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Island abandonment and sea-level rise: An historical analog from the Chesapeake Bay, USA
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Global Environmental Change 16 (2006) 40–47 www.elsevier.com/locate/gloenvcha
Island abandonment and sea-level rise: An historical analog from the Chesapeake Bay, USA Sheila J. Arenstam Gibbonsa, Robert J. Nichollsb, a
Department of Geography and Environmental Studies, Wilfrid Laurier University, 75 University Ave. W., Waterloo, Canada ON N2L 3C5 School of Civil Engineering and the Environment and Tyndall Centre for Climate Change Research, University of Southampton, Highfield, Southampton SO17 1BJ, UK
b
Received 25 November 2004; received in revised form 22 July 2005; accepted 22 October 2005
Abstract Small islands are widely agreed to be vulnerable to human-induced sea-level rise during the 21st century and beyond, with forced abandonment of some low-lying oceanic islands being a real possibility. A regional abandonment of islands in the Chesapeake Bay, USA provides an historical analog of such vulnerability as this has been linked to a mid 19th Century acceleration in relative sea-level rise. Using a case study approach for Holland Island, Maryland, this hypothesis was tested using a range of physical and human historical data. While sea-level rise was the underlying driver, this analysis shows that the abandonment was more complex than a direct response to sea-level rise. Between 1850 and 1900, Holland Island was a booming community and population increased from 37 to 253, with immigration causing the majority of the increase. At the same time, the upland area where people made their homes was steadily diminishing, losing about 15 ha or 38% of the total. After 1900, the island experienced a decrease in population to 169 in 1916, with final abandonment in 1918, with the exception of one family who left by 1920. Final abandonment was triggered by this depopulation as the population fell below a level that could support critical community services, and the community lost faith in their future on Holland Island. It is likely that similar social processes determined the abandonment of the other Chesapeake Bay islands. Looking to the future, it shows that many small low-lying islands could be abandoned due to sea-level rise long before they become physically uninhabitable. r 2005 Elsevier Ltd. All rights reserved. Keywords: Islands; Sea-level rise; Abandonment; Atoll nations
1. Introduction The Chesapeake Bay, USA has experienced significant relative sea-level rise since the mid 19th Century at rates of 30–40 cm/century (e.g., Kearney and Stevenson, 1991; Nicholls and Leatherman, 1996). There have been important natural system responses to this driver, including wetland degradation, upland to wetland conversion and island reduction and loss (Downs et al., 1994; Wray et al., 1995; Leatherman et al., 1995). However, the impacts on human society are less clear. Both Kearney and Stevenson (1991) and Leatherman (1992) associated sea-level rise and land loss with abandonment of most of the Chesapeake Bay islands by their resident populations early in the 20th Corresponding author. Tel.: +44 23 8059 4139; fax: +44 23 8059 5719.
E-mail address: [email protected] (R.J. Nicholls). 0959-3780/$ - see front matter r 2005 Elsevier Ltd. All rights reserved. doi:10.1016/j.gloenvcha.2005.10.002
Century. However, understanding the cause and effect relationships between these changes is more complex, including the role of sea-level rise versus other factors that might drive island abandonment. This paper explores the relationship between sea-level rise and island abandonment for Holland Island. It combines a number of methods to understand naturaland human-system changes on and hence the possible direct and indirect impact of sea-level rise on an island community. 2. Holland island Holland Island is located in the Chesapeake Bay, in Dorchester County, Maryland, approximately 11 km from the mainland (Fig. 1). In 1849, Holland Island occupied about 105 ha comprised of three low-elevation upland
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aerial photography, documentary evidence (historical land grants), geological surveys, and historical storm data. Historical coastal changes were mapped using NOS Tsheets and aerial photographs for Holland Island and neighboring islands for the years 1849–1989, including distinguishing areas of wetland and upland. For the purpose of this study, upland is defined as dry land above normal tides upon which homes and roads were built, including arable land. The methods are similar to those used by Downs et al. (1994) and Wray et al. (1995) on other Chesapeake Bay islands. Land loss prior to 1849 was reconstructed using historical source data following Kearney and Stevenson (1991). Socioeconomic data such as population trends, occupations trends, and trends in fish production were investigated for an approximately 70-year period from 1850 to 1920. Historical data sources included written histories and newspaper articles, United States census data, United Methodist Church records, Dorchester County land records, NOS T-sheets, historical statistics of fish production in the Chesapeake Bay. In addition, after extensive enquiries two elderly former island residents from Holland Island were located and interviewed about the abandonment on 28 March 1993.
4. Physical changes: 17th–20th century Fig. 1. Holland Island, Maryland and its environs.
7400 New York City Baltimore 7200 Sea Level (mm)
ridges running roughly north to south along the eastern and western edges of the island, and through the center. Wetland areas separated each ridge. As with most Chesapeake Bay islands, Holland Island is dominantly composed of silts and clay resulting in a lack of welldeveloped protective beaches. The western side of the island is exposed to waves in the main Chesapeake Bay, with a fetch of up to 29 km, while the eastern side of the island is much more sheltered with a fetch of no more than 3 km. During the years of habitation by European settlers beginning with the 17th century, a thriving community lived on Holland Island (Parks, 1972). By 1900, the island had about 70 buildings and an economy based on fisheries. Its more than 200 residents had established many community institutions such as a church, school, stores, and a post office. Yet within 20 years, all its year-round residents had abandoned the island.
