpora­ tion of kelp fronds anchored on large clasts may be one mechanism of entrainment. In the Antarctic, various species of penguins nest in vast rookeries that the birds access along clearly rutted, polished, and smoothed pathways over shore platform, cliff, and scree (Hansom and Gordon, 1998). Beach sediments may in time become cemented with guano, partially immobilizing them in the event of wave action, as occurs at Ridley Beach, Cape Adare (Figure 16(b)).

3.10.3.4

Coastal Permafrost and Erosion of Ice-Rich Shores

Permafrost and seasonally frozen ground in the coastal zone exert a profound influence on high-latitude coasts in both polar regions. Most of the literature relates to the Arctic

(a)

(b)

(c)

(d)

Figure 23 Arctic coastal dunes: (a) broad, low, sandy barrier on the Tuktoyaktuk Peninsula; (b) dunes spilling over low tundra terrace, Tuktoyaktuk Peninsula; (c) low dunes dissected by washover channels, De Salis Bay, Banks Island, NWT; and (d) transverse dunes on large barrier beach at Cape Aston, Baffin Island, Nunavut. Photo sources: (a-c) DLF, 1992, 1984, 2006; (d) courtesy R.B. Taylor, 1984

Polar Coasts

where, unlike the Antarctic, thick piles of unlithified sediments are exposed along the coast (Figure 24). Permafrost (defined as ground temperature remaining below 0 °C for 2 years or more) may be ice bonded, ice bearing (containing zones or lenses of ice), or ice free. Ice-bonded sediments are described as frozen and permafrost without ice is considered unfrozen. The circum-Arctic distribution of permafrost and ice-bonded or ice-bearing sediments has been mapped most recently by Brown et al. (1998) (Figure 4) and encompasses almost the entire Arctic coast except for a small region in western Russia. In the Antarctic, although all the ice-free areas are affected by permafrost, mapping of the interior and offshore reveals a surprisingly restricted total area (Figure 5) (Bockheim, 1995). The widespread distribution of Arctic subsea permafrost has been mapped by Brown et al. (1998) and Osterkamp (2001). The extent is somewhat speculative, based on limited geophy­ sical data (e.g., Blasco, 1995; Rekant et al., 2005) and thermal modeling (e.g., Lachenbruch and Sass, 1982; Hubberten and Romanovskii, 2003; Romanovskii et al., 2005), supported by a growing body of data from offshore drilling (e.g., Osterkamp et al., 1989; Dallimore 1991; Dallimore and Taylor, 1994; Overduin et al., 2007; Rachold et al., 2007). Subsea ice-bearing permafrost extends as much as 600 km offshore in the Laptev and East Siberian seas where water depths are predominantly <50 m (Overduin et al., 2007). Though less extensive in other areas, subsea permafrost extends west to the Pechora Sea (Bondarev et al., 2005) and east to the Chukchi and Beaufort seas off Alaska, Yukon, the Mackenzie Delta, Tuktoyaktuk Peninsula, and Banks Island (Hunter et al., 1976, 1978; Sellmann and Hopkins, 1983; Osterkamp, 2001). In the Antarctic, the subsea permafrost mapped by Bockheim (1995) is restricted to a few areas of the Bellingshausen Sea in Western Antarctica and below the Rönne–Flichner Ice Shelf in the Weddell Sea (Figure 5). Frozen ground typically contains some unfrozen water, more so if the pore water is brackish or saline. In coastal areas of crustal uplift, where the soils consist of relict marine silt and clay, salinities can exceed 30 (practical salinity scale), reaching >44 in some areas such as the community of Clyde River, Nunavut (Hivon and Sego, 1993). At these concentrations, saline permafrost represents a foundation hazard for buildings and other infrastructure (Tsytovich et al., 1978; Nixon, 1988) as bearing capacity can be reduced by a factor of 2–3 and creep rates can increase dramatically (Ogata et al., 1983). On an eroding coast and shoreface, saline pore water dif­ fuses into nearshore subsea sediments, depressing the freezing point, and the interface between unfrozen and underlying fro­ zen sediments deepens seaward (e.g., Hill and Solomon, 1999; Forbes, 2004; Overduin et al., 2007). The slope of the interface is a function of the coastal erosion rate, the water temperature and salinity, and the rate of downward penetration of unfrozen saline water (Overduin et al., 2007). In the Arctic, where ther­ mokarst lake basins and their underlying taliks (unfrozen zones) are overtaken by transgression, the slope of the unfrozen–frozen interface may deepen more steeply (Holmes and Creager, 1974; Rekant et al., 2005; Overduin et al., 2007). In addition, subsea thaw of permafrost deposits with massive ice can produce rapid local seabed subsidence, as much as 3–10 m locally (Dallimore et al., 1988, 1996; Wolfe et al., 1998).

269

The processes of coastal erosion in ice-bonded sediments, most common in transgressive coastal plain settings of the Siberian and western North American Arctic, involve various combinations of thermal and mechanical effects. These include ‘thermal abrasion’ (Aré, 1980, 1988), undercutting, thaw con­ solidation, mass wasting, wave reworking, and thermal denudation (thermokarst) processes (Figure 24). With high proportions of excess ground ice, typically fine-grained sedi­ ments with high silt content, low topographic gradient, and additional processes such as frazil ice entrainment (see above), rates of coastal retreat can be very high (Aré, 1996). For exam­ ple, in a discussion of the preservation of subsea permafrost in the Laptev Sea region, Overduin et al. (2007) quoted an esti­ mate by Aré (1980) that southward retreat of the shoreline averaged 35–90 m a−1 during the postglacial marine transgres­ sion, particularly during the Holocene climatic optimum. However, as sea level stabilized, the rate slowed down and the coast is thought to have retreated another 10–40 km over the past 5000 years. These rates are still considerable and are driven in part by the fact that much of the backshore terrain in this region consists of ice complex deposits typically compris­ ing 80% ice by volume and extending below sea level. Erosion of ice-rich coastal sediments can be rapid during major storm events (e.g., Hume and Schalk, 1967; Solomon et al., 1994; Solomon and Covill, 1995). A high proportion of ice decreases the volume of sediment to be removed by waves and currents, facilitating removal of material by even modest waves. Vasiliev et al. (2005) showed a good correlation between cliff retreat rate and total wave energy, but a weaker correlation with the number of storm days per year. They concluded that storms are less important in the Barents and Kara seas and that coastal retreat is driven primarily by waves <1 m high removing fine sediments and maintaining exposures of frozen sediments to activate thermal erosion processes. Along the Alaska coast, Anderson et al. (2009) documented rapid retreat (15–25 m yr−1) of low bluffs in ice-rich silts. Time-lapse imagery showed that, with little sand or coarser material to form protective beaches, the bluff retreated by episodic block failure (toppling) driven by continuous thermal niche development related to warm sea-surface temperatures. Shore-zone profile incision can be impeded by ice-bonded sediments, necessitating the development of combined thermal–mechanical models to simulate the process (e.g., Nairn et al., 1998). Nevertheless, Arctic shoreface profiles are statistically similar to profiles in lower latitudes, indicating the predominant role of waves (Aré et al., 2008). Other forms of erosion in ice-rich deposits include active-layer detachment slides or flows and retrogressive thaw flow RTF failures. Erosion of coastal bluffs on the Arctic coastal plain takes a variety of forms. In places, exposures of the Ice Complex form high vertical cliffs at sea level (Figure 3(d)). Elsewhere, vertical exposures in RTF headwalls feed water and sediment to mudflows evacuating sediment from the RTF bowl, often downslope across the beach and directly into the water (Figure 24(a)). Some bluffs stand near-vertical and lose sedi­ ment through thaw sloughing, active-layer detachment, or by surface runoff forming gullies (Figure 24(d)) (Kizyakov et al., 2004). Thermal abrasion and wave action can form deep undercuts (thermo-erosional niches) at the base of near-vertical cliffs (Figures 24(b) and 24(d)). These lead ultimately to block slipping or toppling, where the blocks are often defined by the

270

Polar Coasts

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(d)

Figure 24 Erosion processes of the Arctic coastal plain: (a) multiple generations of retrogressive thaw flow failures at King Point, Yukon; (b) deep niche development beneath ice-rich cliff following a major summer storm, Tuktoyaktuk, NWT; (c) collapse of undercut blocks defined by ice wedge thaw or failure, Kay Point, Yukon; and (d) wave undercut and surface sloughing along cliff south of De Salis Bay, Banks Island, NWT. Photo sources: (a) DLF, 1992; (b) courtesy S.M. Solomon, 2000; (c-d) DLF, 1975, 2006

axes of polygonal ice wedges (Forbes and Taylor, 1994). Hoque and Pollard (2009) developed an analytical model for block failure of a permafrost bluff with a developing thermo-erosional niche. They identified several distinct failure modes, differentiating between sliding and toppling, between vertical and inclined plane failure, and between conditions with or without ice wedges (Figures 24(b) and 24(c)). They also provided computations of critical niche depth and ice-wedge distance for failure with a given cliff height and material strength and found, in general, a greater tendency to toppling on lower bluffs. The rates of coastal retreat at Arctic coastal plain sites in Siberia and North America are highly variable from <1 to >30 m a−1 (e.g., Mackay, 1975; Harper, 1978, 1990; Aré, 1980, 1988, 1996; Reimnitz et al., 1985; Héquette and Barnes, 1990; Héquette and Ruz, 1991; Aré et al., 2005; Jorgenson and Brown, 2005; Solomon, 2005; Vasiliev et al., 2005; Mars and Houseknecht, 2007; Overduin et al., 2007; Lantuit and Pollard, 2008; Jones et al., 2008, 2009; Lantuit et al., 2008a, 2008b, 2009, 2011; Lantuit and Overduin, 2010). While some studies have found no acceleration of erosion rates (e.g., Solomon, 2005; Lantuit and Pollard, 2008), others have argued for a marked increase in erosion rates that may be associated with a combination of less sea ice (more open water) and warmer sea-surface and ground temperatures, promoting rapid thermal erosion of ice-bonded silts (Wobus et al., 2008, 2009; Anderson et al., 2009; Overeem et al., 2009; Sánchez-Garcia

et al., 2009). Much of the permafrost in Arctic coastal regions is warm (close to 0 °C) and is therefore sensitive to small envir­ onmental changes including warming of air and sea-surface temperatures. There is evidence for warming in the Arctic Ocean (Bindoff et al., 2007), suggesting a potential for enhanced niche development and bluff erosion (Nairn et al., 1998) as well as subsea permafrost thaw and profile adjust­ ment (Dyke, 1991; Dallimore et al., 1996). Where high erosion rates prevail, the rates adjusted to account for the proportion of the year when erosional processes are active are among the most rapid encountered at any latitude (Reimnitz et al., 1985; Aré, 1996; Reimnitz and Aré, 1998). Further insight may be gained from modeling studies. While some have been pursuing this approach for some time (e.g., Kobayashi, 1985; Nairn et al., 1998; Kobayashi et al., 1999; Leont’yev, 2003, 2004a, 2004b), there is a new impetus from a number of groups to develop more effective models for Arctic coastal erosion.

3.10.4 Morpho-Sedimentary Features of Polar Coasts Polar coasts encompass a great diversity of coastal types, land­ forms, and materials. Factors affecting coastal morphological and sedimentary outcomes include general bathymetric and topographic setting, geodynamics and relative sea-level trends, environmental forcing (winds, waves, and currents), geology and sediment supply, and ice-related processes. In rock-bound

Polar Coasts

regions, these range from high rock cliffs and fjord walls, to cliffs with large talus ramps or shore platforms, to the lower-relief rocky, gravel-bound coasts of the central Canadian Arctic, Svalbard, northwest Russia, and parts of the Antarctic coast (Figures 3a, 8b, 9a, 15b–d, and 16). On the Arctic coastal plain, there is a common set of quite diverse coastal forms that occurs across the entire region. These include coastal cliffs exposing frozen sediments with varying excess ice content, exposures of massive ice in headwalls of retrogressive failures, undercut polygonal blocks defined by ice wedges, submerged ice-wedge polygonal tundra, and a vari­ ety of sand and gravel beaches, spits, and barrier islands (Figures 3(b), 3(d), 10, and 24). Perennially ice-protected shores of the northwest Canadian Arctic Archipelago may show little or no evidence of coastal wave reworking (Taylor and Forbes, 1987; Forbes and Taylor, 1994). Similar peren­ nially ice-bound shores exist in the Antarctic, particularly close to the mainland coast and where islands lie close offshore, and within the Weddell Sea gyre on the eastern side of the Antarctic Peninsula. Glacial coasts can also be recognized as a distinctive class of polar coastal outcomes (cf. 00309). In the following sections, we expand briefly on the distinc­ tive morpho-sedimentary outcomes characteristic of ice-bound shores, transgressive coastal plain coasts, polar deltas, estuaries, and wetlands.

3.10.4.1

Ice-Bound Shores

Because of the circulation pattern in the Arctic Ocean, multi­ year ice is concentrated under pressure along the outer coast of the Canadian Arctic Archipelago from Prince Patrick Island north to the north end of Ellesmere Island and Greenland. Ice drift through the interisland channels is toward the south and many channels in the northwest archipelago remain

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quasi-permanently ice filled and do not open in summer. This results in severe fetch limitation and, apart from ice-pushed features and protruding deltas, the geomorphic expression of the shoreline is limited in much of the region (Taylor and McCann, 1983). In the Antarctic, multiyear ice is concentrated in the western part of the Weddell Sea and in the Bellingshausen and Ross seas. Taylor and Forbes (1987), in a detailed study of ice-bound coastal sites on Lougheed Island, distinguished three shore types: sand flat, mud flat, and scarred coasts (cf. Forbes and Taylor, 1994). The tidal range is less than 0.5 m and the shoreline in many places takes the form of very gently sloping algal mats or sand-flat surfaces extending into the water (Figures 25(a) and 25(b)). Where sand is more abundant, small waves may rework some sediment, forming small swash bars and sand berms up to 0.5 m high, but wind is also an effective transport agent. Mud-flat coasts are protected from ice impacts by very low nearshore gradients, but muddy coasts in more exposed loca­ tions can be subjected to heavy ice ride-up or pile-up, leading to severe deformation and burial of any vegetation. The resulting scarred morphology subsequently dries out and solidifies under freezing conditions, allowing it to persist for some time (Figures 25(d)). In this area of subdued topography, slope processes are limited, but active-layer detachment flows are common in some lithologies (Owens et al., 1981). Fetch-limited shores in more resistant terrain include col­ luvial slopes or poorly developed gravel beaches (McLaren, 1982; Taylor and Hodgson, 1991). Ongoing production of angular clasts by frost shattering, possibly combined with ice push (McLaren, 1982), contributes to the supply of beach gravel and influences the shape distribution. Limited clast rounding on ice-bound shores also reflects the restricted role of waves (Nichols, 1961; King and Buckley, 1968; McCann and Owens, 1969). Variations in the relative magnitude of

(a)

(b)

(c)

(d)

Figure 25 Ice-bound shores of the northwest Canadian Arctic Archipelago: (a) shore with negligible relief and little sand; (b) sandy shore showing very minor beach development; (c) ice impacting shoreline; and (d) scarred coast, a product of ice impact on a muddy shoreline. (a–c) Photo source: DLF, 1996

272

Polar Coasts

wave and ice activity are reflected in the shape of clasts con­ tained in Antarctic boulder pavements that display a latitudinal decline in the degree of rounding (Hansom, 1983b, Hansom and Kirk, 1989). Butler (1999) identified differences in shape, sorting, and beachface morphology between wave-dominated beaches and more protected sites in McMurdo Sound, Antarctica. South-facing (restricted fetch) sites have poorly sorted, angular to subrounded, poorly imbri­ cated gravels and less steep beachface slopes than north-facing (wave-exposed) beaches.