Fig. 2 shows mean sea-level data from New York City (the longest US east coast record dating back to 1856), Baltimore (the longest Chesapeake Bay record) and Solomon’s Island, which is 60 km from Holland Island (Fig. 1). While they cover different periods, the data shows similar trends and it is meaningful to extrapolate observed sea-level rise from New York City to the Chesapeake Bay (cf. Douglas, 1991). The analysis suggests that from 1850 to
Solomons Island
7000
6800
3. Methodology In order to understand the human response to sea-level rise, it is important to quantify both physical and human changes. In this sense, the physical data provide the backdrop against which the social response is analyzed. Physical source data included mean sea-level data, National Ocean Service Topographic Sheets (NOS T-sheets),
6600 1850
1900
1950
2000
Time (years)
Fig. 2. Relative sea-level measurements from 1856 to 2000 for New York, Baltimore and Solomons Island. The data has been offset to allow easy viewing. Downloaded from http://www.pol.ac.uk/psmsl/.
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Table 1 Land loss on Holland Island, 1668–1989 Year
Area (ha)
Hectares lost since previous year
Percent reduction since previous year
Rate ha/yr since previous year
1668 1795 1849 1901 1942 1989
121.4 111.7 104.8 80.4 65.8 43.1
— 9.7 6.9 24.4 14.6 22.7
— 8% 6% 23% 18% 35%
— 0.08 0.13 0.47 0.36 0.48
Year 1989
Area (ha) 43.1
Hectares lost since 1668 78.3
Percent reduction since 1668 65%
Rate ha/yr since 1668 0.25
1920, Holland Island experienced a net relative rise in sea level of about 20 cm (or a linear rate of about 3 mm/yr). Land loss from documentary evidence and the historic maps is shown in Table 1 and Fig. 3. The average rate of land loss of Holland Island between 1668 and 1849 was 0.09 ha/yr. From 1849 to 1989 losses were much higher averaging 0.44 ha/yr (Table 1). This roughly fivefold acceleration of the rate of land loss is consistent with the results of Kearney and Stevenson (1991) for other Chesapeake Bay islands. Between 1849 and 1989, an upland area of 35.6 ha was lost at an average rate of 0.25 ha/yr, comprising an 89% net loss (Table 2). The loss of upland occurred because of a combination of edge erosion due to waves around the island perimeter (21.6 ha) and upland conversion into wetland of low-lying upland areas within the island perimeter (14 ha). The majority of the upland loss occurred along the western edge of Holland Island where nearly half the population lived. Between 1849 and 1901, the western upland ridge lost 48% of its area and had totally disappeared by 1952. In comparison, the eastern ridge lost only 1% of its area by 1901, and 69% by 1989 (Table 3). 5. Historical reconstruction: 1850–1920 Population trends of Holland Island indicate a period of sustained settlement and growth over 50 years (1850–1900), followed by a significant decline in population and total abandonment by 1920 (Fig. 4). Between 1850 and 1880, the population of Holland Island increased at nearly 2 persons/ yr, and nearly 8 persons/yr from 1880 to 1900. Although much of the increase in population was because of births to long-standing residents, immigration to Holland Island contributed more of the population increase. Between 1850 and 1900, 191 people immigrated to Holland Island, while there were 153 births, including those to immigrants. Between 1850 and 1880, the ratio of adults to children was approximately 2:1, but by 1900, the number of children had dramatically increased to a ratio of nearly 1:1. During the same time period as this population growth, the total land area was decreasing on the island. More importantly, the upland area on which people built their homes was decreasing. Holland Island’s population peaked
Fig. 3. Historical shoreline change on Holland Island from 1849 to 1989.
in 1900 with 253 residents at a population density of 10 people per hectare (1000 people/km2) (Table 4). This is higher than all other towns in Dorchester County (Walker, 1934) and one of the highest population densities on the entire Eastern Shore of Maryland at this time. This stresses
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Table 2 Upland loss on Holland Island through erosion and conversion into wetland, 1849–1989 Year
Upland area Hectares (ha) lost
Rate of loss Percent lost Upland (ha/yr) eroded (ha)
Erosion rate Upland (ha/yr) converted (ha)
Conversion rate (ha/yr)
Percent eroded
Percent converted
1849 1901 1989
40.2 25.3 4.6
— 14.9 20.7
— 0.29 0.23
— 37% 52%
— 9.9 11.7
— 0.19 0.13
— 5 9
— 0.1 0.1
— 66% 57%
— 34% 43%
Total
n.a.
35.6
0.25
89%
21.6
0.15
14
0.1
61%
39%
Table 3 Upland land loss for each ridge, 1849–1989 Year
Area (ha)
Area lost (ha)
Percent lost since 1849
Rate (ha/yr)
Western ridge 1849 1901 1989 Total
18.4 9.6 0 —
— 8.8 9.6 18.4
— 48% 52% 100%
— 0.17 0.11 0.13
Eastern ridge 1849 1901 1989 Total
14.6 14.5 4.4 —
— 0.01 10.1 10.2
— 1% 69% 70%
— 0.002 0.12 0.007
Hammok (central ridge) 1849 1901 1989 Total
2 0.5 0.2 —
— 1.5 0.3 1.8
— 75% 15% 90
— 0.03 0.003 0.13
the dramatic development of Holland Island from 1850 to 1900. The occupations of island residents also changed between 1850 and 1910 (Table 5). Out of the 37 residents in the 1850 census, 15 people were listed with occupations: 10 (or nearly 67%) of the employed residents listed their primary occupation as sailors, 4 (or 27%) were farmers, and 1 person was a carpenter. By 1910, the occupations of 65 people were identified. Nearly 90% of the employed residents were either oystermen or watermen. There was one teacher, one postmistress, and one minister. Four people were listed as merchants or sales ladies. Not one person listed farming as their primary occupation. This suggests a shift from land-based to water-based occupations as land loss occurred and the remaining upland areas were developed. The populations for 1910, 1916 and 1917 were 196, 169 and 145, respectively (see Parks, 1972) showing a steady decrease after 1900 with final abandonment before 1920. Interestingly, despite the post-1900 decline in population, 23 immigrants moved to Holland Island between 1900 and 1910, and the gross outmigration was actually larger. It was not possible to document when the residents first became aware of upland loss as a problem, but documentary evidence of an attempt to protect the upland from
erosion is apparent–a groin field is shown on the southwestern tip of the island on the 1901 NOS T sheet. These groins failed to stop the erosion. Population trends after 1900 show that the population of Holland Island began to decline. Given the high population density, there were only limited opportunities to relocate within the island after this time and as upland continued to be lost, so individual families appear to have been forced to leave Holland Island. The net migration of people after 1900 seems to exceed direct displacement by land loss as the population density declined. (Before 1900, internal relocation was possible within Holland Island as upland areas were still available, but this is speculative). During the years of habitation, the majority of the residents of Holland Island lived on the western ridge along the Chesapeake Bay (Parks, 1972). According to the 1901 NOS T-sheet, there were 23 buildings on the western ridge, compared to only 12 and 10 on the eastern and central ridges, respectively. (These building numbers are smaller than those reported by Parks (1972).) The western ridge was the largest area of upland on the island and also experienced the most extensive upland loss, and here we infer that residents were forced to leave after 1900. Considering that half of the residents lived on the western ridge and two-thirds of the population of 1900 remained in
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1916, it is tentatively assumed that some residents remained on the western ridge until at least 1916. 6. The abandonment of Holland Island Between 1850 and 1920, Holland Island was declining in size and this ultimately triggered abandonment. Habitable land remained on Holland Island throughout the 20th Century and even today one building remains, so loss of land was not a direct cause of abandonment. The following passage suggests that the final trigger to abandon Holland
Population
300
Population
200 Adults 100 children 0 1850
Abandoned
1900
1950
Time (years)
(a) 15 Population density
People / ha
- -based on dryland
10
5
0 1850
1900
1950
Time (years)
(b)
Fig. 4. (a) Population and (b) population density trends for the upland areas on Holland Island.
Island in 1918 was social in nature. Mrs. William Parks writes: After the people on the bay side were forced to move, those of us on the Holland Strait side, which was not bothered by washing, had to go too. Most of the people lived on the bay side. Those remaining on the strait side were not enough to support the church, the school, or the stores. When we tore down our houses, the church and school were dismantled too. (The Baltimore Sun, 1953). The interviews also confirmed that the island was abandoned because it was ‘‘washing away’’, a resulting loss of services and a general loss of faith in a future on Holland Island (Pers. commun. 23 March 1993). A key threshold appears to have been the closure of the school and stores, with total abandonment following rapidly thereafter. Fig. 5 summarizes the process of abandonment for Holland Island as identified in this research. The hazard of relative sea-level rise leads to upland loss. There was at least one (failed) attempt to stop the erosion and the beginnings of external relocation (Parks, 1972). This led to the post-1900 decline in the island population. The reduction in population triggered community decline, including closure of the island school, church, and post office by 1917. The final trigger for abandonment may have been a storm event in August 1918, which damaged several buildings, including the remains of the church and school. Holland’s Islandy was visited in August last by a windstorm that carried destruction in its wake. Our sturdy little church was moved bodily seven inches on its foundation, which crushed under the severe pressure; and the land on which the parsonage stood was washed away. y Finding no response on the part of the Islanders themselves to help save their own property (two preachers and one mechanic) manned the jacks and went to work. y The church needs to be fitted with new underpinning, and this will be done as soon as I can get
Table 4 Holland Island population density, 1849–1920 Year population 1849/50 1860 1870 1880 1887 1900/01 1910 1916 1917 1920
37 47 85 95 150 253 195 169 145 0
Total land area (ha)
Density (pers./ha)
Upland area (ha)
Density (pers./ha)
Source
104.8 100.4 96.0 91.6 88.5 80.4 76.8 74.6 74.1 —
0.4 0.5 0.9 1.0 1.7 3.1 2.5 2.3 2.0 —
40.2 37.3 34.4 31.5 29.5 25.3 23.0 21.6 21.3 —
0.9 1.3 2.5 3.0 5.1 10.0 8.5 7.8 6.8 —
Census Census Census Census Church records Census Census Church records Parks, 1972 —
Population change 1850–1900: +4.22 persons per year. Population change 1900–1916: 12.6 persons per year. Population change 1916–1918: 85 persons per year.