3.10.4.2

Transgressive Coastal Plain Shores

Arctic coastal plain shores, predominantly transgressive, com­ prise erosional and depositional systems resulting from rising sea level and marine erosion of frozen, but otherwise unlithi­ fied, coastal plain deposits (Ruz et al., 1992; Héquette et al., 1995b; Hill et al., 1995; Jorgenson and Brown, 2005; Overduin et al., 2007). The topography of the coastal plain (Figures 10, 14, 24, and 26) ranges from low-lying lake-studded plains to rolling hills, which may be associated with glacial moraines or glaciotectonic deformation (Mackay, 1959; Mackay et al., 1972) or Pleistocene eolian, lacustrine, marine, or other facies (e.g., Brigham-Grette and Hopkins, 1995; Murton et al., 1997; Murton, 2009; Schirrmeister et al., 2002, 2010). In areas of former glaciation, the coastal plain is partially dissected by relict outwash drainage channels. Modern rivers traverse the plain, particularly where it is narrow and backed by mountains, as along the North Slope of Alaska and Yukon. Drained lake sediments are widespread and form flat-lying terraces with ice-wedge polygons (Rampton, 1982, 1988). In places where the land is very low lying, rising relative sea levels have inun­ dated polygonal tundra, which can be seen maintaining its form on the shallow nearshore seabed (Figure 10(b)). Pingos (conical ice-cored hills developed in partially drained or infilled lake basins) dot the landscape (Figure 10(a)) and expose massive ice when intersected by the landward-moving coastline. In places, multiple generations of ice wedges form large ice bodies; elsewhere, massive segregated ice is present in coastal cliffs or in the headwalls of RTF failures (e.g., Mackay, 1966, 1971; Rampton and Mackay, 1971; Schirrmeister et al., 2010). Ice content in sediments of the Ice Complex in northern Siberia can amount to 80% or more (Overduin et al., 2007) and similar massive ice volumes can be found in places along the Canadian Beaufort Sea coast. Many parts of the Arctic coastal plain are studded with innumerable lakes, whether of kettle, thermokarst, or other origin. As the shoreline on a transgressive (submergent and eroding) coast intersects lake basins, a complex topography develops, as the lake basins become bays, the land between lakes continues to erode, and erosion products (sand and gravel) are reworked alongshore to form spits and barriers (Wiseman et al., 1973; Reimnitz et al., 1985; Ruz et al., 1992; Héquette et al., 1995b; Hill et al., 1995; Mars and Houseknecht, 2007). This leads to the formation of extensive lagoons or bays, often formed by coalescence of multiple basins, with spits or barrier islands developed along the outer coast (Figure 26) (Forbes et al., 1994; Solomon et al., 2000; Bryan et al., 2006). The barriers have low crest elevations and are subject to fre­ quent and extensive overwash (Figure 10(d)), leading to sediment transport into the back-barrier lagoons, while other

Figure 26 Intricate coastline developed by successive breaching of thermokarst lakes and development of low spits and barriers across the truncated embayments, Tuktoyaktuk lowlands. Photo source: DLF, 1992

sites with higher backshore terrain may lose sediment seaward under storm conditions (Héquette and Hill, 1993; Héquette et al., 2001). The erosional morphology of coastal cliffs or bluffs is a function of backshore lithology and geotechnical properties, ground ice content and distribution, cliff height, the depth of any thermo-erosional niche, the elevation of base of cliff (sub­ merged, at or near sea level, with or without a beach), and, above all, the erosional processes and their morphological signature.

3.10.4.3

Polar Deltas

Given the restricted surface runoff in Antarctica (except for the northern Antarctic Peninsula and sub-Antarctic islands where small deltas may occur), all polar deltas of any size are found in the Arctic. Distinctive features of Arctic deltas include (1) the presence of ice in permafrost on the delta plain and in the shallow nearshore and (2) seasonally persistent sea and river ice, which has a significant influence on hydrological and sedimentological processes. In smaller rivers with sufficiently shallow channels and limited lake or groundwater discharge, winter ice can fill the channels (Forbes, 1979). Where ground­ water flow continues during winter and is forced to the surface, extensive icings (frozen overflow) can develop, sometimes extending close to or reaching the coast (Reimnitz and Wolf, 1998). The extreme seasonality of Arctic deltas (Walker, 1998) results from the contrast between winter low flow (or zero discharge) and the spring break-up flood which can deliver a very high proportion of the annual runoff (Church, 1974; Davies, 1975; Forbes et al., 1994). Arctic deltas provide critical nesting habitat for waterfowl and shorebirds. The largest Arctic deltas (e.g., Lena, Mackenzie, Yenisey, and Ob’) are at the mouths of northward-flowing major rivers with extensive drainage basins well to the south (Figure 1). They interrupt the coastal plain and extend seaward to varying degrees, depending on the configuration of the preexisting coast. Some, such as the Ob’, drain into large bays or estuaries (Whitehouse et al., 2007), whereas others, such as the Lena and the Coppermine, have built seaward (Aré and Reimnitz, 2000; Dredge, 2001). The Mackenzie Delta has partially infilled a glacial trough that extends seaward across the shelf. Smaller coastal plain deltas such as the Babbage are thin transgressive veneers of delta sediment on top of valley

Polar Coasts

floor deposits (Figure 14(c) and 27(a)) (Forbes, 1983; Forbes et al., 1994). Early work on the Colville River Delta (Figure 1) high­ lighted several aspects of high-latitude deltas, in particular the strong seasonal signal and the importance of the spring break-up flood, as well as the limited relief of channel-bank levees in a treeless setting (Walker, 1969, 1974, 1976). The Mackenzie Delta is by far the best-documented Arctic system (Figure 13), with work stretching back to the early 1960s (Mackay, 1963) and continuing to the present day (e.g., Marsh and Hey, 1989; Marsh and Ommaney, 1991; Hill, 1996; Taylor et al., 1996; Jenner and Hill, 1998; Marsh et al., 1999; Hill et al., 2001; Emmerton et al., 2007; Solomon et al., 2008; Burn and Kokelj, 2009; Goulding et al., 2009). The delta is a patchwork of major and minor channels wetlands (1614 km2), dry floodplain (1744 km2), 2 (6446 km ), and 49 046 lakes (3331 km2), giving a total area of 13 135 km2 (Emmerton et al., 2007). The axial length (north–south) is about 200 km and the width is typically 60–70 km, but expands to 120 km at the delta front. The lake concentration varies from <30% in the southern delta to 30–50% in the mid-delta to <15% north of the tree line (Mackay, 1963). Levee heights decrease seaward from 9.0 to <1.5 m above late-summer low water levels, with an abrupt drop in the vicinity of the tree line and the upper limit of storm-surge flooding (Lewis, 1988; Hill et al., 2001). Delta aggradation occurs by overbank flow during the spring flood, at times increased by ice jams in the upper delta, and sedi­ mentation in delta lakes mediated by depths of closure (Marsh and Hey, 1989; Marsh et al., 1999). Emmerton et al. (2007) estimated that floodwater storage on the floodplain and lakes is equivalent to about 47% of typical Mackenzie River discharge during the high-water break-up period. There is evidence that the Mackenzie Delta formerly extended nearly 40 km further seaward along much of its front (e.g., Taylor et al., 1996), but a wider front and continuing relative sea-level rise (in part through delta subsidence) may have tipped the balance to delta-front retreat some 4000 years ago (Hill et al., 2001; cf. Muto and Steel, 1992). Delta-front stability is related to wave action and thaw along the delta front and to the overall status and trends in delta surface elevation relative to sea level. This is a function of sea-level rise, delta subsidence, and vertical aggradation through overbank sedimentation. Despite the Mackenzie River being the largest source of sediment input to the Arctic Ocean (Rachold et al., 2000; Gordeev, 2006), most of the delta front continues to retreat at rates ranging from < 1.0 to > 20 m yr−1 (Solomon, 2005). Natural subsidence occurs through a combination of shallow compaction, deep compaction through expulsion (or extraction) of deep fluids (water or gas), lithospheric loading, any regional tectonic motion (including fault activation), and GIA. Near-surface processes are also important, including thaw con­ solidation with climate-induced deepening of the active layer (seasonal depth of thaw) and sedimentation contributing to delta plain aggradation. The compaction of Arctic delta sedi­ ments is restricted by ice bonding in permafrost, but may continue beneath lakes and channels with depths greater than the maximum penetration of winter freezing (typically 1–2 m). The occurrence of bottomfast ice in river mouth areas sets the stage for another distinctive high-latitude process, involving overflow by early spring discharge from the rivers. Because the

273

largest Arctic rivers drain areas far to the south in mid-latitudes, the spring flood is initiated ahead of ice break-up and drives progressive break-up northward over several weeks (Aré and Reimnitz, 2000; Reimnitz, 2000; Goulding et al., 2009). Rising under-ice pressure in the deltas leads to upwelling and over­ flow, initially by very clear water, spreading seaward over bottomfast and floating ice (Solomon et al., 2008). Even smal­ ler rivers such as the Colville, Sagavanirktok, and other North Slope Alaska rivers, and the Malcolm, Firth, Babbage, and Blow in the Yukon begin flowing while ice remains in their lower reaches (Walker, 1969, 1974; Forbes et al., 1994). Flood water from the Colville River spreads as much as 18 km offshore over the sea ice Hearon et al. (2009). Off the Mackenzie River, the ice overflow typically extends up to 30 km seaward from the delta front (Solomon et al., 2008). Similar river outflow over ice is documented in the Pechora Sea (Ogorodov et al., 2005). As overflow water begins to drain below the buoyant floating ice through tidal cracks or other orifices, the bottomfast ice remains bonded to the seabed. Vortex drainage develops down holes that form along cracks in the floating ice, eroding circular scour holes into the seabed (Reimnitz and Bruder, 1972; Reimnitz et al., 1974; Reimnitz and Kempema, 1983). These are most abundant just beyond the transition from bot­ tomfast to floating ice in depths of 1.4–5 m (Reimnitz et al., 1974). Strudel scour is now recognized as an active process with important implications for seabed infrastructure in the Prudhoe Bay field (Leidersdorf et al., 2006; Hearon et al., 2009) and the process has recently been confirmed off the Mackenzie Delta (Solomon et al., 2008). It is suspected, but not confirmed, to occur in other Arctic regions (Ogorodov et al., 2005). Forbes and Taylor (1994) summarized theoretical and experimental studies to quantify the asymptotic depth and radius of scour as a function of the hydrostatic head, the hole diameter, the depth of water beneath the ice, and a densimetric Froude number. The strudel depressions in Alaska are typically 2–6 m deep and up to 25 m in diameter (Reimnitz and Kempema, 1983). The Coppermine River enters Coronation Gulf at Kugluktuk, Nunavut, through a semicircular delta constructed under conditions of diminishing uplift and emergence (Dredge, 2001), although this area may have switched (or be on the point of switching) to a submergent trend (Forbes et al., 2004; James et al., 2010). Sandy, terraced, finger deltas draining unlithified Cretaceous to Tertiary formations on islands in the Sverdrup Basin record a full postglacial record of sediment delivery (Forbes et al., 1986; Forbes and Taylor, 1994). These too are in a region that appears to have changed to a submergent regime (Lajeunesse and Hanson, 2008), but they developed as highly distinctive landforms indicative of river-mouth sedimentation under forced regression with near-complete wave suppression due to persistent summer ice cover. Permafrost growth in the fan delta topsets at the noses of these deltas resulted in self-confinement as base level continued to fall and the rivers became incised within their own deposits. The Nastapoka River Delta in eastern Hudson Bay is a somewhat different case in an area of very rapid uplift. This delta is fed by fluvial incision into emerged deposits and the depositional facies are primarily subaqueous (Lavoie et al., 2002). Coarse-clastic proglacial and paraglacial fjord-head deltas and fjord-side fan deltas are common in many parts of the Arctic, where multiple terraces record the

274

Polar Coasts

repeated deposition of simple topset–foreset deltas at successively lower sea levels (e.g., Lønne and Nemec, 2004; see also Chapter 3.07).

3.10.4.4

Polar Coastal Marshes

Vegetated coastal wetlands are widespread along the circum-Arctic coast, though poorly developed in some places and absent from most polar desert shores. Polar coastal wet­ lands include salt marshes or brackish/freshwater marshes, inundated tundra (submerged by relative sea-level rise), back-barrier depressions and beach–ridge swales, and coastal and delta floodplains (Figure 27) (Jefferies, 1977; Bliss, 1993; Martini et al., 2009). On microtidal coasts such as the Beaufort Sea, most salt marshes are supratidal and inundated by moderate storm surges (Forbes et al., 1994; Hill and Solomon, 1999). Taylor (1981) reported vegetation zonation sensitive to elevation differences of a few centimeters, with the seaward limit of salt-tolerant and extremely hardy vegetation defined by the mean high water level (typically Puccinellia phryganodes). Rare extreme storm surges (>1.5 m) can cause salt burn, even in the freshwater-dominated Mackenzie Delta, if upwelling conditions ahead of a storm surge bring saltwater close to the coast: an event of this kind occurred in 1999 and caused widespread die-off of willow on the outer delta (S.V. Kokelj et al., personal communication).

Salt marshes are widely distributed along the Russian Arctic coast from the White Sea to Chukotka (Chernov and Matveyeva, 1997; Zöckler et al., 2011). Many Arctic regions have only a small diversity of coastal flora – for example, just 18 species in the Lena Delta area (Zöckler et al., 2011). There is some exchange of coastal species between the Arctic and the Pacific through the Bering Strait, including expansion of Arctic species south along the east side of Chukotka and northward spread of boreal species along the Alaska coast. Circumpolar species such as P. phryganodes and Carex subspathacea are wide­ spread along the Russian coast as well (Martini et al., 2009). The coasts of Hudson Bay and Foxe Basin, in a rapidly emergent region with predominantly low coastal relief, are bordered by very extensive coastal plains in the northeast and south. The west coast of southern Baffin Island is an extremely low-angle, lake-dotted, coastal plain, sloping very gently to vast tidal flats in southeastern Foxe Basin. Along the southern (Ontario) coast of Hudson Bay and western James Bay is another enormous area of emergent coastal plain with distinct shore-normal zonation in a region very close to the tree line (Martini et al., 1980, 2009). In the vicinity of Cape Henrietta Maria at the northwestern corner of James Bay, the postglacial marine limit is >400 km inland and well-defined emerged beach ridges extend more than 200 km from the present coast (Dredge and Cowan, 1989). Well-developed open-coast marshes in sub-Arctic western James Bay show a landward

(a)

(b)

(c)

(d)

Figure 27 Arctic coastal wetlands: (a) supratidal delta flats of the Babbage Delta, Yukon coastal plain, with numerous lakes and shallow ponds, driftwood-strewn palsa complex (‘Chaos Island’), and unvegetated tidal flats in foreground; (b) mixed sedge-willow wetland on the shore of Big Lake, outer Mackenzie Delta, in the Kendall Island Bird Sanctuary; (c) thin wetland habitat in swale between gravel beach ridges, Hall Beach, Foxe Basin, Nunavut; and (d) Puccinellia/Carex supratidal flat partially flooded by high spring tide, Cambridge Bay, Victoria Island, Nunavut. Photo source: DLF, 1976, 2010, 2007, 2009

Polar Coasts

zonation from tidal flats to freshwater marshes and eventually peat fens (Martini et al., 2009). In areas of well-developed beach ridges, thin marshes develop in the swales with peat fen developing inland. Further north, in a harsher climate, similar settings on the west side of Foxe Basin have extremely limited marsh development and little peat growth (Figure 27(c)). Dionne (1989) reviewed the range of frost and ice-related phenomena affecting salt marshes in mid- to high-latitudes. These include effects of permafrost development on emergent coasts (cf. Hansell et al., 1983), resulting in the development of a wide range of periglacial features such as frost mounds, mineral palsas, polygonal ice wedges, nonsorted circles, frost-heaved boulders, and thermokarst features (Allard and Seguin, 1987; Fournier et al., 1987; Allard et al., 1988; Dionne, 1989). Permafrost mounds and mineral palsas create relief of <1 m and 2–3 m, respectively, with horizontal dimen­ sions of several meters. The preponderance of supratidal marsh surfaces in microtidal regions relates to heave from the growth of segregated ice in the marsh substrate. Differential thaw of segregated ice can ensue due to ice scour, currents, saltwater intrusion, animal tracks, or other disturbance, and the resulting volume loss produces a honey­ comb microrelief of mounds and depressions (Figure 27(a); Dionne, 1989). Shallow ponds on polar marshes can also be formed by adfreezing to the bottom of grounded ice floes that are subsequently refloated, removing the patch of vegetation (Dionne, 1989; Martini et al., 2009).