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Table 5 Holland Island occupations, 1850–1910 Category
Occupation
1850
1860
1870
1880
1900
1910
Water based
Sailor Oysterman Waterman Fisherman Total
10 0 0 0 10
0 0 0 0 0
10 12 0 0 22
20 4 0 1 25
0 61 0 1 62
0 18 40 58
Land based
Farmer/farm laborer Carpenter Total
4 1 5
3 0 3
1 0 1
1 0 1
0 0 0
0 0 0
Domestic
Keeping house Servant Total
0 0 0
0 0 0
11 6 17
16 3 19
0 0 0
0 0 0
Public
Teacher Physican Minister Postmistress Total
0 0 0 0 0
0 0 0 0 0
1 0 0 0 1
1 0 0 0 1
1 1 1 1 4
1 0 1 1 3
Other
Farmer & oysterman Merchant/sales lady Day laborer Retired Total
0 0 0 0 0
0 0 11 0 11
0 0 0 0 0
1 0 3 3 7
0 2 0 0 2
0 4 0 0 4
15 41%
14 30%
41 48%
53 56%
68 30%
65 33%
Hazard
Total % of Total population employed
Relative Sea-level Rise
Adaptation
Awareness
Erosion
Upland Conversion to Wetland
Upland Loss
Increased Storm/flood Effects
Salinization
Increased Damage
Degraded Water Resources
Individual (Family) Response Internal Relocation
Prevention Attempts
Abandonment
External Relocation Community Collapse Storm event
External event? Island Abandonment
Fig. 5. The chain of events from relative sea-level rise to island abandonment as observed for Holland Island.
the Islanders to place the necessary sand at the church to make the mortar. Later I sold the parsonage for $125.00, as by that time the waters had washed the ground away as far as the dining room. The island is now deserted, all of the inhabitants having left for the winter except one
family. Doubtless many of them will return for the summer crabbing season; so we will retain the church, and attempt to hold services for about five months a year, while the crabbers are about. There has been no service held since last October (1918) (Wilmington Conference Journals, 1919). Other than this report, the precise impact of the storms on the Holland Island community is uncertain, but it is noteworthy that the interviews of the former residents did not raise storm impacts as a major or recurring issue leading to abandonment (Pers. commun. March 28, 1993). The decision to abandon Holland Island does not appear to have been collective. However, the loss of community services appears to have been an important collective driver, and rather than maintain a smaller community everybody decided to leave. When interviewed, the former residents (Pers. commun. March 28, 1993) stated that individual families chose when and where to relocate. This is supported by the wide range of destinations chosen by the island residents, comprising at least 15 different Eastern Shore towns, and Smith and Tangiers Islands (Parks, 1972), which are still inhabited today. Changes to land- and water-based natural resources do not appear to be significant to abandonment—in fact fisheries drove the population growth at Holland Island from 1850 to 1900, and after abandonment many of the former residents maintained a water-based livelihood,
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including the father of the interviewees (Pers. commun. March 23, 1993). Although no evidence was found in the historical records, external triggers may have been important, with the influence of World War I or the flu pandemic of 1918 as possible factors. Again, the interviews did not identify any external factors as significant (Pers. commun. March 28, 1993). After abandonment, the attachment to the island remained as watermen visited the island during summer crabbing seasons for several years after 1918. Holland’s Island, which has been nearly washed away, no winter population being left and only the summer crabbers and fishermen now inhabiting the Island. (Wilmington Conference Journal, 1920). The interviewees’ mother missed Holland Island greatly and wished that they had never left the island (Pers. commun. March 28, 1993). Even decades later, several former residents and their descendants maintain contact and have even gathered for island reunions (e.g., Parks, 1972; Pers. commun. March 28, 1993). 7. Discussion/conclusions Coastal populations being driven from the world’s coasts by rising sea levels is a popular conception of the impacts of human-induced climate change and sea-level rise. This study demonstrates the efficacy of sea-level rise as an environmental hazard: a relative rise in sea level of about 0.2 m over 70 years triggered the abandonment of Holland Island, and by implication, many other Chesapeake Bay islands. As such these island abandonments represent an example of historical impacts of climate change on human society (cf. Smith et al., 2001). While this study supports the hypothesis that the Chesapeake Bay islands were abandoned due to acceleration in relative sea-level rise in the mid 19th Century, it suggests that the causes of final abandonment were more complex than a simple response to sea-level rise alone. On Holland Island, abandonment happened well before the island became physically uninhabitable and the extent of land loss did not determine when the island was finally abandoned—it was the socio-economic repercussions of the outmigration starting in 1900 that ultimately challenged the viability of the island’s community. The details of abandonment likely differed from island-to-island depending on specific circumstances and patterns of land loss and change (e.g., Downs et al., 1994; Wray et al., 1995). For instance, some small Chesapeake Bay islands disappeared completely (see Kearney and Stevenson, 1991), so abandonment may have been more directly forced by land loss than on Holland Island. Island abandonment on Holland Island may also have been encouraged by other island abandonment in the Chesapeake Bay, although this is speculative. Following the conceptual model of Smit and Pilifosova (2001), land loss on Holland island was sensitive to an
acceleration in sea-level rise as shown by the increased rates of land loss, the exposure grew significantly due to immigration, and the adaptive capacity was insufficient to adapt to these changes, except via abandonment (i.e. a forced retreat response (Klein et al., 2001)). (Note that the changes in exposure and adaptive capacity interacted: the population growth removed the possibility of internal relocation and hence reduced the adaptive capacity.) Collectively, this made the population of Holland Island highly vulnerable to a modest rise in relative sea level. While the silt/clay-based islands in the Chesapeake Bay are geologically very different to coral atolls, they share many common characteristics, in terms of high sensitivity, high exposure (for the main inhabited islands) and a low adaptive capacity given sea-level rise and climate change. Hence the Holland Island study strongly supports the model of Barnett and Adger (2003) concerning atoll nations and sea-level rise: that social issues may shape the response to sea-level rise more profoundly than the direct impacts. Barnett and Adger talk in terms of socialecological thresholds—on Holland Island the abandonment seems linked to a threshold related to loss of community services. During the abandonment of Holland Island, the residents reacted to actual change. Now there is already a strong awareness of the risk of accelerated sealevel rise (e.g., Church and Gregory, 2001; Nurse and Sem, 2001), even before we have definitive measurements that it is occurring. This could accelerate the process of abandonment shown in Fig. 5 as people lose faith in the future of low-lying islands based on the thought of the impacts of sea-level rise. A proposal to abandon the nation of Tuvalu, which has been widely reported (http://www.guardian. co.uk/comment/story/0%2C3604%2C582445%2C00.html; http://news.bbc.co.uk/1/hi/world/asia-pacific/2219001.stm), may reflect this process. Equally, they potentially have a wider range of adaptation options than the Holland Island residents had available to them, especially if international help is available. Therefore, the outcome of sea-level rise for low-lying islands remains uncertain. However, it is clear that adaptation must address more than the direct impacts of sea-level rise and climate change—the social dimension and especially the confidence of island communities and those who might invest in them must also be explicitly sustained if they are to survive and prosper. Further research of the abandonment of Chesapeake Bay islands could help to better understand the full range of these responses. This should include consideration of the two islands, which remain inhabited in the Chesapeake Bay, which has relevance to managing future impacts of sea-level rise. Tangiers Island now has a large revetment, which stops erosion on the exposed western shore and seemingly a thriving community, while on Smith Island natural processes continue unhindered, there is population decline, and abandonment appears to be a real possibility. More generally, this research suggests that any response to the threats of climate change and sea-level rise for islands
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needs to multi-faceted and should not just address technical issues in isolation (cf. Barnett and Adger, 2003). Our understanding of this issue remains limited and ripe for further research. Acknowledgments Most of this research was conducted when the authors were members of the University of Maryland from 1992 to 1994. Permission to interview two former residents of Holland Island is greatly appreciated. Barbara Carmichael, Robert D. Mitchell, Stephen P. Leatherman, Lorri K. Krebs and Gary Yohe and two anonymous reviewers provided constructive comments. Robert Nicholls was supported by the European Union Project DINASCOAST during the writing of this paper. References Baltimore Sun, 1953. ‘‘I Remember WhenyThe Bay Forced a Village to Move’’. October 18. Barnett, J., Adger, N.W., 2003. Climate dangers and atoll nations. Climatic Change 61, 321–337. Church, J.A., Gregory, J.M., 2001. Changes in Sea level. In: Houghton, J.T., Ding, Y., Griggs, D.J., Noguer, M., van der Linden, P.J., Xiaosu, D. (Eds.), Climate Change 2001. The Scientific Basis. Cambridge University Press, Cambridge, pp. 639–693. Douglas, B.C., 1991. Global sea-level rise. Journal of Geophysical Research 96 (C4), 6981–6992. Downs, L.L., Nicholls, R.J., Leatherman, S.P., Hautzenroder, J., 1994. Historic evolution of a Marsh Island: Bloodsworth Island, MD. Journal of Coastal Research 10, 1031–1044. Kearney, M.S., Stevenson, J.C., 1991. Island land loss and marsh vertical accretion rate: evidence for historical sea-level changes in Chesapeake Bay. Journal of Coastal Research 7 (2), 403–415. Klein, R.J.T., Nicholls, R.J., Ragoonaden, S., Capobianco, M., Aston, J., Buckley, E.N., 2001. Technological options for adaptation to