3.10.5 Summary and Conclusions Distinguishing features of polar and subpolar coasts are extreme seasonality and the presence of various types of ice in the shore zone, including permafrost and ground ice in the littoral and nearshore substrate. Wave activity, though effective mainly dur­ ing the short summers, imposes a strong morphological signature on most sedimentary coasts, although some that are perennially ice bound show little evidence of wave action. Tidewater glaciers, grounded ice-sheet margins, and ice shelves form ice coasts, which cover the greater part of the Antarctic periphery and are common in some parts of the Arctic, but many ice shelves in both hemispheres are in sharp decline. Sea-ice cover expands and wanes on an annual cycle: the late summer minimum extent is stable or increasing in the Antarctic but declining rapidly in much of the Arctic, creating a longer open-water season, promoting increasing sea-surface temperatures and providing opportunities for more energetic storm-wave events. The evidence on the sensitivity of coastal erosion rates to these changes is inconsistent from region to region. Sea ice plays a variety of roles, as direct and indirect shore protection (inhibiting waves or defending against them), as a constructive force pushing sediment landward and creating a variety of distinctive landforms, and as an erosional force that can be destructive to coastal infrastructure. Cold mean annual temperatures in polar regions result in the widespread occurrence of permafrost and associated ground ice, which extend below sea level in some regions. Where the coast is dominated by sediments, such as on the Arctic coastal plain, this promotes enhanced rates of coastal

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erosion through combinations of thermal and mechanical pro­ cesses. Distinctive types of erosion include thermal niche undercutting, also aided by ice bonding of overlying sediment, failure of cantilevered blocks at polygonal ice wedges, active-layer (seasonal thaw) detachment failures, and RTF fail­ ures in sediments with massive ice or very high propotions of excess ice. These phenomena dominate the coastal landscape across a wide part of the north polar region forming the Arctic coastal plain. Large concentrations of lakes in much of this region, which is also subsiding and undergoing marine trans­ gression, promote the development of highly intricate coastlines formed by the erosional breaching and coalescence of lake basins and the growth of mobile spits and barriers across the mouths of the resulting embayments. Surface runoff is extremely limited in Antarctica but plays an important role in the Arctic. This has led to the development of innumerable small to medium deltas and a number of very large high-latitude deltas dominated by permafrost and the effect of river discharge into ice-covered seas. Polar and sub­ polar coastal wetlands and tidal flats also take a variety of distinctive forms, including a preponderance of high intertidal to supratidal marshes and extensive boulder-strewn tidal flats with distinctive features such as boulder pavements, garlands, and barricades. Moderate to high-relief rock coasts, including fjord-side cliffs, other cliffs with and without talus ramps, rock ramps, and some areas of low-relief skerries, are widespread through many parts of the Arctic and dominate the limited ice-free areas of Antarctica. Where glacial sediments or friable rock promotes the production of gravel, many rock-dominated coasts of mod­ erate relief with some summer open water have a veneer of beach ridges and may support the development of small spits, barriers, or cuspate forelands. The largest coastal depositional systems occur on the Arctic coastal plain or other areas of extensive sediment supply and predominantly on submergent coasts. Emergent coasts, result­ ing primarily from glacio-isostatic rebound, occur over large areas of the Arctic and most of Antarctica. In these regions, emergent relict coastal landforms (delta terraces, beach ridges, and shore platforms) lie well above the present sea level and beyond the reach of active shore processes. The Antarctic coast is composed of ice and rock cliffs or seaward-sloping ramps of ice and rock. Where sediment such as glacial till or rock scree is locally available, primarily along the Antarctic Peninsula and on sub-Antarctic islands, small beaches occur, but beaches are rare on a circumpolar scale. Meltwater streams are largely absent in the Antarctic and this restricts substantial beach development to the few areas where glacial outwash transport of sediment occurs, notably the sub-Antarctic islands.

Acknowledgments We thank A. Alsop, S. Emslie, D.E. Sugden, M. Usher, R.B. Taylor, and S.M. Solomon for permission to use their photo­ graphs. We are grateful to Bob Taylor and Nicole Couture for detailed and insightful reviews of an earlier draft. We thank Gavin Manson for assistance with the polar presentation of the Ice-5G model results and Hugues Lantuit for assistance with

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maps. We gratefully acknowledge colleagues, students, and others who have assisted in the field and the organizations that have supported our fieldwork. In the Antarctic, this includes the British Antarctic Survey, the Natural Environmental Research Council, the Carnegie Trust, the National Geographic, and the Royal Scottish Geographical Society. In Canada, it includes the Polar Continental Shelf Program, the Nunavut Research Institute, the Aurora Research Institute, the Canadian Coast Guard, ArcticNet and the National Centres of Excellence, the Government of Nunavut, and Natural Resources Canada. This is contribution no. 20100368 of the Earth Sciences Sector (Geological Survey of Canada), Natural Resources Canada.

References ACIA, 2005. Arctic Climate Impacts Assessment. Cambridge University Press, Cambridge, 1042 pp. Akagawa, M., 1964. On the drifting of pack-ice in the Pacific Ocean off Hokkaido (in Japanese with English abstract). Bulletin of the Hakodate Marine Observatory 11,50–65. Alestalo, J., Häikiö, J., 1976. Ice features and ice-thrust shore forms at Luodonselkä, Gulf of Bothnia, in winter 1972–73. Fennia 144, 1–24. Allard, M., Michaud, Y., Ruz, M.-H., Héquette, A., 1998. Ice foot, freeze–thaw of sediments, and platform erosion in a subarctic microtidal environment, Manitounuk Strait, northern Quebec, Canada. Canadian Journal of Earth Sciences 35 (9), 965–979. Allard, M., Seguin, M., 1987. Le pergélisol au Québec nordique: bilan et perspectives. Géographie physique et Quaternaire 41, 141–152. Allard, M., Seguin, M.K., Pelletier, Y., 1988. Shoreline permafrost in Kangiqsualujjuaq Bay, Ungava Bay, Québec. Proceedings of the 5th International Conference on Permafrost. Tapir, Trondheim, Norway, pp. 113–118. Anderson, J.B., 1991. The Antarctic continental shelf: results from marine geological and geophysical investigations. In: Tingey, R.J. (Ed.), The Geology of Antarctica. Clarendon Press, Oxford, pp. 285–334. Anderson, R.S., Wobus, C.W., Overeem, I., Clow, G.D., Urban, F.E., Stanton, T.P., 2009. Rapid coastal erosion on the Beaufort Sea coast: a triple whammy induced by climate change. Eos, Transactions American Geophysical Union 90 (52), Fall Meeting Supplement, Abstract U34B-01. Andrews, J.T., 1970. A Geomorphological Study of Post-glacial Uplift with Particular Reference to Arctic Canada. Institute of British Geographers, London, Special Publication 2, 156 pp. Andrews, J.T., 1989. Postglacial emergence and submergence. In: Fulton, R.J. (Ed.), Quaternary Geology of Canada and Greenland. Geology of Canada, no. 1, Geological Survey of Canada, Ottawa, Ch. 8 , pp.546–562 (also The Geology of North Ameriaca, Vol. K-1, Geological Society of America). Aré, F.E., 1980. Thermal abrasion of sea coasts. Nauka Publishing House, Moscow, 160 pp. (in Russian). Aré, F.E., 1988. Thermal abrasion of sea coasts. Polar Geography and Geology 12, 1–157. Aré, F.E., 1996. Dynamics of the littoral zone of Arctic seas (state of the art and goals). Polarforschung 64 (3), 123–131. Aré, F.E., Grigoriev, M.N., Hubberten, H.-W., Rachold, V., 2005. Using thermoterrace dimensions to calculate the coastal erosion rate. Geo-Marine Letters 25, 121–126. Aré, F.E., Reimnitz, E., 2000. An overview of the Lena River delta setting: geology, tectonics, geomorphology, and hydrology. Journal of Coastal Research 16 (3), 1083–1093. Aré, F.E., Reimnitz, E., Grigoriev, M., Hubberten, H.-W., Rachold, V., 2008. The influence of cryogenic processes on the erosional Arctic shoreface. Journal of Coastal Research 24 (1), 110–121. Atkinson, D.E., 2005. Observed storminess patterns and trends in the circum-Arctic coastal regime. Geo-Marine Letters 25, 98–109. Barber, D.G., Galley, R., Asplin, M.G., De Abreu, R., Warner, K.-A., Pućko, M., Gupta, M., Prinsenberg, S., Julien, S., 2009. Perennial pack ice in the southern Beaufort Sea was not as it appeared in the summer of 2009. Geophysical Research Letters 36, L24501. doi:10.1029/2009GL041434. Barnes, P.W., 1982. Marine ice-pushed boulder ridge, Beaufort Sea, Alaska. Arctic 35 (2), 312–316. Barnes, P.W., Kempema, E.W., Reimnitz, E., McCormick, M., Weber, W.S., Hayden, E.C., 1993. Beach profile modification and sediment transport by ice: an overlooked process on Lake Michigan. Journal of Coastal Research 9 (1), 65–86.

Barnes, P.W., Kempema, E.W., Reimnitz, E., McCormick, M., 1994. The influence of ice on southern Lake Michigan coastal erosion. Journal of Great Lakes Research 20, 179–195. Barnes, P.W., Rearic, D.M., Reimnitz, E., 1984. Ice gouging characteristics and processes. In: Barnes, P.W., Schell, D.M., Reimnitz, E. (Eds.), The Alaskan Beaufort Sea: ecosystems and environments. Academic Press, Orlando, pp. 185–212. Barnes, P.W., Reimnitz, E., 1988. Construction of an Arctic barrier island by alternating sea-ice pileup and overwash. In: Galloway, J.P., Hamilton, T.D. (Eds.), Geologic Studies in Alaska by the US Geological Survey during 1987. United State Geological Survey, Washington DC, Circular 1016, pp. 180–182. Bednarski, J., 1988. The geomorphology of glaciomarine sediments in a High Arctic fiord. Géographie physique et Quaternaire 42 (1), 65–74. Bélanger, S., Filion, L., 1991. Niveo-aeolian sand deposition in subarctic dunes, eastern coast of Hudson Bay, Quebec, Canada. Journal of Quaternary Science 6, 27–37. Bentley, M.J., Evans, D.J.A., Fogwill, C.J., Hansom, J.D., Sugden, D.E., Kubik, P.W., 2007. Glacial geomorphology and chronology of deglaciation, South Georgia, sub-Antarctic. Quaternary Science Reviews 26, 644–677. doi:10.1016/j.quascirev.2006.11.019. Berkman, P.A., Andrews, J.T., Björck, S., Colhoun, E.A., Emslie, S.D., Goodwin, I.D., Hall, B.L., Hart, C.P., Hirakawa, K., Igarashi, A., Ingólfsson, O., López-Martínez, J., Lyons, W.B., Mabin, M.C.G., Quilty, P.G., Taviani, M., Yoshida, Y., 1998. Circum-Antarctic coastal environmental shifts during the late Quaternary reflected by emerged marine deposits. Antarctic Science 10, 345–362. Bernatchez, P., Dubois, J.-M.M., 2004. Bilan des connaissances de la dynamique de l’érosion des côtes du Québec maritime laurentian. Géographie physique et Quaternaire 58 (1), 45–71. Bindoff, N.L., Willebrand, J., Artale, V., Cazenave, A., Gregory, J.M., Gulev, S., Hanawa, K., le Quéré, C., Levitus, S., Nojiri, Y., Shum, C.K., Talley, L.D., Unnikrishnan, A.S., 2007. Observations: oceanic climate change and sea level. In: Solomon, S., Qin, D., Manning, M., Marquis, M., Averyt, K., Tignor, M.M.B., Miller, H.L., Jr. (Eds.), Climate Change 2007: The Physical Science Basis, Contribution of Working Group I to the Fourth Assessment Report of the Intergovernmental Panel on Climate Change. Cambridge University Press, Cambridge, pp. 385–432. Bird, E.C.F., 2003. Antarctica. In: Bird, E.C.F. (Ed.), The Worlds Coasts: Online. Springer, Berlin, Section 24.1, pp. 1697–1706. Bird, J.B., 1954. Postglacial marine submergence in central Arctic Canada. Geological Society of America Bulletin 65 (5), 457–464. Bird, J.B., 1967. The Physiography of Arctic Canada. The Johns Hopkins Press, Baltimore, 336 pp. Bird, J.B., 1985. Arctic Canada. In: Bird, C.F., Schwartz, M.L. (Eds.), The World’s Coastline. Van Nostrand Reinhold, New York, pp. 241–251. Birnie, R.V., Gordon, J.E., 1980. Drainage systems associated with snow melt, South Shetland Islands, Antarctica. Geografiska Annaler 62A, 57–62. Blake, W., Jr., 1970. Studies of glacial history in Arctic Canada. I. Pumice, radiocarbon dates, and differential postglacial uplift in the eastern Queen Elizabeth Islands. Canadian Journal of Earth Sciences 7, 634–664. Blasco, S., 1995. Origin and Engineering Implications of Deep Ice-Bearing Permafrost, Canadian Beaufort shelf. Proceedings, Oil and Gas Forum ’95. Geological Survey of Canada, Ottawa, Open File 3058, pp. 159–161. Bliss, L.C., 1993. Arctic coastal ecosystems. In: van der Maarel, E. (Ed.), Dry Coastal Ecosystems, Polar Regions and Europe. Ecosystems of the World 2A. Elsevier, Amsterdam, pp. 7–22. Bockheim, J.G., 1995. Permafrost distribution in the Southern Circumpolar Region and its relation to the environment: a review and recommendations for further research. Permafrost and Periglacial Processes 6, 27–45. Bondarev, V.N., Rokos, S.I., Tarasov, G.A., Kostin, D.A., Dlugach, A.G., Polyakova, N.A., 2005. Cryogenic processes and phenomena in the upper sediment layer of the Pechora Sea. In: Bauch, H.A., Pavlidis, Yu.A., Polyakova, Ye.I., Matishov, G.G., Koç, N. (Eds.), Pechora Sea Environments: Past, Present, and Future. Berichte zur Polar- und Meeresforschung 501. pp. 141–153. Alfred Wegener Institute, Bremerhaven. Bourke, M.C., Ewing, R.C., Finnegan, D., McGowan, H.A., 2009. Sand dune movement in the Victoria Valley, Antarctica. Geomorphology 109 (3–4), 148–160. doi:10.1016/ j.geomorph.2009.02.028. Brigham-Grette, J., Hopkins, D., 1995. Emergent marine record and paleoclimate of the last interglaciation along the northwest Alaska coast. Quaternary Research 43, 159–173. Briner, J.P., Overeem, I., Miller, G., Finkel, R., 2006. The deglaciation of Clyde Inlet, northeastern Baffin Island, Arctic Canada. Journal of Quaternary Science 22 (3), 223–232. Broström, G., Christensen, K., 2008. Waves in sea ice. Norwegian Meteorological Institute, Met.no Report no. 5, 63 pp. Brown, J., Ferrians, O.J., Jr., Heginbottom, J.A., Melnikov, E.S., 1998. Circum-Arctic map of permafrost and ground-ice conditions. In: Parsons, M., Zhang, T. (Eds.),

Polar Coasts

Circumpolar Active-Layer Permafrost System, Version 2.0. National Snow and Ice Data Center, Boulder (CD-ROM). Brückner, H., Schellmann, G., van der Borg, K., 2002. Uplifted beach ridges in northern Spitsbergen as indicators for glacio-isostasy and palaeo-oceanography. Zeitschrift für Geomorphologie 46 (3), 309–336. Bryan, M., Bell, T., Smith, I.R., Forbes, D., 2006. Sill evolution in marine inundated basins, Sachs Harbour, Banks Island, NWT. Proceedings, ArcticNet Annual Science Meeting 2006, Victoria, Québec, pp. 74–75. http://www.arcticnet.ulaval.ca/pdf/ Programme_ASM2006.pdf. Burn, C.R., Kokelj, S.V., 2009. The environment and permafrost of the Mackenzie Delta area. Permafrost and Periglacial Processes 20 (2), 83–105. Butler, E.R.T., 1999. Process environments on modern and raised beaches in McMurdo Sound, Antarctica. Marine Geology 162, 105–120. Byrne, M.-L., Dionne, J.-C., 2002. Typical aspects of cold regions shorelines. In: Hewitt, K., Byrne, M.-L., English, M., Young, G. (Eds.), Landform Assemblages and Transformations in Cold Regions. Kluwer, Dordrecht, pp. 141–158. Carson, C.E., Hussey, K.M., 1962. The oriented lakes of Arctic Alaska. Journal of Geology 70, 417–439. Cavalieri, D.J., Parkinson, C.L., 2008. Antarctic sea ice variability and trends, 1979–2006. Journal of Geophysical Research 113, C07004. doi:10.1029/ 2007JC004564. Cavalieri, D.J., Parkinson, C.L., Vinnikov, K.Y., 2003. 30-year satellite record reveals contrasting Arctic and Antarctic decadal sea ice variability. Geophyiscal Research Letters 30 (18), 1970. doi:10.1029/2003GL018031. CAVM, 2003. Circumpolar Arctic Vegetation Map. Conservation of Arctic Flora and Fauna (CAFF), Map No. 1, scale 1: 7 500 000. US Fish and Wildlife Service, Anchorage, Alaska (http://www.geobotany.uaf.edu/cavm/). Chernov, Y.I., Matveyeva, N.V., 1997. Arctic ecosystems in Russia. In: Chapin, F.S., III, Körner, C. (Eds.), Polar and Alpine Tundra. Ecosystems of the World 3. Elsevier, Amsterdam, pp. 361–507. Church, M., 1974. Hydrology and permafrost with reference to northern North America. In: Demers, J. (Ed.), Proceedings of Workshop Seminar on Permafrost Hydrology. Canadian National Committee for the International Hydrological Decade, Ottawa, pp.7–20. Clapperton, C.M., Sugden, D.E., 1982. Late Quaternary glacial history of George VI sound area, West Antarctica. Quaternary Research 18, 243–267. Clapperton, C.M., Sugden, D.E., Birnie, R.V., Hansom, J.D., Thom, G., 1978. Glacier fluctuations in South Georgia and comparison with other island groups in the Scotia Sea. In: Van Zinderen Bakker, E.M., (Ed.), Antarctic Glacial History and World Palaeoenvironments. A.A. Balkema, Rotterdam, pp. 95–104. Clark, P.U., Dyke, A.S., Shakun, J.D., Carlson, A.E., Clark, J., Wohlfarth, B., Mitrovica, J.X., Hostetler, S.W., McCabe, A.M., 2009. The Last Glacial Maximum. Science 325, 710–714. Comiso, J.C., Parkinson, C.L., Gersten, R., Stock, L., 2008. Accelerated decline in the Arctic sea ice cover. Geophysical Research Letters 35, L01703. doi:10.1029/ 2007GL031972. Conlan, K.E., Kvitek, R.G., 2005. Recolonization of soft-sediment ice scours on an exposed Arctic coast. Marine Ecology Progress Series 286, 21–42. Cook, A.J., Fox, A.J., Vaughan, D.G., Ferrigno, J.G., 2005. Retreating glacier fronts on the Antarctic Peninsula over the past half-century. Science 308, 541–544. Cook, A.J., Vaughan, D.G., 2009. Overview of aerial changes of the ice shelves on the Antarctic Peninsula over the past 50 years. The Cryosphere Discussions 3, 579–630. wwww.the-cryosphere-discuss.net/3/579/2009/ (accessed February 2011). Craig, P.C., Griffiths, W.B., Johnson, S.R., Schell, D.M., 1984. Trophic dynamics in an Arctic lagoon. In: Barnes, P.W., Schell, D.M., Reimnitz, E. (Eds.), The Alaskan Beaufort Sea: Ecosystems and Environments. Academic Press, Orlando, pp. 347–380. Curran, M.A.J., van Ommen, T.D., Morgan, V.I., Phillips, K.L., Palmer, A.S., 2003. Ice core evidence for Antarctic sea ice decline since the 1950s. Science 302, 1203–1206. Dale, J.E., Leech, S., McCann, S.B., Samuelson, G., 2002. Sedimentary characteristics, biological zonation and physical processes of the tidal flats of Iqaluit, Nunavut. In: Hewitt, K., Byrne, M.-L., English, M., Young, G. (Eds.), Landform Assemblages and Transformations in Cold Regions. Kluwer, Dordrecht, pp. 205–234. Dallimore, S.R., 1991. Geological, Geotechnical and Geophysical Studies along an Onshore–Offshore Transect of the Beaufort Shelf. Geological Survey of Canada, Ottawa, Open File 2408, 325 pp. Dallimore, S.R., Collett, T.S., 1995. Intrapermafrost gas hydrates from a deep core hole in the Mackenzie Delta, Northwest Territories, Canada. Geology 23, 527–530. Dallimore, S.R., Kurfurst, P.J., Hunter, J.M., 1988. Geotechnical and geothermal conditions of nearshore sediments, southern Beaufort Sea, Northwest Territories, Canada. Proceedings of the 5th International Conference on Permafrost. Tapir, Trondheim, Norway, pp. 127–131. Dallimore, S.R., Taylor, A.E., 1994. Permafrost conditions along an onshore–offshore transect of the Canadian Beaufort Shelf. Proceedings of the 6th International

277

Conference on Permafrost, Beijing, China. South China University Press, Wushan, Guangzhou, pp. 125–130. Dallimore, S.R., Wolfe, S.A., Solomon, S.M., 1996. Influence of ground ice and permafrost on coastal evolution, Richards Island, Beaufort Sea coast, NWT. Canadian Journal of Earth Sciences 33, 664–675. Davies, K.F., 1975. Mackenzie River Input to the Beaufort Sea. Environment Canada, Victoria, BC. Beaufort Sea Project, Technical Report 15, 22 pp. Dayton, P.K., Robilliard, G.A., Devries, A.L., 1969. Anchor ice formation in McMurdo Sound, Antarctica, and its biological effects. Science 17, 273–274. Dietrich, R., Rülke, A., Ihde, J., Lindner, K., Miller, H., Niemeier, W., Schenke, H.-W., Seeber, G., 2004. Plate kinematics and deformation status of the Antarctic Peninsula based on GPS. Global and Planetary Change 42, 313–321. Dionne, J.-C., 1978. Le glaciel en Jamésie et en Hudsonie, Québec subarctique. Géographie physique et Quaternaire 32, 3–70. Dionne, J.-C., 1981a. Le déplacement de méga-blocs par les glaces sur les rivages du Saint-Laurent. Proceedings, Workshop on Ice Action on Shores, Rimouski. National Research Council Canada, Ottawa, pp. 53–80. Dionne, J.-C., 1981b. A boulder-strewn tidal flat, north shore of the Gulf of St. Lawrence. Géographie physique et Quaternaire 35, 261–268. Dionne, J.-C., 1984. An estimate of ice-drifted sediments based on the mud content of the ice cover at Montmigny, middle St. Lawrence Estuary. Marine Geology 57, 149–166. Dionne, J.-C., 1985. Formes, figures et faciès sédimentaires glaciels des estrans vaseux des régions froides. Palaeogeography, Palaeoclimatology, Palaeoecology 51, 415–451. Dionne, J.-C., 1988. Ploughing boulders along shorelines, with particular reference to the St. Lawrence estuary. Geomorphology 1, 297–308. Dionne, J.-C., 1989. The role of ice and frost in tidal marsh development – a review with particular reference to Québec, Canada. Essener Geographische Arbeiten 18, 171–210. Dionne, J.-C., 1992. Ice-push features. The Canadian Geographer 36, 86–91. Donnellan, A., Luyendyk, B.P., 2004. GPS evidence for a coherent Antarctic plate and for postglacial rebound in Marie Byrd Land. Global and Planetary Change 42, 305–311. Dozier, J., Marsh, B.D., Marsh, W.M., 1976. Ice cusp formation on Lake Superior icefoots. Revue de Géographie de Montréal 30, 161–179. Drake, J.J., McCann, S.B., 1982. The movement of isolated boulders on tidal flats by ice floes. Canadian Journal of Earth Sciences 19, 748–754. Dredge, L.A., 2001. Where the River Meets the Sea: Geology and Landforms of the Lower Coppermine River Valley and Kugluktuk, Nunavut. Geological Survey of Canada, Ottawa, Miscellaneous Report 69, 76 pp. Dredge, L.A., Cowan, W.R., 1989. Quaternary geology of the southwestern Canadian Shield. In: Fulton, R.J. (Ed.), Quaternary Geology of Canada and Greenland. Geology of Canada, no. 1, Geological Survey of Canada, Ottawa, Ch. 3, pp.214–235 (also The Geology of North Ameriaca, Vol. K-1, Geological Society of America). Drewry, D.J., 1983. The surface of the Antarctic ice sheet: sheet 2. In: Drewry, D.J. (Ed.), Antarctic Glaciological and Geophysical Portfolio. Scott Polar Research Institute, Cambridge. Drewry, D.J., 1991. The response of the Antarctic ice sheet to climatic change. In: Harris, C.M., Stonehouse, B. (Eds.), Antarctica and Global Climatic Change. Belhaven Press, London, pp. 90–106. Drewry, D.J., Jordan, S.R., Jankowski, E.J., 1982. Measured properties of the Antarctic Ice Sheet surface configuration, ice thickness, volume and bedrock characteristics. Annals of Glaciology 3, 83–91. Drozdov, D.S., Rivkin, F.M., Rachold, V., Ananjeva-Malkova, G.V., Ivanova, N.V., Chehina, I.V., Koreisha, M.M., Korostelev, Yu.V., Melnikov, E.S., 2005. Electronic atlas of the Russian Arctic coastal zone. Geo-Marine Letters 25 (2), 81–88. Dudeney, J.R., 1987. The Antarctic atmosphere. In: Walton, D.W.H. (Ed.), Antarctic Science. Cambridge University Press, Cambridge, pp. 193–149. Dyke, A.S., 1979. Glacial and sea-level history of southwestern Cumberland Peninsula, Baffin Island, NWT, Canada. Arctic and Alpine Research 11 (2), 179–202. Dyke, A.S., Dredge, L.A., 1989. Quaternary geology of the northwestern Canadian Shield. In: Fulton, R.J. (Ed.), Quaternary Geology of Canada and Greenland. Geology of Canada, no. 1, Geological Survey of Canada, Ottawa, Ch. 3, pp.189–214 (also The Geology of North Ameriaca, Vol. K-1, Geological Society of America). Dyke, A.S., England, J., Reimnitz, E., Jetté, H., 1997. Changes in driftwood delivery to the Canadian Arctic Archipelago: the hypothesis of postglacial oscillations of the transpolar drift. Arctic 50 (1), 1–16. Dyke, L.D., 1991. Temperature changes and thaw of permafrost adjacent to Richards Island, Mackenzie Delta, NWT. Canadian Journal of Earth Sciences 28, 1834–1842. Emmerton, C.A., Lesack, L.F.W., Marsh, P., 2007. Lake abundance, potential water storage, and habitat distribution in the Mackenzie River delta, western Canadian Arctic. Water Resources Research 43, W05419. doi:10.1029/2006WR005139. Eisenman, I., Wettlaufer, J.S., 2009. Nonlinear threshold behavior during the loss of Arctic sea ice. Proceedings National Academy of Sciences 106, 28–32. Etzelmüller, B., Ødegård, R.S., Sollid, J.L., 2003. The spatial distribution of coast types on Svalbard. Berichte zur Polar- und Meeresforschung 443, 33–40.

278

Polar Coasts

Evans, D.J.A., Rea, B.R., 2005. Late Weichselian deglaciation and sea level history of St. Jonsfjorden, Spitzbergen: a contibution to ice sheet reconstruction. Scottish Geographical Journal 121, 175–202. Evenson, E.B., Cohn, B.P., 1979. The ice-foot complex: its morphology, formation and role in sediment transport and shoreline protection. Zeitschrift für Geomorphologie 23, 58–75. Fetterer, F., Knowles, K., Meier, W., Savoie, M., 2002 (updated 2009). Sea Ice Index. National Snow and Ice Data Center, Boulder, Colorado. Digital media. http://nsidc. org/data/seaice_index/archives/index.html (accessed February 2011). Feyling-Hanssen, R.W., 1954. Brief account of the ice-foot. Norsk Geografisk Tidsskrift 14, 45–52. Fletcher, C.H., Fairbridge, R.W., Møller, J.J., Long, A.J., 1993. Emergence of the Varanger Peninsula, Arctic Norway, and climate changes since deglaciation. The Holocene 3 (2), 116–127. Forbes, D.L., 1979. Bottomfast ice in northern rivers: hydraulic effects and hydrometric implications. Proceedings, Canadian Hydrology Symposium 1979, Cold Climate Hydrology, Vancouver. National Research Council of Canada, Ottawa, pp. 177-184. Forbes, D.L., 1980. Late Quaternary sea levels in the southern Beaufort Sea. Geological Survey of Canada, Ottawa, Paper 80-1B, 75–87. Forbes, D.L., 1983. Morphology and sedimentology of a sinuous gravel-bed channel system: lower Babbage River, Yukon coastal plain. In: Collinson, J.D., Lewin, J. (Ed.), Modern and Ancient Fluvial Systems. International Association of Sedimentologists, Special Publication 6, pp. 195–206. Forbes, D.L., 1997. Coastal Erosion and Nearshore Profile Variability in the Southern Beaufort Sea, Ivvavik National Park, Yukon Territory. Geological Survey of Canada, Ottawa, Open File 3531, 28 pp. and appendices. Forbes, D.L., 2004. Ice-bonded sediments and massive ground ice in a transgressive barrier-lagoon and delta complex, Yukon coast of Beaufort Sea, western Arctic Canada. Eos, Transactions American Geophysical Union 85 (47), Fall Meeting Supplement, Abstract C13A-0267. Forbes, D.L., 2005. Coastal erosion. In: Nuttall, M. (Ed.), Arctic Encyclopedia. Routledge, New York, pp. 391–393. Forbes, D.L. (Ed.), 2011. State of the Arctic Coast 2010 – Scientific Review and Outlook. International Arctic Science Committee, Land-Ocean Interactions in the Coastal Zone, International Permafrost Association, Arctic Monitoring and Assessment Program, International Permafrost Association. LOICZ International Project Office, Geesthacht, Germany, 168 pp. Forbes, D.L., Craymer, M., Manson, G.K., Solomon, S.M., 2004. Defining limits of submergence and potential for rapid coastal change in the Canadian Arctic. Berichte zur Polar- und Meeresforschung 482, 196–202. Forbes, D.L., Solomon, S.M., Hamilton, T.S., 1994. Morphology and sedimentary processes of microtidal embayments, Beaufort Sea coast, western Arctic Canada. In: Viggósson, G. (Ed.), Proceedings, Hornafjörður International Coastal Symposium, Höfn. Icelandic Harbour Authority, Kópavogur, pp. 363–372. Forbes, D.L., Taylor, R.B., 1994. Ice in the shore zone and the geomorphology of cold coasts. Progress in Physical Geography 18, 59–89. Forbes, D.L., Taylor, R.B., Frobel, D., 1986. Coastal Studies in the Western Arctic Archipelago (Melville, Mackenzie King, Lougheed and nearby islands). Geological Survey of Canada, Ottawa, Open File 1409, 29 pp. Forman, S.L., Mann, D.H., Miller, G.H., 1987. Late Weichselian and Holocene relative sea-level history of Bröggerhalvöya, Spitsbergen. Quaternary Research 27 (1), 41–50. Fournier, A., Allard, M., Seguin, M., 1987. Typologie morpho-génétique des marelles du marais littoral de la baie de Kangiqsualujjuaq, estuaire du George, Québec nordique. Géographie physique et Quaternaire 41, 47–64. Gardner, N., Hall, B., Wehmiller, J., 2006. Pre-Holocene raised beaches at Cape Ross, Southern Victoria Land, Antarctica. Marine Geology 229 (3–4), 273–284. doi:10.1016/j.margeo.2006.01.006. Gilbert, R., Aitken, A.E., 1981. The role of sea ice in biophysical processes on intertidal flats at Pangnirtung (Baffin Island), NWT. Proceedings, Workshop on Ice Action on Shores, Rimouski. National Research Council Canada, Ottawa, pp. 89–103. Gloerson, P., Campbell, W.J., 1988. Variations in the Arctic, Antarctic and global sea ice covers during 1978–1987 as observed with the Nimbus 7 Scanning Multichannel Microwave Radiometer. Journal of Geophysical Research 93, 10666–10674. Gloerson, P., Campbell, W.J., Cavalieri, D.J., Comiso, J.C., Parkinson, C.L., Zwally, H.J., 1992. Arctic and Antarctic Sea Ice, 1978–1987. Satellite passive-microwave observations and analysis. NASA SP-511, Scientific and Technical Information Program, Washington, DC. Golovin, P., Dmitrenko, I., Kassens, H., Hölemann, J.A., 1999. Frazil ice formation during the spring flood and its role in transport of sediments to the ice cover. In: Kassens, H., Bauch, H.A., Dmitrenko, I., Eicken, H., Hubberten, H.-W., Melles, M., Thiede, J., Timokhov, L. (Eds.), Land–Ocean Systems in the Siberian Arctic: Dynamics and History. Springer, Berlin, pp. 125–140.