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climate change in coastal zones. Journal of Coastal Research 17 (3), 531–543. Leatherman, S.P., 1992. Coastal land loss in the Chesapeake Bay region: an historical analogy approach to global climate analysis and response. In: Schmandt, J. (Ed.), The Regions and Global Warming: Impacts and Response Strategies. Oxford University Press, Oxford. Leatherman, S.P., Chalfont, R., Pendleton, E., Funderburk, S., McCandless, T., 1995. Vanishing Lands: Sea Level, Society, and the Chesapeake Bay. University of Maryland Laboratory for Coastal Research and the US Fish and Wildlife Service, Chesapeake Bay Field Office 47pp. Nicholls, R.J., Leatherman, S.P., 1996. Adapting to sea-level rise: relative sea level trends to 2100 for the USA. Coastal Management 24 (4), 301–324. Nurse, L., Sem, G., 2001. Small Island States. In: McCarthy, J.J., Canziani, O.F., Leary, N.A., Dokken, D.J., White, K.S. (Eds.), Climate Change 2001: Impacts, Adaptation and Vulnerability. Cambridge University Press, Cambridge, pp. 843–875. Parks Sr., I.M., 1972. Vanishing Island: A True Story of Hollands Island. Unpublished pamphlet. Available at the Dorchester County Historical Society. Smit, B., Pilifosova, O., 2001. Adaptation to climate change in the context of sustainable development and equity. In: McCarthy, J.J., Canziani, O.F., Leary, N.A., Dokken, D.J., White, K.S. (Eds.), Climate Change 2001: Impacts, Adaptation and Vulnerability. Cambridge University Press, Cambridge, pp. 877–912. Smith, J.B., Schellnhuber, H.-J., Mirza, M.Q.G., 2001. Vulnerability to climate change and reasons for concern: a synthesis. In: McCarthy, J.J., Canziani, O.F., Leary, N.A., Dokken, D.J., White, K.S. (Eds.), Climate Change 2001: Impacts, Adaptation and Vulnerability. Cambridge University Press, Cambridge, pp. 913–967. Walker, W.P., 1934. Certain Financial Aspects of Local Governments in Maryland. State of Maryland State Planning Commission Report no. 3. pp. 9. Wilmington Conference Journals, United Methodist Church, 1919. Privately Published. Barrat’s Chapel and Museum, Frederica, Delaware. Wilmington Conference Journal, United Methodist Church, 1920. Privately Published. Barrat’s Chapel and Museum, Frederica, Delaware. Wray, R.D., Leatherman, S.P., Nicholls, R.J., 1995. Historic and future land loss for upland and marsh islands in the Chesapeake Bay, Maryland, USA. Journal of Coastal Research 11 (4), 1195–1203.
Global Environmental Change 16 (2006) 40–47 www.elsevier.com/locate/gloenvcha
Island abandonment and sea-level rise: An historical analog from the Chesapeake Bay, USA Sheila J. Arenstam Gibbonsa, Robert J. Nichollsb, a
Department of Geography and Environmental Studies, Wilfrid Laurier University, 75 University Ave. W., Waterloo, Canada ON N2L 3C5 School of Civil Engineering and the Environment and Tyndall Centre for Climate Change Research, University of Southampton, Highfield, Southampton SO17 1BJ, UK
b
Received 25 November 2004; received in revised form 22 July 2005; accepted 22 October 2005
Abstract Small islands are widely agreed to be vulnerable to human-induced sea-level rise during the 21st century and beyond, with forced abandonment of some low-lying oceanic islands being a real possibility. A regional abandonment of islands in the Chesapeake Bay, USA provides an historical analog of such vulnerability as this has been linked to a mid 19th Century acceleration in relative sea-level rise. Using a case study approach for Holland Island, Maryland, this hypothesis was tested using a range of physical and human historical data. While sea-level rise was the underlying driver, this analysis shows that the abandonment was more complex than a direct response to sea-level rise. Between 1850 and 1900, Holland Island was a booming community and population increased from 37 to 253, with immigration causing the majority of the increase. At the same time, the upland area where people made their homes was steadily diminishing, losing about 15 ha or 38% of the total. After 1900, the island experienced a decrease in population to 169 in 1916, with final abandonment in 1918, with the exception of one family who left by 1920. Final abandonment was triggered by this depopulation as the population fell below a level that could support critical community services, and the community lost faith in their future on Holland Island. It is likely that similar social processes determined the abandonment of the other Chesapeake Bay islands. Looking to the future, it shows that many small low-lying islands could be abandoned due to sea-level rise long before they become physically uninhabitable. r 2005 Elsevier Ltd. All rights reserved. Keywords: Islands; Sea-level rise; Abandonment; Atoll nations
1. Introduction The Chesapeake Bay, USA has experienced significant relative sea-level rise since the mid 19th Century at rates of 30–40 cm/century (e.g., Kearney and Stevenson, 1991; Nicholls and Leatherman, 1996). There have been important natural system responses to this driver, including wetland degradation, upland to wetland conversion and island reduction and loss (Downs et al., 1994; Wray et al., 1995; Leatherman et al., 1995). However, the impacts on human society are less clear. Both Kearney and Stevenson (1991) and Leatherman (1992) associated sea-level rise and land loss with abandonment of most of the Chesapeake Bay islands by their resident populations early in the 20th Corresponding author. Tel.: +44 23 8059 4139; fax: +44 23 8059 5719.