Goodwin, I.D., 1993. Holocene deglaciation, sea-level change, and the emergence of the Windmill Islands, Budd coast, Antarctica. Quaternary Research 40 (1), 55–69. Gordeev, V.V., 2006. Fluvial sediment flux to the Arctic Ocean. Geomorphology 80, 94–104. Gordon, D.C., Jr., Desplanque, C., 1981. Ice dynamics in the Chignecto Bay region of the Bay of Fundy. Proceedings, Workshop on Ice Action on Shores. National Research Council Canada, Ottawa, pp. 35–52. Gordon, J.E., Hansom, J.D., 1986. Beach forms and changes associated with retreating glacier ice, South Georgia. Geografiska Annaler 68A, 15–24. Goulding, H.L., Prowse, T.D., Beltaos, S., 2009. Spatial and temporal patterns of break-up and ice-jam flooding in the Mackenzie Delta, NWT. Hydrological Processes 23 (18), 2654–2670. Grass, J.D., 1984. Ice scour and ice ridging studies in Lake Erie. Proceedings of the 7th International Symposium on Ice. International Association for Hydraulic Research, Hamburg, pp. 33–43. Greene, H.G., 1970. Microrelief of an Arctic beach. Journal of Sedimentary Petrology 41 (1), 419–427. Gregory, M.R., Kirk, R.M., Mabin, M.C.G., 1984. Shore types of Victoria Land, Ross Dependency, Antarctica. New Zealand Antarctic Record 5(3), 22–40. Grosswald, M.G., Hughes, T.J., Lasca, N.P., 1999. Oriented lake-and-ridge assemblages of the Arctic coastal plains: glacial landforms modified by thermokarst and solifluction. Polar Record 35, 215–230. Gualtieri, L., Vartanyan, S., Brigham-Grette, J., Anderson, P.M., 2003. Pleistocene raised marine deposits on Wrangel Island, northeast Siberia and implications for the presence of an East Siberian ice sheet. Quaternary Research 59 (3), 399–410. Häggblom, A., 1982. Driftwood in Svalbard as an indicator of sea ice conditions. Geografiska Annaler 64A, 81–94. Hall, B.L., Baroni, C., Denton, G.H., 2004. Holocene relative sea-level history of the southern Victoria Land coast, Antarctica. Global and Planetary Change 42, 241–263. Hall, B.L., Denton, G.H., 2000. Extent and chronology of the Ross Sea ice sheet and the Wilson Piedmont Glacier along the Scott coast at and since the last glacial maximum. Geografiska Annaler 82A, 337–363. Hamilton, G.S., Spikes, V.B., 2004. Evaluating a satellite altimeter-derived digital elevation model of Antarctica using precision kinematic GPS profiling. Global and Planetary Change 42, 17–30. Hansell, R.I.C., Scott, P.A., Staniforth, R., Svoboda, J., 1983. Permafrost development in the intertidal zone at Churchill, Manitoba: a possible mechanism for accelerated beach lift. Arctic 36 (2), 198–203. Hansom, J.D., 1981. Storm surging in South Georgia. British Antarctic Survey Bulletin 53, 141–146. Hansom, J.D., 1983a. Shore-platform development in the South Shetland Islands, Antarctica. Marine Geology 53 (3), 211–229. Hansom, J.D., 1983b. Ice-formed intertidal boulder pavements in the sub-Antarctic. Journal of Sedimentary Petrology 53, 135–145. Hansom, J.D., 1986. Intertidal forms produced by floating ice in Vestfirðir, Iceland. Marine Geology 71, 289–298. Hansom, J.D., 2005a. Atlantic Ocean islands, coastal geomorphology. In: Schwartz, M.L. (Ed.), Encyclopedia of Coastal Science. Springer, Berlin, pp. 88–95. Hansom, J.D., 2005b. Boulder pavements. In: Schwartz, M.L. (Ed.), Encyclopedia of Coastal Science. Springer, Berlin, pp. 208–210. Hansom, J.D., 2010. Other Atlantic Islands. In: Bird, E.C.F. (Ed.), Encyclopedia of World’s Coastal Landforms. Springer, Berlin, 1600 pp. Hansom, J.D., Gordon, J.E., 1998. Antarctic Environments and Resources: A Geographical Perspective. Addison Wesley Longman, Harlow, 402 pp. Hansom, J.D., Kirk, R.M., 1989. Ice in the intertidal zone: examples from Antarctica. Essener Geographische Arbeiten 18, 211–236. Harper, J.R., 1978. Coastal erosion rates along the Chukchi Sea coast near Barrow, Alaska. Arctic 31 (4), 428–433. Harper, J.R., 1990. Morphology of the Canadian Beaufort Sea coast. Marine Geology 91,75–91. Harrowfield, D.L., 2006. Analysis of timber weathering and wind velocity at Cape Adare, with comments on other historic sites in Antarctica. Polar Record 42 (223), 291–307. Harry, S.A., French, H.M., 1983. The orientation and evolution of thaw lakes, southwest Banks Island, Canadian Arctic. Proceedings, 4th International Conference on Permafrost. National Academies Press, Washington, DC, pp. 456–461. Hartwell, A.D., 1973. Classification and relief characteristics of northern Alaska’s coastal zone. Arctic 26, 244–252. Hearon, G.D., Dickins, D., Ambrosius, K., Morris, K., 2009. Mapping Sea Ice Overflood Using Remote Sensing: Smith Bay to Camden Bay. Report to Alaska OCS Region, Minerals Management Service, US Department of Interior. DF Dickens Associates, Coastal Frontiers Corporation, Aerometric, and Geophysical Institute, University of Alaska, xii+110 pp. Héquette, A., 1992. Morphosedimentological dynamics and coastal evolution in the Kongsfjorden area, Spitsbergen. Polar Geography 16 (4), 321–328.

Polar Coasts

Héquette, A., Barnes, P.W., 1990. Coastal retreat and shoreface profile variations in the Canadian Beaufort Sea. Marine Geology 91, 113–132. Héquette, A., DesRosiers, M., Barnes, P.W., 1995a. Sea ice scouring on the inner shelf of the southeastern Canadian Beaufort Sea. Marine Geology 128, 201–219. Héquette, A., Hill, P.R., 1993. Storm-generated currents and offshore sediment transport on a sandy shoreface, Tibjak Beach, Canadian Beaufort Sea. Marine Geology 113, 283–304. Héquette, A., Hill, P.R., 1995. Response of the seabed to storm-generated combined flows on a sandy Arctic shoreface, Canadian Beaufort Sea. Journal of Sedimentary Research 65, 461–471. Héquette, A., Ruz, M.-H., 1986. Migration de cordons littoraux par processus de débordements de tempête dans le cadre d’une transgression marine, Kvadehuk, péninsule de Brögger, Spitsberg. Géographie physique et Quaternaire 40 (2), 197– 206. Héquette, A., Ruz, M.-H., 1990. Sédimentation littorale en bordure de plaines d’épandage fluvioglaciaire au Spitsberg nord-occidental. Géographie physique et Quaternaire 44, 77–88. Héquette, A., Ruz, M.-H., 1991. Spit and barrier island migration in the southeastern Canadian Beaufort Sea. Journal of Coastal Research 7 (3), 677–698. Héquette, A., DesRosiers, M., Hill, P.R., Forbes, D.L., 2001. The influence of coastal morphology on shoreface sediment transport under storm-combined flows, Canadian Beaufort Sea. Journal of Coastal Research 17 (3), 507–516. Héquette, A., Ruz, M.-H., Hill, P.R., 1995b. The effects of the Holocene sea level rise on the evolution of the southeastern coast of the Canadian Beaufort Sea. Journal of Coastal Research 11 (2), 494–507. Hill, P.R., 1990. Coastal geology of the King Point area, Yukon Territory, Canada. Marine Geology 91, 93–111. Hill, P.R., 1996. Late Quaternary sequence stratigraphy of the Mackenzie Delta. Canadian Journal of Earth Sciences 33, 1064–1074. Hill, P.R., Barnes, P.W., Héquette, A., Ruz, M.-H., 1995. Arctic coastal plain shorelines. In: Carter, R.W.G., Woodroffe, C.D. (Eds.), Coastal Evolution: Late Quaternary Shoreline Morphodynamics. Cambridge University Press, Cambridge, pp. 341–372. Hill, P.R., Lewis, C.P., Desmarais, S., Kauppaymuthoo, V., Rais, H., 2001. The Mackenzie Delta: sedimentary processes and facies of a high-latitude, fine-grained delta. Sedimentology 48, 1047–1078. Hill, P.R., Solomon, S.M., 1999. Geomorphologic and sedimentary evolution of a transgressive thermokarst coast, Mackenzie Delta region, Canadian Beaufort Sea. Journal of Coastal Research 15 (4), 1011–1029. Hinkel, K.M., Frohn, R.C., Nelson, F.E., Eisner, W.R., Beck, R.A., 2005. Morphometric and spatial analysis of thaw lakes and drained lake basins in the western Arctic coastal plain, Alaska. Permafrost and Periglacial Processes 16 (4), 327–341. Hinz, K., Delisle, G., Block, M., 1998. Seismic evidence for the depth extent of permafrost in shelf sediments of the Laptev Sea, Russian Arctic. Proceedings, 7th International Conference on Permafrost, Yellowknife. Collection Nordicana, Québec, no. 55, pp. 453–457. Hivon, E.G., Sego, D.C., 1993. Distribution of saline permafrost in the Northwest Territories, Canada. Canadian Geotechnical Journal 30 (3), 506–514. Hodgson, D.A., 1989. Introduction (Quaternary geology of the Queen Elizabeth Islands). In: Fulton, R.J. (Ed.), Quaternary Geology of Canada and Greenland. Geology of Canada, no. 1, Geological Survey of Canada, Ottawa, Ch. 6, pp. 443–448 (also The Geology of North Ameriaca, Vol. K-1, Geological Society of America). Hodgson, D.A., Taylor, R.B., Fyles, J.G., 1994. Late Quaternary sea level changes on Brock and Prince Patrick Islands, western Canadian Arctic Archipelago. Géographie physique et Quaternaire 48 (1), 69–84. Holmes, M.L., Creager, J.S., 1974. Holocene history of the Laptev Sea continental shelf. In: Herman, Y. (Ed.), Marine Geology and Oceanography of the Arctic Seas. Springer, Berlin, pp. 211–229. Hoque, Md.A., Pollard, W.H., 2009. Arctic coastal retreat through block failure. Canadian Geotechnical Journal 46, 1103–1115. Hubberten, H.-W., Romanovskii, N.N., 2003. The main features of permafrost in the Laptev Sea region, Russia – a review. Proceedings, 8th International Conference on Permafrost, Zurich, Switzerland. pp. 431–436. A.A. Balkema, Rotterdam. Hudson, R.D., Pilkington, G.R., Metge, M., 1981. Extreme ice features along the NW edge of the Canadian Archipelago. Proceedings, Workshop on Ice Action on Shores, Rimouski. National Research Council Canada, Ottawa, pp. 15–34. Hume, J.D., Schalk, M., 1964. The effects of ice-push on Arctic beaches. American Journal of Science 262, 267–273. Hume, J.D., Schalk, M., 1967. Shoreline processes near Barrow, Alaska: a comparison of the normal and the catasrophic. Arctic 20, 86–103. Hume, J.D., Schalk, M., 1976. The effects of ice on the beach and nearshore, Pt Barrow, Arctic Alaska. Revue de Géographie de Montréal 30, 105–114. Hunter, J.A., Judge, A.S., MacAulay, H.A., Good, R.L., Gagné, R.M., Burns, R.A., 1976. Permafrost and sub-seabottom materials in the southern Beaufort Sea. Environment Canada, Beaufort Sea Project, Technical Report 22, 174 pp.

279

Hunter, J.A., Neave, K.G., MacAulay, H.A., Hobson, G.D., 1978. Interpretation of sub-seabottom permafrost in the Beaufort Sea by seismic methods. Part I: Seismic refraction methods. Proceedings, 3rd International Conference on Permafrost, Edmonton, Alberta. National Research Council of Canada, Ottawa, pp. 515–521. IPCC, Intergovernmental Panel on Climate Change, 2007. Climate Change 2007: The Physical Science Basis. In: Solomon, S., Qin, D., Manning, M., Chen, Z., Marquis, M., Averyt, K.B., Tignor, M., Miller,H.L. (Eds.), Contribution of Working Group I to the Fourth Assessment Report of the Intergovernmental Panel on Climate Change. Cambridge University Press, Cambridge, UK, 996 pp. James, T.S., Ivins, E.R., 1998. Predictions of Antarctic crustal motions driven by present-day ice sheet evolution and by isostatic memory of the Last Glacial Maximum. Journal of Geophysical Research 103 (B3), 4993–5017. James, T.S., Simon, K.M., Forbes, D.L., Dyke, A.S., Mate, D.J., 2010. Sea-level Projections for Five Pilot Communities of the Nunavut Climate Change Partnership. Geological Survey of Canada, Ottawa, Open File 6715, 23 pp. Jefferies, R.L., 1977. The vegetation of salt marshes at some coastal sites in Arctic North America. Journal of Ecology 65, 661–672. Jenner, K.A., Hill, P.R., 1998. Recent Arctic deltaic sedimentation, Olivier Islands, Mackenzie Delta, Northwest Territories, Canada. Sedimentology 45, 987–1004. Jezek, K.C., Liu, H., Zhao, Z., Li, B., 1999. Improving a digital elevation model of Antarctica using radar remote sensing and GIS techniques. Polar Geography 23 (3), 185–200. John, B.S., 1972. Evidence from the South Shetland Islands towards a glacial history of West Antarctica. In: Price, R.J., Sugden, D.E. (Eds.), Polar Geomorphology. Institute of British Geographers Special Publication, London, 4, 75–92. John, B.S., Sugden, D.E., 1971. Raised marine features and phases of glaciation in the South Shetland Islands. British Antarctic Survey Bulletin 24, 45–111. Jones, B.M., Hinkel, K.M., Arp, C.D., Eisner, W.R., 2008. Modern erosion rates and loss of coastal features and sites, Beaufort Sea coast, Alaska. Arctic 61 (4), 361–372. Jones, B.M., Arp, C.D., Jorgenson, M.T., Hinkel, K.M., Schmutz, J.A., Flint, P.L., 2009. Increase in the rate and uniformity of coastline erosion in Arctic Alaska. Geophysical Research Letters 36, L03503. doi:10.1029/2008GL036205. Jordan, J.W., Mason, O.K., 1999. A 5000 year record of intertidal peat stratigraphy and sea level change from northwest Alaska. Quaternary International 60 (1), 37–47. Jorgenson, M.T., Brown, J., 2005. Classification of the Alaskan Beaufort Sea coast and estimation of carbon and sediment inputs from coastal erosion. Geo-Marine Letters 25 (2), 69–80. Jorgenson, M.T., Shur, Y., 2007. Evolution of lakes and basins in northwest Alaska and discussion of the thaw-lake cycle. Journal of Geophysical Research 112, F02S17. doi:10.1029/2006JF000531. Joyce, J.R.F., 1950. Notes on ice-foot development, Neny Fjord, Graham Land, Antarctica. Journal of Geology 58 (6), 646–649. Judge, A.S., Pelletier, B.R., Norquay, I., 1987. Permafrost base and distribution of gas hydrates. In: Pelletier, B.R. (Ed.), Marine Science Atlas of the Beaufort Sea: Geology and Geophysics. Geological Survey of Canada, Ottawa, pp. 6–7. Kaplin, P.A., Selivanov, A.O., 2005. Holocene sea-level changes in the Russian sector of the European Arctic. In: Bauch, H.A., Pavlidis, Yu.A., Polyakova, Ye.I., Masishov, G.G., Koç, N. (Eds.), Pechora Sea Environments: Past, Present, and Future. Berichte zur Polar- und Meeresforschung 501, 39–48. Kempema, E.W., Reimnitz, E., Barnes, P.W., 1989. Sea ice sediment entrainment and rafting in the Arctic. Journal of Sedimentary Petrology 59 (2), 308–317. Kempema, E.W., Reimnitz, E., Barnes, P.W., 1990. Salt-water anchor ice formation: observations from the Alaskan Beaufort Sea and flume experiments. In: Ackley, S.F., Weeks, W.F. (Eds.), Sea Ice Properties and Processes. US Army Cold Regions Research and Engineering Laboratory, Hanover, NH, USA, Monograph. 90-1, pp. 114–116. Kempema, E.W., Reimnitz, E., 1991. Nearshore sediment transport by slush/brash ice in southern Lake Michigan. Proceedings, Coastal Sediments 91. American Society of Civil Engineers, New York, pp. 212–213. Kempema, E.W., Reimnitz, E., Barnes, P.W., 2001. Anchor-ice formation and ice rafting in southwestern Lake Michigan, U.S.A. Journal of Sedimentary Research 71, 346– 354. Kiernan, K., Mcconnell, A., 1999. Geomorphology of the sub-Antarctic Australian terrority of Heard Island – McDonald Island. Australian Geographer 30 (2), 159–195. King, C.A.M., Buckley, J.T., 1968. The analysis of stone size and shape in Arctic environments. Journal of Sedimentary Petrology 38, 482–520. Kirk, R.M., 1972. Antarctic beaches as natural hydraulic models. Proceedings 7th New Zealand Geography Conference (Hamilton). pp. 227–234. New Zealand Geographical Society, Hamilton, NZ. Kirk, R.M., 1991. Raised beaches, late Quaternary sea levels and deglacial sequences on the Victoria Land coast, Antarctica. In: Gillieson, D.S., Fitzsimons, S. (Eds.), Quaternary Research in Australian Antarctica: Future Directiions. Australian Defence Force Academy, Canberra, Special Publication 3, pp. 85–105.

280

Polar Coasts

Kirk, R.M., 2010. Antarctic coast. In: Bird, E.C.F. (Ed.), Encyclopedia of the World’s Coastal Landforms. Springer, Dordrecht, pp. 1464–1469. Kizyakov, A.I., Zimin, M.T., Leibman, M.O., Cherkashov, G.A., 2004. Mapping of the coasts of Yugorsky Peninsula, Kara Sea. Berichte zur Polar- und Meeresforschung 482, 80–83. Kleiber, H.P., Niessen, F., 1999. Late Pleistocene paleoriver channels on the Laptev Sea shelf – implications from sub-bottom profiling. In: Kassens, H., Bauch, H.A., Dmitrenko, I., Eicken, H., Hubberten, H.-W., Melles, M., Thiede, J., Timokhov, L. (Eds.), Land–Ocean Systems in the Siberian Arctic: Dynamics and History. Springer, Berlin, pp. 657–665. Kobayashi, N., 1985. Formation of thermoerosional niches into frozen bluffs due to storm surges on the Beaufort Sea coast. Journal of Geophysical Research 90 (C6), 11983– 11988. Kobayashi, N., Vidrine, J.C., Nairn, R.B., Solomon, S.M., 1999. Erosion of frozen cliffs due to storm surge on the Beaufort Sea coast. Journal of Coastal Research 15 (2), 332–344. Koch, L., 1928. Contribution to the glaciology of North Greenland. Meddelelser om Grønland 65, 181–464. Koster, T.A., 1988. Ancient and modern cold-climate aeolian sand deposition: a review. Journal of Quaternary Science 3, 69–83. Kovacs, A., 1983. Shore Ice Ride-Up and Pile-Up Features. Part 1: Alaska’s Beaufort Sea Coast. US Army Cold Regions Research and Engineering Laboratory, Report 83-9, 60 pp. Kovacs, A., Sodhi, D.S., 1980. Shore ice pile-up and ride-up: field observations, models, theoretical analyses. Cold Regions Science and Technology 2, 209–288. Kovacs, A., Sodhi, D.S., 1981. Ice pile-up and ride-up on Arctic and subArctic beaches. Coastal Engineering 5, 247–273. Kovacs, A., Sodhi, D.S., 1988. Onshore ice pile-up and ride-up. In: Chen, A.T., Leidersdorf, C.P. (Eds.), Observations and Theoretical Assessment: Arctic Coastal Processes and Slope Protection Designs. American Society of Civil Engineers, New York, pp. 108–142. Kwok, R., Cunningham, G.F., Wensnahan, M., Rigor, I., Zwally, H.J., Yi, D., 2009. Thinning and volume loss of the Arctic Ocean sea ice cover: 2003–2008. Journal of Geophysical Research 114, C07005. doi:10.1029/2009JC005312. Lachenbruch, A.H., Sass, J.H., 1982. Permafrost, heat flow and the geothermal regimes of Prudhoe Bay, Alaska. Journal of Geophysical Research 87 (B11), 9301–9316. Lajeunesse, P., Hanson, M.A., 2008. Field observations of recent transgression on northern and eastern Melville Island, western Canadian Arctic Archipelago. Geomorphology 101 (4), 618–630. Lantuit, H., Atkinson, D., Grigoriev, M., Rachold, V., Grosse, G., Hubberten, H., Overduin, P., Couture, N., 2008a. Coastal erosion history retrieval using multi-sensor imagery on the permafrost coasts of the Bykovsky Peninsula. Eos, Transactions American Geophysical Union, 89 (53), Fall Meeting Supplement, Abstract C13B-07. Lantuit, H., Overduin, P., Couture, N., 2010. A pan-Arctic view of Arctic coasts: a new high resolution coastline database from the Arctic Coastal Dynamics project. IPY Oslo Science Conference, Oslo, June 2010, Abstract http://hdl.handle.net/10013/ epic.35395 (accessed February 2011). Lantuit, H., Overduin, P.P., 2010. Where, how fast, and why Arctic permafrost coasts undergo coastal erosion? Third European Conference on Permafrost, Longyearbyen, Svalbard, June 2010, Abstract. http://hdl.handle.net/10113/epic.35469. Lantuit, H., Overduin, P.P., Couture, N., Aré, F., Atkinson, D., Brown, J., Cherkashov, G., Drozdov, D., Forbes, D.L., Graves-Gaylord, A., Grigoriev, M., Hubberten, H.-W., Jordan, J., Jorgenson, T., Ødegård, R.S., Ogorodov, S., Pollard, W., Rachold, V., Sedenko, S., Solomon, S., Steenhuisen, F., Streletskaya, I., Vasiliev, A., Wetterich, S., 2011. The Arctic Coastal Dynamics coastal database: a new classification scheme and statistics on Arctic permafrost coastlines. Estuaries and Coasts, doi:10.1007/s12237­ 010-9362-6, pp.18. Lantuit, H., Overduin, P.P., Couture, N., Ødegård, R., 2008b. Sensitivity of coastal erosion to ground ice contents: an Arctic-wide study based on the ACD classification of Arctic coasts. Proceedings of the 9th International Conference on Permafrost, Fairbanks. University of Alaska, Institute of Northern Engineering, pp. 1025–1029. Lantuit, H., Pollard, W.H., 2008. Fifty years of coastal erosion and retrogressive thaw slump activity on Herschel Island, southern Beaufort Sea, Yukon Territory, Canada. Geomorphology 95, 84–102. Lantuit, H., Rachold, V., Pollard, W.H., Steenhuisen, F., Ødegård, R., Hubberten, H.-W., 2009. Towards a calculation of organic carbon release from erosion of Arctic coasts using non-fractal coastline datasets. Marine Geology 257, 1–10. Laudien, J., Herrmann, M., Arntz, W.E., 2007. Soft bottom species richness and diversity as a function of depth and iceberg scour in Arctic glacial Kongsfjorden (Svalbard). Polar Biology 30, 1035–1046.

Lauriol, B., Gray, J.T., 1980. Processes responsible for the concentration of boulders in the intertidal zone in Leaf Basin, Ungava. In: McCann, S.B. (Ed.), The Coastline of Canada. Geological Survey of Canada, Ottawa, Paper 80-10, pp. 281–292. Lavoie, C., Allard, M., Hill, P.R., 2002. Holocene deltaic sedimentation along an emerging coast: Nastapoka River delta, eastern Hudson Bay, Québec. Canadian Journal of Earth Sciences 39 (4), 505–518. Leidersdorf, C.B., Hearon, G.E., Vaudrey, K.D., Swank, G., 2006. Strudel scour formation off Arctic river delta. Proceedings of the International Conference on Coastal Engineering. American Society of Civil Engineers, Reston, pp. 5312–5324. Leont’yev, I.O., 2003. Modeling erosion of sedimentary coasts in the western Russian Arctic. Coastal Engineering 47, 413–429. Leont’yev, I.O., 2004a. Coastal profile modeling along the Russian Arctic coast. Coastal Engineering 51, 779–794. Leont’yev, I.O., 2004b. Modeling study of coastal evolution in the Arctic regions. Berichte zur Polar- und Meeresforschunng 482, 203–205. Lewis, C.F.M., 1977. Bottom scour by sea ice in the southern Beaufort Sea. Beaufort Sea Project, Technical Report 23. Environment Canada, Victoria BC. Lewis, C.F.M., 1978. The frequency and magnitude of drift ice groundings from ice scour tracks in the Canadian Beaufort Sea. Proceedings, 4th International Conference on Port and Ocean Engineering under Arctic Conditions. Memorial University of Newfoundland, St. Johns, NL, pp. 568–579. Lewis, C.P., 1988. Mackenzie Delta Sedimentary Environments and Processes. Unpublished contract report, Water Resources Branch, Environment Canada, Ottawa, 395 pp. Lewis, C.P., Forbes, D.L., 1976. Coastal Sedimentary Processes and Sediments, Southern Beaufort Sea. Environment Canada, Beaufort Sea Project, Technical Report no. 24, 68 pp. and appendix. Liu, H., Jezek, K.C., 2004. A complete high-resolution coastline of Antarctica extracted from orthorectified Radarsat SAR imagery. Photogrammetric Engineering and Remote Sensing 70 (5), 605–616. Lønne, I., Nemec, W., 2004. High-Arctic fan delta recording deglaciation and environment disequilibrium. Sedimentology 51, 553–589. Mabin, M.C.G., 1982. Geomorphological Investigations at Ridley Beach. Report to Ross Dependency Research Committee, Antarctica New Zealand Archives, Christchurch (cited by Harrowfield, 2006). Mackay, J.R., 1959. Glacier ice-thrust features of the Yukon coast. Geographical Bulletin no. 13, 5–21. Mackay, J.R., 1963. The Mackenzie Delta Area, NWT. Geographical Branch, Ottawa, Memoir 8, 202 pp. Mackay, J.R., 1966. Segregated epigenetic ice and slumps in permafrost, Mackenzie Delta area, Northwest Territories. Geographical Bulletin 8, 59–80. Mackay, J.R., 1971. The origin of massive icy beds in permafrost, western Arctic coast, Canada. Canadian Journal of Earth Sciences 8, 397–422. Mackay, J.R., 1972. The world of underground ice. Annals of the Association of American Geographers 62, 1–22. Mackay, J.R., 1975. Fifty years (1935–1985) of coastal retreat west of Tuktoyaktuk, District of Mackenzie. Geological Survey of Canada Paper, 86-1A, 727–735. Mackay, J.R., Rampton, V.N., Fyles, J.G., 1972. Relic Pleistocene permafrost, western Arctic, Canada. Science 176, 1321–1323. Mahoney, A., Eicken, H., Shapiro, L., Grenfell, T.C., 2004. Ice motion and driving forces during a spring ice shove on the Alaska Chukchi coast. Journal of Glaciology 50, 195–207. Manson, G.K., Forbes, D.L., 2008. Climate-change impacts on an emergent Arctic shoreline, Hall Beach, NU. Proceedings, Arctic Change 2008. ArcticNet, Québec, pp.118–119. http://www.arctic-change2008.com/pdf/ac-programme.pdf (accessed February 2011). Mars, J.C., Houseknecht, D.W., 2007. Quantitative remote sensing study indicates doubling of coastal erosion rate in the past 50 years along a segment of the Arctic coast of Alaska. Geology 35 (7), 583–586. Marsh, P., Hey, M., 1989. The flooding hydrology of Mackenzie Delta lakes near Inuvik, NWT, Canada. Arctic 42, 41–49. Marsh, P., Ommaney, C.S.L. (Eds.), 1991. Mackenzie Delta: Environmental Interactions and Implications of Development. Proceedings of Workshop on the Mackenzie Delta, Saskatoon, 17-18 October 1989. Environment Canada, National Hydrology Research Institute, Saskatoon, 195 pp. Marsh, P., Lesack, L.F.W., Roberts, A., 1999. Lake sedimentation in the Mackenzie Delta, NWT. Hydrological Processes 13, 2499–2518. Marsh, W.M., Marsh, B.D., Dozier, J., 1973. Formation, structure, and geomorphic influence of Lake Superior icefoots. American Journal of Science 273, 48–64. Martin, S., 1981. Frazil ice in rivers and oceans. Annual Review of Fluid Mechanics 13, 379–397. Martin, S., Kauffman, P., 1981. A field and laboratory study of wave damping by grease ice. Journal of Glaciology 27, 283–313.

Polar Coasts

Martini, I.P., Cowell, D.W., Wickware, G.M., 1980. Geomorphology of southwestern James Bay: a low energy, emergent coast. In: McCann, S.B. (Ed.), The Coastline of Canada. Geological Survey of Canada, Ottowa, Paper 80-10, pp. 293–301. Martini, I.P., Jefferies, R.L., Morrison, R.I.G., Abraham, K.F., 2009. Polar coastal wetlands: development, structure, and land use. Chapter 4. In: Perillo, G., Wolanski, E., Cahoon, D., Brinson, M. (Eds.), Coastal Wetlands: an Integrated Ecosystems Approach. Elsevier, Amsterdam, pp. 119–155. Maslanik, J.A., Fowler, C., Stroeve, J., Drobot, S., Zwally, H.J., Yi, D., Emery, W., 2007. A younger, thinner Arctic ice cover: increased potential for rapid, extensive sea-ice loss. Geophysical Research Letters 34, L24501. doi:10.1029/2007GL032043. Mason, O.K., Jordan, J.W., 1993. Heightened North Pacific storminess during synchronous late Holocene erosion of northwest Alaska beach ridges. Quaternary Research 40 (1), 55–69. Mason, O.K., Hopkins, D.M., Plug, L., 1997. Chronology and paleoclimate of storm-induced erosion and episodic dune growth across Cape Espenberg Spit, Alaska, USA. Journal of Coastal Research 13 (3), 770–797. Masson, D., LeBlond, P.H., 1989. Spectral evolution of wind-generated surface gravity waves in a dispersed ice field. Journal of Fluid Mechanics 202, 43–81. Matthews, J.B., Stringer, W.J., 1984. Spring breakup and flushing of an Arctic lagoon estuary. Journal of Geophysical Research 89 (C2), 2073–2079. Matsuoka, T., Uratsuka, H., Nishio, F., Fukamachi, Y., 2002. Deriving sea-ice thickness and ice types in the Sea of Okhotsk using dual-frequency airborne SAR (Pi-SAR) data. Annals of Glaciology 34, 429–434. McCann, S.B., Carlisle, R.J., 1972. The nature of the ice-foot on the beaches of Radstock Bay, south-west Devon Island, NWT, Canada in the spring and summer of 1970. Polar Geomorphology. Institute of British Geographers, London, Special Publication no. 4, pp. 175–186. McCann, S.B., Dale, J.E., Hale, P.B., 1981. Subarctic tidal flats in areas of large tidal range, southern Baffin Island, eastern Canada. Géographie physique et Quaternaire 35, 183–204. McCann, S.B., Owens, E.H., 1969. The size and shape of sediments in three Arctic beaches, SE Devon Island, NWT. Arctic and Alpine Research 1, 267–278. McMinn, A., 2005. Antarctica, coastal ecology and geomorphology. In: Schwartz, M.L. (Ed), Encyclopedia of Coastal Science. Springer, Berlin, pp. 29–33. McLaren, P., 1982. The Coastal Geomorphology, Sedimentology and Processes of Eastern Melville and Western Byam Martin Islands, Canadian Arctic Archipelago. Bulletin 333. Geological Survey of Canada, Ottawa, 39 pp. Miller, G.H., Andrews, J.T., Short, S.K., 1977. The last interglacial–glacial cycle, Clyde foreland, Baffin Island, NWT: stratigraphy, biostratigraphy, and chronology. Canadian Journal of Earth Sciences 14 (12), 2824–2857. Milne, G.A., Gehrels, W.R., Hughes, C.W., Tamisiea, M.E., 2009. Identifying the causes of sea-level change. Nature Geoscience 2, 471–478. Mitrovica, J.X., Tamisiea, M.E., Davis, J.L., Milne, G.A., 2001. Recent mass balance of polar ice sheets inferred from patterns of global sea-level change. Nature 409, 1026– 1029. Moign, A., 1976. L’action des glaces flottantes sur le littoral et les fonds marins du Spitsberg central et nord-occidental. Revue de Géographie de Montréal 30, 51–64. Moign, A., Guilcher, A., 1967. Une flèche littorale en milieu périglaciaire arctique: la flèche de Sars (Spitsberg). Norois 56, 549–568. Møller, J.J., Yevzerov, V.Y., Kolka, V.V., Corner, G.D., 2002. Holocene raised-beach ridges and sea-ice-pushed boulders on the Kola Peninsula, northwest Russia: indicators of climatic change. The Holocene 12 (2), 169–176. Mueller, D.R., Copland, L., Hamilton, A., Stern, D., 2008. Examining Arctic ice shelves prior to the 2008 breakup. Eos, Transactions American Geophysical Union 89 (49), 502. doi:10.1029/2008EO490002. Murton, J.B., 2009. Stratigraphy and palaeoenvironments of Richards Island and the eastern Beaufort continental shelf during the last glacial–interglacial cycle. Permafrost and Periglacial Processes 20, 107–125. Murton, J., French, H., Lamothe, M., 1997. Late Wisconsinan erosion and aeolian deposition, Summer Island area, Pleistocene Mackenzie Delta, NWT. Canadian Journal of Earth Sciences 34, 190–199. Muto, T., Steel, R.J., 1992. Retreat of the front in a prograding delta. Geology 20, 967– 970. Naidu, A.S., Mowatt, T.C., Rawlinson, S.E., Weiss, H.V., 1984. Sediment characteristics of the lagoons of the Alaskan Beaufort Sea coast and evolution of Simpson Lagoon. In: Barnes, P.W., Schell, D.M., Reimnitz, E. (Eds.), The Alaskan Beaufort Sea: Ecosystems and Environments. Academic Press, Orlando, pp. 275–292. Nairn, R.B., Solomon, S., Kobayashi, N., Virdrine, J., 1998. Development and testing of a thermal–mechanical numerical model for predicting Arctic shore erosion processes. Proceedings, 7th Intenational Conference on Permafrost, Yellowknife. Collection Nordicana, Quebec, no. 55, pp. 789–795. Nichols, R.L., 1953. Geomophic observations at Thule, Greenland and Resolute Bay, Cornwallis Island, NWT. American Journal of Science 251, 268–275.