E-mail address: [email protected] (R.J. Nicholls). 0959-3780/$ - see front matter r 2005 Elsevier Ltd. All rights reserved. doi:10.1016/j.gloenvcha.2005.10.002
Century. However, understanding the cause and effect relationships between these changes is more complex, including the role of sea-level rise versus other factors that might drive island abandonment. This paper explores the relationship between sea-level rise and island abandonment for Holland Island. It combines a number of methods to understand naturaland human-system changes on and hence the possible direct and indirect impact of sea-level rise on an island community. 2. Holland island Holland Island is located in the Chesapeake Bay, in Dorchester County, Maryland, approximately 11 km from the mainland (Fig. 1). In 1849, Holland Island occupied about 105 ha comprised of three low-elevation upland
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aerial photography, documentary evidence (historical land grants), geological surveys, and historical storm data. Historical coastal changes were mapped using NOS Tsheets and aerial photographs for Holland Island and neighboring islands for the years 1849–1989, including distinguishing areas of wetland and upland. For the purpose of this study, upland is defined as dry land above normal tides upon which homes and roads were built, including arable land. The methods are similar to those used by Downs et al. (1994) and Wray et al. (1995) on other Chesapeake Bay islands. Land loss prior to 1849 was reconstructed using historical source data following Kearney and Stevenson (1991). Socioeconomic data such as population trends, occupations trends, and trends in fish production were investigated for an approximately 70-year period from 1850 to 1920. Historical data sources included written histories and newspaper articles, United States census data, United Methodist Church records, Dorchester County land records, NOS T-sheets, historical statistics of fish production in the Chesapeake Bay. In addition, after extensive enquiries two elderly former island residents from Holland Island were located and interviewed about the abandonment on 28 March 1993.
4. Physical changes: 17th–20th century Fig. 1. Holland Island, Maryland and its environs.
7400 New York City Baltimore 7200 Sea Level (mm)
ridges running roughly north to south along the eastern and western edges of the island, and through the center. Wetland areas separated each ridge. As with most Chesapeake Bay islands, Holland Island is dominantly composed of silts and clay resulting in a lack of welldeveloped protective beaches. The western side of the island is exposed to waves in the main Chesapeake Bay, with a fetch of up to 29 km, while the eastern side of the island is much more sheltered with a fetch of no more than 3 km. During the years of habitation by European settlers beginning with the 17th century, a thriving community lived on Holland Island (Parks, 1972). By 1900, the island had about 70 buildings and an economy based on fisheries. Its more than 200 residents had established many community institutions such as a church, school, stores, and a post office. Yet within 20 years, all its year-round residents had abandoned the island.
Fig. 2 shows mean sea-level data from New York City (the longest US east coast record dating back to 1856), Baltimore (the longest Chesapeake Bay record) and Solomon’s Island, which is 60 km from Holland Island (Fig. 1). While they cover different periods, the data shows similar trends and it is meaningful to extrapolate observed sea-level rise from New York City to the Chesapeake Bay (cf. Douglas, 1991). The analysis suggests that from 1850 to
Solomons Island
7000
6800
3. Methodology In order to understand the human response to sea-level rise, it is important to quantify both physical and human changes. In this sense, the physical data provide the backdrop against which the social response is analyzed. Physical source data included mean sea-level data, National Ocean Service Topographic Sheets (NOS T-sheets),
6600 1850
1900
1950
2000
Time (years)
Fig. 2. Relative sea-level measurements from 1856 to 2000 for New York, Baltimore and Solomons Island. The data has been offset to allow easy viewing. Downloaded from http://www.pol.ac.uk/psmsl/.
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Table 1 Land loss on Holland Island, 1668–1989 Year
Area (ha)
Hectares lost since previous year
Percent reduction since previous year
Rate ha/yr since previous year
1668 1795 1849 1901 1942 1989
121.4 111.7 104.8 80.4 65.8 43.1
— 9.7 6.9 24.4 14.6 22.7
— 8% 6% 23% 18% 35%
— 0.08 0.13 0.47 0.36 0.48
Year 1989
Area (ha) 43.1
Hectares lost since 1668 78.3
Percent reduction since 1668 65%
Rate ha/yr since 1668 0.25
1920, Holland Island experienced a net relative rise in sea level of about 20 cm (or a linear rate of about 3 mm/yr). Land loss from documentary evidence and the historic maps is shown in Table 1 and Fig. 3. The average rate of land loss of Holland Island between 1668 and 1849 was 0.09 ha/yr. From 1849 to 1989 losses were much higher averaging 0.44 ha/yr (Table 1). This roughly fivefold acceleration of the rate of land loss is consistent with the results of Kearney and Stevenson (1991) for other Chesapeake Bay islands. Between 1849 and 1989, an upland area of 35.6 ha was lost at an average rate of 0.25 ha/yr, comprising an 89% net loss (Table 2). The loss of upland occurred because of a combination of edge erosion due to waves around the island perimeter (21.6 ha) and upland conversion into wetland of low-lying upland areas within the island perimeter (14 ha). The majority of the upland loss occurred along the western edge of Holland Island where nearly half the population lived. Between 1849 and 1901, the western upland ridge lost 48% of its area and had totally disappeared by 1952. In comparison, the eastern ridge lost only 1% of its area by 1901, and 69% by 1989 (Table 3). 5. Historical reconstruction: 1850–1920 Population trends of Holland Island indicate a period of sustained settlement and growth over 50 years (1850–1900), followed by a significant decline in population and total abandonment by 1920 (Fig. 4). Between 1850 and 1880, the population of Holland Island increased at nearly 2 persons/ yr, and nearly 8 persons/yr from 1880 to 1900. Although much of the increase in population was because of births to long-standing residents, immigration to Holland Island contributed more of the population increase. Between 1850 and 1900, 191 people immigrated to Holland Island, while there were 153 births, including those to immigrants. Between 1850 and 1880, the ratio of adults to children was approximately 2:1, but by 1900, the number of children had dramatically increased to a ratio of nearly 1:1. During the same time period as this population growth, the total land area was decreasing on the island. More importantly, the upland area on which people built their homes was decreasing. Holland Island’s population peaked
Fig. 3. Historical shoreline change on Holland Island from 1849 to 1989.