281

Nichols, R.L., 1961. Characteristics of beaches formed in polar climates. American Journal of Science 259, 694–708. Nichols, R.L., 1968. Coastal geomorphology, McMurdo Sound, Antarctica. Journal of Glaciology 7 (51), 449–478. Nielsen, N., 1985. Greenland. In: Bird, C.F., Schwartz, M.L. (Eds.), The World’s Coastline. Van Nostrand Reinhold, New York, pp. 261–265. Nikiforov, C.L., Dunaev, N.N., Ogorodov, S.A., Artemyev, A.B., 2003. Physical-geographic characteristic. In: Romankevich, E.A., Lisitzin, A.P., Vinogradov, M.E. (Eds.), The Pechora Sea: Integrated Research. ‘More’ Publications, Moscow, pp. 27–92 (in Russian). Nixon, J.F., 1988. Pile load tests in saline permafrost at Clyde River, Northwest Territories [now Nunavut]. Canadian Geotechnical Journal 25 (1), 24–32. Ogata, N., Yasuda, M., Kataoka, T., 1983. Effects of salt concentration on strength and creep behavior of artificially frozen soils. Cold Regions Science and Technology 8 (2), 139–153. Ogorodov, S.A., 2003. The Arctic coast of Russia: Appendix A. The geomorphology of the Pechora Sea coast. In: Bird, E.C.F. (Ed.), The Worlds Coasts: Online. Springer, Berlin, Section 9.4, pp. 1015–1018. Ogorodov, S.A., 2005a. Coastal morphology and dynamics of the Pechora Sea. In: Bauch, H.A., Pavlidis, Yu.A., Polyakova, Ye.I., Masishov, G.G., Koç, N. (Eds.), Pechora Sea Environments: Past, Present, and Future. Berichte zur Polar- und Meeresforschung 501, 103–112. Ogorodov, S.A., 2005b. The role of sea ice in coastal and sea bottom dynamics of the Pechora Sea. In: Bauch, H.A., Pavlidis, Yu.A., Polyakova, Ye.I., Masishov, G.G., Koç, N. (Eds.), Pechora Sea Environments: Past, Present, and Future. Berichte zur Polar­ und Meeresforschung 501, 113–124. Ogorodov, S., Kamalov, A., Zubakin, G., Gudoshnikov, Y.P., 2005. The role of sea ice in coastal and bottom dynamics in the Pechora Sea. Geo-Marine Letters 25, 146–152. Osterkamp, T.E., 2001. Sub-sea permafrost. In: Steele, J.H., Thorpe, S.A., Turekian, K.K. (Eds.), Encyclopedia of Ocean Sciences. Academic Press, San Diego, pp. 2902–2912. Osterkamp, T.E., Baker, G.C., Harrison, W.D., Matava, T., 1989. Characteristics of the active layer and shallow subsea permafrost. Journal of Geophysical Research 94 (C11), 16227–16236. Otsuka, N., Takahashi, Y., Kondo, H., Takeuchi, T., Saeki, H., 2005. Experimental study of behavior of ice floe run-up caused by tsunami. International Journal of Offshore and Polar Engineering 15, 34–39. Overduin, P.P., Hubberten, H.-W., Rachold, V., Romanovskii, N.N., Grigoriev, M.N., Kasymskaya, M., 2007. The evolution and degradation of coastal and offshore permafrost in the Laptev and East Siberian Seas during the last climate cycle. Geological Society of America, Special Paper 426, 97–111. Overeem, I., Wobus, C.W., Anderson, R.S., Clow, G.D., Urban, F.E., Stanton, T.P., 2009. Quantifying sea-ice loss as a driver of Arctic coastal erosion. Eos, Transactions American Geophysical Union 90 (52), Fall Meeting Supplement, Abstract EP43B-0658. Overland, J.E., Wang, M., 2007. Future regional Arctic sea ice declines. Geophyiscal Research Letters 34, L17705. doi:10.1029/2007GL030808. Owens, E.H., 1976. The effects of ice on the littoral zone at Richibucto Head, eastern New Brunswick. Revue de Géographie de Montréal 30, 95–104. Owens, E.H., Taylor, R.B., Miles, M., Forbes, D.L., 1981. Coastal Geology Mapping: An Example from the Sverdrup Lowland, District of Franklin. Geological Survey of Canada, Ottawa, Paper 81-1B, 39–48. Payne, A.J., Vieli, A., Shepherd, A.P., Wingham, D.J., Rignot, E., 2004. Recent dramatic thinning of largest West Antarctic ice stream triggered by oceans. Geophysical Research Letters 31, L23401. doi:10.1029/2004GL021284. Peltier, W.R., 2004. Global glacial isostasy and the surface of the ice-age Earth: the ICE-5G (VM2) model and GRACE. Annual Review of Earth and Planetary Science 32,111–149. Peterson, J.A., Finlayson, B.L., Qingsong, Z., 2004. Changing distribution of late Quaternary terrestrial, lacustrine and littoral environments in the Vestfold Hills, Antarctica. Hydrobiologia 165 (1), 221–226. Pollard, W., 2010. Northern Canada. In: Bird, E.C.F. (Ed.), Encyclopedia of the World’s Coastal Landforms. Springer, Dordrecht, pp. 169–176. Pritchard, H.D., Arthern, R.J., Vaughan, D.G., Edwards, L.A., 2009. Extensive dynamic thinning on the margins of the Greenland and Antarctic ice sheets. Nature 461,971–975. Proshutinsky, A., Ashik, I., Häkkinen, S., Hunke, E., Krishfield, R., Maltrud, M., Maslowski, W., Zhang, J., 2007. Sea level variability in the Arctic Ocean from AOMIP models. Journal of Geophysical Research 112, C04S08. doi:10.1029/ 2006JC003916. Proshutinsky, A., Ashik, I.M., Dvorkin, E.N., Häkkinen, S., Krishfield, R.A., Peltier, W.R., 2004. Secular sea level change in the Russian sector of the Arctic Ocean. Journal of Geophysical Research 109, C03042. doi:10.1029/2003JC002007. Qingsong, Z., Peterson, J.A., 1984. A geomorphology and Late Quaternary geology of the Vestfold Hills, Antarctica. Australian National Antarctic Research Expeditions Report, No. 133. A.G.P.S., Canberra.

282

Polar Coasts

Rachold, V., Are, F.E., Atkinson, D.E., Cherkashov, G., Solomon, S.M., 2005. Arctic coastal dynamics (ACD): an introduction. Geo-Marine Letters 25 (2), 63–68. Rachold, V., Bolshiyanov, D.Yu., Grigoriev, M.N., Hubberten, H.-W., Junker, R., Kinitsky, V.V., Merker, F., Overduin, P.P., Schneider, W., 2007. Near-shore Arctic subsea permafrost in transition. Eos, Transactions Americal Geophysical Union 88, 149–156. Rachold, V., Eicken, H., Gordeev, V.V., Grigoriev, M.N., Hubberten, H.-W., Lisitzin, A.P., Shevchenko, V.P., Schirrmeister, L., 2003b. Modern terrigenous organic carbon input to the Arctic Ocean. In: Stein, R., Macdonald, R.W. (Eds.), Organic Carbon Cycle in the Arctic Ocean: Present and Past. Springer, Berlin, pp. 33–55. Rachold, V., Grigoriev, M.N., Are, F.E., Solomon, S., Reimnitz, E., Kassens, H., Antonow, M., 2000. Coastal erosion vs. riverine sediment discharge in the Arctic Shelf seas. International Journal of Earth Sciences 89, 450–460. Rachold, V., Lack, M., Grigoriev, M.N., 2003a. A geo information system (GIS) for circum-Arctic coastal dynamics. Proceedings, 8th International Conference on Permafrost, Zürich. Balkema, Zürich, pp. 923–927. Rampton, V.N., 1982. Quaternary Geology of the Yukon Coastal Plain. Geological Survey of Canada, Ottawa, Bulletin 317, 49 pp. Rampton, V.N., 1988. Quaternary Geology of the Tuktoyaktuk Coastlands, Northwest Territories. Geological Survey of Canada, Ottawa, Memoir 423, 98 pp. Rampton, V.N., Mackay, J.R., 1971. Massive Ice and Icy Sediments throughout the Tuktoyaktuk Peninsula, Richards Island, and Nearby Areas, District of Mackenzie. Geological Survey of Canada, Ottawa, Paper 71-21, 16 pp. Raymond, C., Ivins, E.R., Heflin, M.B., James, T.S., 2004. Quasi-continuous global postioning system measurements of glacial isostatic deformation in the Northern Transantarctic Mountains. Global and Planetary Change 42, 295–303. Rearic, D.M., Barnes, P.W., Reimnitz, E., 1990. Bulldozing and resuspension of shallow-shelf sediment by ice keels: implications for Arctic sediment transport trajectories. Marine Geology 91, 133–147. Reimnitz, E., 2000. Interactions of river discharge with sea ice in proximity of Arctic deltas: a review. Polarforschung 70, 123–134. Reimnitz, E., Aré, F.E., 1998. Coastal bluff and shoreface comparison over 34 years indicates large supply of erosion products to Arctic seas. Polarforschung 68, 231–235. Reimnitz, E., Barnes, P.W., 1988. Evidence for sea-ice impact on Icy Reef, Beaufort Sea coast. In: Galloway, J.P., Hamilton, T.D. (Eds.), Geologic Studies in Alaska by the US Geological Survey during 1987. United States Geological Survey, Washington, DC, Circular 1016, pp.190–192. Reimnitz, E., Barnes, P.W., Harper, J.R., 1990. A review of beach nourishment from ice transport of shoreface materials, Beaufort Sea, Alaska. Journal of Coastal Research 6,439–470. Reimnitz, E., Barnes, P.W., Toimil, L.J., Melchior, J., 1977. Ice gouge recurrence and rates of sediment reworking, Beaufort Sea, Alaska. Geology 5, 405–408. Reimnitz, E., Bruder, K.F., 1972. River discharge into an ice-covered ocean and related sediment dispersal, Beaufort Sea, coast of Alaska. Geological Society of America Bulletin 83, 861–866. Reimnitz, E., Graves, S.M., Barnes, P.W., 1985. Beaufort Sea coastal erosion, shoreline evolution, and sediment dynamics. US Geological Survey, Open-File Report 85-380, 67 pp. Reimnitz, E., Kempema, E.W., 1982. Dynamic ice-wallow relief of northern Alaska’s nearshore. Journal of Sedimentary Petrology 52, 451–461. Reimnitz, E., Kempema, E.W., 1983. High rates of bedload transport measured from infilling rate of large strudel-scour craters in the Beaufort Sea, Alaska. Continental Shelf Research 1 (3), 237–251. Reimnitz, E., Kempema, E.W., 1987a. Field observations of slush ice generated during freeze-up in Arctic coastal waters. Marine Geology 77, 219–231. Reimnitz, E., Kempema, E.W., 1987b. Thirty-four-year shoreface evolution at a rapidly retreating Arctic coastal site. In: Galloway, J.P., Hamilton, T.D. (Eds.), Geologic Studies in Alaskas by the US Geological Survey during 1986. United States Geological Survey, Washington, DC, Circular 998, pp. 161–164. Reimnitz, E., Kempema, E.W., Barnes, P.W., 1987. Anchor ice, seabed freezing, and sediment dynamics in shallow Arctic seas. Journal of Geophysical Research 92 (C13), 14671–14678. Reimnitz, E., Maurer, D.K., 1979a. Effects of storm surges on the Beaufort Sea coast, northern Alaska. Arctic 32, 329–344. Reimnitz, E., Maurer, D.K., 1979b. Eolian sand deflation – a cause for gravel barrier islands in Arctic Alaska? Geology 7 (10), 507–510. Reimnitz, E., Rodeick, C.A., Wolf, S.C., 1974. Strudel scour: a unique Arctic marine geologic phenomenon. Journal of Sedimentary Petrology 44 (2), 409–420. Reimnitz, E., Toimil, L.J., Barnes, P.W., 1978. Arctic continental shelf morphology related to sea-ice zonation, Beaufort Sea, Alaska. Marine Geology 28, 179–210. Reimnitz, E., Wolf, S.C., 1998. Are North Slope Surface Alluvial Fans Pre-Holocene Relicts? US Geological Survey, Professional Paper 1605, 9 pp. Reinson, G.E., Rosen, P.S., 1982. Preservation of ice-formed features in a sub-Arctic sandy beach sequence: geologic implications. Journal of Sedimentary Petrology 52,463–471.

Rekant, P., Cherkashev, G., Vanstein, B., Krinitsky, P., 2005. Submarine permafrost in the nearshore zone of the southwestern Kara Sea. Geo-Marine Letters 25, 183–189. Rex, R.W., 1964. Arctic beaches, Barrow, Alaska. In: Miller, R.L. (Ed.), Papers in Marine Geology: Shepard Commemorative Volume. Macmillan, New York, pp. 384–400. Romanovskii, N.N., Hubberten, H.-W., Gavrilov, A.V., Eliseeva, A.A., Tipenko, G.S., 2005. Offshore permafrost and gas hydrate stability zone on the shelf of East Siberian seas. Geo-Marine Letters 25, 167–182. Romanovskii, N.N., Hubberten, H.-W., Gavrilov, A.V., Tumskoy, V.E., 2003. Permafrost of the east Siberian Arctic shelf and coastal lowlands. Quaternary Science Reviews 23, 1359–1369. Rosen, P.S., 1979. Boulder barricades in central Labrador. Journal of Sedimentary Petrology 49, 113–124. Ruz, M.-H., 1993. Coastal dune development in a thermokarst environment: some implications for environmental reconstruction, Tuktoyaktuk Peninsula, NWT. Permafrost and Periglacial Processes 4 (3), 255–264. Ruz, M.-H., Allard, M., 1994. Foredune development along a subarctic emergingn coastline, eastern Hudson Bay, Canada. Marine Geology 117, 57–74. Ruz, M.-H., Allard, M., 1995. Sedimentary structures of cold-climate coastal dunes, eastern Hudson Bay, Canada. Sedimentology 42 (5), 725–734. Ruz, M.-H., Héquette, A., Hill, P.R., 1992. A model of coastal evolution in a transgressed thermokarst topography, Canadian Beaufort Sea. Marine Geology 106, 251–278. Sadler, H.E., Serson, H.V., 1981. Fresh water anchor ice along an Arctic beach. Arctic 34 (1), 62–63. Sánchez-Garcia, L., Vonk, J., Charkin, A., Kosmach, D., Dudarev, O., Semiletov, I., Gustafsson, Ö., 2009. Remobilization and degradation of Myostah Island (Laptev Sea), as part of the collapsingn Arctic coastal ice complex. Geophysical Research Abstracts 11, EGU2009-2983. http://meetingorganizer.copernicus.org/EGU2009/ EGU2009-2983.pdf (accessed February 2011). Schirrmeister, L., Siegert, C., Kuznetsova, T., Kuzmina, S., Andreev, A., Kienast, F., Meyer, H., Bobrov, A., 2002. Paleoenvironmental and paleoclimatic records from permafrost deposits in the Arctic region of northern Siberia. Quaternary International 89, 97–118. Schirrmeister, L., Kunitsky, V., Grosse, G., Wetterich, S., Meyer, H., Schwamborn, G., Babiy, O., Derevyagin, A., Siegert, C., 2010. Sedimentary characteristics and origin of the late Pleistocene Ice Complex on northeast Siberian Arctic coastal lowlands and islands – a review. Quaternary International, pp.23. doi:10.1016/j. quaint.2010.04.004. Selivanov, A.O., 2003. The Arctic coast of Russia. In: Bird, E.C.F. (Ed.), The Worlds Coasts: Online. Springer, Berlin, Section 9.4, pp. 1008–1015. Sellmann, P.V., Brown, J., Lewellen, R.I., McKim, H., Merry, C., 1975. The Classification and Geomorphic Implications of Thaw Lakes on the Arctic Coastal Plain, Alaska. US Army, Cold Regions Research and Engineering Laboratory, Hanover, NH. Research Report 344, 21 pp. Sellmann, P.V., Hopkins, D.M., 1983. Sub-sea permafrost distribution on the Alaskan Shelf. Final Proceedings, Fourth International Conference on Permafrost. National Academy Press, Washington DC, pp. 75–82. Sempels, J.-M., 1987. The coastal morphology and sedimentology of Cape Hatt Peninsula. Arctic 40, Supp. 1, 10–19. Shaw, J., Taylor, R.B., Forbes, D.L., Ruz, M.-H., Solomon, S., 1998. Sensitivity of the Coasts of Canada to Sea-Level Rise. Geological Survey of Canada, Ottawa, Bulletin 505, 79 pp. + map. Shepherd, A., Wingham, D., Rignot, E., 2004. Warm ocean is eroding West Antarctic Ice Sheet. Geophysical Research Letters 31, L23402. doi:10.1029/2004GL021106. Short, A.D., 1975. Offshore bars along the Alaskan Arctic coast. Journal of Geology 83 (2), 209–221. Short, A.D., 1976. Observations on ice deposited by waves on Alaskan Arctic beavhes. Revue de Géographie de Montréal 30, 115–122. Short, A.D., 1979a. Barrier island development along the Alaskan–Yukon coastal plains: summary. Geological Society of America Bulletin (Part I) 90, 3–5. Short, A.D., 1979b. Barrier island development along the Alaskan–Yukon coastal plains. Geological Society of America Bulletin (Part II) 90, 77–103. Short, A.D., Coleman, J.M., Wright, L.D., 1975. Beach dynamics and nearshore morphology of the Beaufort Sea coast, Alaska. Louisiana State University, Baton Rouge. Coastal Studies Institute, Technical Report 185, 15 pp. Short, A.D., Wiseman, W.J., 1974. Freezeup processes on Arctic beaches. Arctic 27 (3), 215–224. Smale, D.A., Barnes, D.K.A., Fraser, K.P.P., 2007. The influence of depth, site exposure and season on the intensity of iceberg scouring in nearshore Antarctic waters. Polar Biology 30, 769–779. Smale, D.A., Brown, K.M., Barnes, D.K.A., Fraser, K.P.P., Clarke, A., 2008. Ice scour disturbance in Antarctic waters. Science 321, 371. Smith, J.M.B., Bayliss-Smith, T.P., 1998. Kelp-plucking: coastal erosion facilitated by the bull-kelp Durvillaea antarctica at subantarctic Macquarie Island. Antarctic Science 10 (4), 431–438.

Polar Coasts

Solomon, S.M., 2005. Spatial and temporal variability of shoreline change in the Beaufort-Mackenzie region, Northwest Territories, Canada. Geo-Marine Letters 25,127–137. Solomon, S.M., Covill, R., 1995. Impacts of the September 1993 storm on the Beaufort Sea. Proceedings Canadian Coastal Conference 1995; Canadian Coastal Science and Engineering Association, Dartmouth, pp. 779–795. Solomon, S.M., Forbes, D.L., Fraser, P., Moorman, B., Stevens, C.W., Whalen, D., 2008. Nearshore geohazards in the southern Beaufort Sea, Canada. Proceedings, 7th International Pipeline Conference, Calgary. American Society of Mechanical Engineers, New York, pp. 281–289 (paper IPC2008-64349). Solomon, S.M., Forbes, D.L., Kierstead, B., 1994. Coastal Impacts of climate change: Beaufort Sea erosion study. Geological Survey of Canada, Ottawa, Open File 2890, 85 pp. Solomon, S., Mudie, P.J., Cranston, R., Hamilton, T., Thibaudeau, S.A., Collins, E.S., 2000. Characterisation of marine and lacustrine sediments in a drowned thermokarst embayment, Richards Island, Beaufort Sea, Canada. International Journal of Earth Sciences 89 (3), 503–521. Squire, V.A., 2007. Of ocean waves and sea-ice revisited. Cold Regions Science and Technology 49, 110–133. Squire, V.A., Dugan, J.P., Wadhams, P., Rottier, P.J., Liu, L.A.K., 1995. Of ocean waves and sea-ice. Annual Review of Fluid Mechanics 27, 115–168. Squire, V.A., Moore, S.C., 1980. Direct measurement of the attenuation of ocean waves by pack ice. Nature 283, 365–368. St-Hilaire-Gravel, D., Bell, T., Forbes, D.L., 2010. Raised gravel beaches as proxy indicators of past sea-ice and wave conditions, Lowther Island, Canadian Arctic Archipelago. Arctic 63 (2), 213–226. Stroeve, J., Holland, M.M., Meier, W., Scambos, T., Serreze, M., 2007. Arctic sea ice decline: faster than forecast. Geophysical Research Letters 34, L09501. doi:10.1029/ 2007GL029703. Sugden, D.E., 1992. Antarctic ice sheets at risk? Nature 359, 775–776. Sverdrup, O., 1904. The New Land – Four Years in Arctic Regions. Longmans, Green, London, 2 volumes. Swithinbank, C.W.M., 1988. Glaciers of the World: Antarctica. US Geological Survey Professional Paper, Washington DC, 1386-B. Tanner, V., 1939. Om de blockrika strandgördlarna (boulder barricades) vid subarktiska oceankustar, förekomstsätt og upkomst. Terra 51, 157–165. Taylor, A.E., Dallimore, S.R., Judge, A.S., 1996. Late Quaternary history of the Mackenzie-Beaufort region, Arctic Canada, from modeling of permafrost temperatures. 2. The Mackenzie Delta – Tuktoyaktuk coastlands. Canadian Journal of Earth Sciences 33, 62–71. Taylor, R.B., 1978. The occurrence of grounded ice ridges and shore ice piling along the northern coast of Somerset Island, NWT. Arctic 31 (2), 133–149. Taylor, R.B., 1981. Observations of storm conditions in the coastal zone, Bylot Island, NWT. Proceedings, Workshop on Ice Action on Shores, Rimouski. National Research Council Canada, Ottawa, pp. 133–149. Taylor, R.B., Forbes, D.L., 1987. Ice-dominated shores of Lougheed Island: type examples for the northwest Queen Elizabeth Islands, Arctic Canada. Proceedings, Canadian Coastal Conference 87. National Research Council Canada, Ottawa, pp.33–48. Taylor, R.B., Hodgson, D., 1991. Coastal Studies in the Canadian Arctic Archipelago: Brock, Devon, Prince Patrick and the Polynia Islands, NWT. Geological Survey of Canada, Ottawa, Open File 2380, 57 pp. Taylor, R.B., McCann, S.B., 1976. The effect of sea and nearshore ice on coastal processes in Canadian Arctic Archipelago. Revue de Géographie de Montréal 30, 123–132. Taylor, R.B., McCann, S.B., 1983. Coastal depositional landforms in northern Canada. In: Dawson, S. (Ed.), Shorelines and Isostasy. Institute of British Geographers, London. Special Publication 16, 53–77. Taylor, R.J., 1981. Shoreline vegetation of the Arctic Alaska coast. Arctic 34 (1), 37–42. Todd, B.J., Dallimore, S.R., 1998. Electromagnetic and geological transect across permafrost terrain, Mackenzie River delta, Canada. Geophysics 63 (6), 1914–1924. Tsang, G., 1982. Frazil and Anchor Ice: A Monograph. Subcommittee on Hydraulics of Ice-Covered Rivers, Associate Committee on Hydrology, National Research Council Canada, Ottawa, 90 pp. Tsytovich, N.A., Kronik, Y.A., Markin, K.F., Aksenov, V.I. et al., 1978. Physical and mechanical properties of saline soils. In: Sanger, F.J., Hyde, P.J. (Eds.), USSR Contribution Permafrost International Conference (2nd), July 13-28, 1973. National Academies of Science, Washington, DC, pp. 238–247. Vasiliev, A., Kanevskiy, M., Cherkashov, G., Vanshtein, B., 2005. Coastal dynamics at the Barents and Kara Sea key sites. Geo-Marine Letters 25, 110–120. Vaughan, D.G., 2005. How does the Antarctic Ice Sheet affect sea level rise? Science 308, 1877–1878. Velicogna, I., 2009. Increasing rates of ice mass loss from the Greenland and Antarctic ice sheets revealed by GRACE. Geophysical Research Letters 36, L19503. doi:10.1029/2009GL040222.

283

Wadhams, P., 1973. Attenuation of swell by sea ice. Journal of Geophysical Research 78 (18), 3552–3563. Walker, H.J., 1969. Some aspects of erosion and sedimentation in an Arctic delta during breakup. Proceedings, Symposium on the Hydrology of Deltas, Bucharest. International Association of Scientific Hydrology, Brussels, Publication 90, pp. 209–219. Walker, H.J., 1974. The Colville River and the Beaufort Sea: some interactions. In: Reed, J.C., Slater, J.E. (Eds.), The Coast and Shelf of the Beaufort Sea. Proceedings of a Symposium on Beaufort Sea Coast and Shelf Research, San Francisco. Arctic Institute of North America, Arlington, pp. 513–540. Walker, H.J., 1976. Depositional environments in the Colville River delta. In: Miller, T.P. (Ed.), Recent and Ancient Sedimentary Environments in Alaska. Alaska Geological Society, Anchorage, AK, pp. C1–C22. Walker, H.J., 1985. Alaska. In: Bird, C.F., Schwartz, M.L. (Eds.), The World’s Coastline. Van Nostrand Reinhold, New York, pp. 1–7. Walker, H.J., 1998. Arctic deltas. Journal of Coastal Research 14 (3), 718–738. Walker, H.J., 2005a. Arctic coastal geomorphology. In: Schwartz, M.L. (Ed.), Encyclopedia of Coastal Science. Springer, Dordrecht, pp. 49–55. Walker, H.J., 2005b. Ice-bordered coasts. In: Schwartz, M.L. (Ed.), Encyclopedia of Coastal Science. Springer, Dordrecht, pp. 542–545. Walker, H.J., Hudson, P.F., 2003. Hydrologic and geomorphic processes in the Colville River delta, Alaska. Geomorphology 56, 291–303. Walker, H.J., McGraw, M., 2010. Alaska. In: Bird, E.C.F. (Ed.), Encyclopedia of the World’s Coastal Landforms. Springer, Berlin, pp. 5–14. Whitehouse, P.L., Allen, M.B., Milne, G.A., 2007. Glacial isostatic adjustment as a control on coastal processes: an example from the Siberian Arctic. Geology 35, 747–750. Wiseman, W.J., Coleman, J.M., Gregory, A., Hsu, S.A., Short, A.D., Suhayda, J.N., Walters, C.D., Wright, L.D., 1973. Alaskan Arctic Coastal Processes and Morphology. Louisiana State University, Baton Rouge. Coastal Studies Institute, Technical Report 149, 171 pp. Wobus, C.W., Anderson, R.S., Overeem, I., Matell, N., Urban, F.E., Clow, G.D., Holmes, C.D., Jones, B.M., 2008. Monitoring coastal erosion on the Beaufort Sea coast: erosion process and the relative roles of thermal and wave energy. Eos, Transactions American Geophysical Union 89 (53), Fall Meeting Supplement, Abstract C53A-03. Wobus, C.W., Anderson, R.S., Overeem, I., Urban, F.E., Clow, G.D., Stanton, T.P., 2009. Calibrating thermal erosion models along an Arctic coastline. Eos, Transactions American Geophysical Union 90 (52), Fall Meeting Supplement, Abstract EP33C-08. Wolfe, S.A., Dallimore, S.R., Solomon, S.M., 1998. Coastal permafrost investigations along a rapidly eroding shoreline, Tuktoyaktuk, NWT. Proceedings, 7th International Conference on Permafrost, Yellowknife. Collection Nordicana, Québec, no. 55, pp.1125–1131. Woodworth-Lynas, C.M.T., Josenhans, H.W., Barrie, J.V., Lewis, C.F.M., Parrott, D.R., 1991. The physical processes of seabed disturbance during iceberg grounding and scouring. Continental Shelf Research 11, 939–961. Wright, C.S., Priestley, R.E., 1922. Glaciology: British (Terra Nova) Antarctic Expedition 1910-1913. Harrison, London, 487 pp. Zenkovich, V.P., 1985. Arctic USSR. In: Bird, C.F., Schwartz, M.L. (Eds.), The World’s Coastline. Van Nostrand Reinhold, New York, pp. 863–871. Ziaja, W., Maciejowski, W., Ostafin, K., 2007. Northeastern Sørkappland Landscape Dynamics (Spitsbergen, Svalbard). Wydawnichtwo Uniwersytetu Jagiellońskiego, Kraków, 64 pp., +22 plates (ISBN 978-83-233-2317-4). Ziaja, W., Maciejowski, W., Ostafin, K., 2009. Coastal landscape dynamics in NE Sørkapp Land (SE Spitsbergen), 1900-2005. Ambio 38, 201-208. Zöckler, C., Douglas, T., Collen, B., Barry, T., Forbes, D.L., Loh, J., Gill, M., McRae, L., Sergienko, L., 2011. Ecological state of the circum-Arctic coast. In: Forbes, D.L. (Ed.). State of the Arctic Coast 2010 – Scientific Review and Outlook. International Arctic Science Committee, Land Ocean Interactions in the Coastal Zone, Arctic Monitoring and Assessment Programme, International Permafrost Association. LOICZ International Project Office, Geesthacht, Germany, pp. 39–56. Zubov, N.N., 1943. Arctic Ice. Isdatel’stvo Glavesevmorputi, Moscow, 360 pp. (in Russian) (English translation, 1963, US Naval Electronics Laboratory, San Diego, CA, 491 pp. (AD0426972, National Technical Information Service, Springfield, VA. Zumberge, J.H., Wilson, J.T., 1953. Effect of ice on shore development. Proceedings, 4th Conference on Coastal Engineering, Chicago. University of California, Berkeley, pp.201–205. Zwally, H.J., Comiso, J.C., Parkinson, C.L., Campbell, J., Carsey, F.D., Gloerson, P., 1983. Antarctic sea ice 1973–1976: Satellite Passive Microwave Observations. (Report SP-459). NASA Pub. Washington, DC, NASA, Scientific and Technical Information Branch.