in 1900 with 253 residents at a population density of 10 people per hectare (1000 people/km2) (Table 4). This is higher than all other towns in Dorchester County (Walker, 1934) and one of the highest population densities on the entire Eastern Shore of Maryland at this time. This stresses
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Table 2 Upland loss on Holland Island through erosion and conversion into wetland, 1849–1989 Year
Upland area Hectares (ha) lost
Rate of loss Percent lost Upland (ha/yr) eroded (ha)
Erosion rate Upland (ha/yr) converted (ha)
Conversion rate (ha/yr)
Percent eroded
Percent converted
1849 1901 1989
40.2 25.3 4.6
— 14.9 20.7
— 0.29 0.23
— 37% 52%
— 9.9 11.7
— 0.19 0.13
— 5 9
— 0.1 0.1
— 66% 57%
— 34% 43%
Total
n.a.
35.6
0.25
89%
21.6
0.15
14
0.1
61%
39%
Table 3 Upland land loss for each ridge, 1849–1989 Year
Area (ha)
Area lost (ha)
Percent lost since 1849
Rate (ha/yr)
Western ridge 1849 1901 1989 Total
18.4 9.6 0 —
— 8.8 9.6 18.4
— 48% 52% 100%
— 0.17 0.11 0.13
Eastern ridge 1849 1901 1989 Total
14.6 14.5 4.4 —
— 0.01 10.1 10.2
— 1% 69% 70%
— 0.002 0.12 0.007
Hammok (central ridge) 1849 1901 1989 Total
2 0.5 0.2 —
— 1.5 0.3 1.8
— 75% 15% 90
— 0.03 0.003 0.13
the dramatic development of Holland Island from 1850 to 1900. The occupations of island residents also changed between 1850 and 1910 (Table 5). Out of the 37 residents in the 1850 census, 15 people were listed with occupations: 10 (or nearly 67%) of the employed residents listed their primary occupation as sailors, 4 (or 27%) were farmers, and 1 person was a carpenter. By 1910, the occupations of 65 people were identified. Nearly 90% of the employed residents were either oystermen or watermen. There was one teacher, one postmistress, and one minister. Four people were listed as merchants or sales ladies. Not one person listed farming as their primary occupation. This suggests a shift from land-based to water-based occupations as land loss occurred and the remaining upland areas were developed. The populations for 1910, 1916 and 1917 were 196, 169 and 145, respectively (see Parks, 1972) showing a steady decrease after 1900 with final abandonment before 1920. Interestingly, despite the post-1900 decline in population, 23 immigrants moved to Holland Island between 1900 and 1910, and the gross outmigration was actually larger. It was not possible to document when the residents first became aware of upland loss as a problem, but documentary evidence of an attempt to protect the upland from
erosion is apparent–a groin field is shown on the southwestern tip of the island on the 1901 NOS T sheet. These groins failed to stop the erosion. Population trends after 1900 show that the population of Holland Island began to decline. Given the high population density, there were only limited opportunities to relocate within the island after this time and as upland continued to be lost, so individual families appear to have been forced to leave Holland Island. The net migration of people after 1900 seems to exceed direct displacement by land loss as the population density declined. (Before 1900, internal relocation was possible within Holland Island as upland areas were still available, but this is speculative). During the years of habitation, the majority of the residents of Holland Island lived on the western ridge along the Chesapeake Bay (Parks, 1972). According to the 1901 NOS T-sheet, there were 23 buildings on the western ridge, compared to only 12 and 10 on the eastern and central ridges, respectively. (These building numbers are smaller than those reported by Parks (1972).) The western ridge was the largest area of upland on the island and also experienced the most extensive upland loss, and here we infer that residents were forced to leave after 1900. Considering that half of the residents lived on the western ridge and two-thirds of the population of 1900 remained in
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1916, it is tentatively assumed that some residents remained on the western ridge until at least 1916. 6. The abandonment of Holland Island Between 1850 and 1920, Holland Island was declining in size and this ultimately triggered abandonment. Habitable land remained on Holland Island throughout the 20th Century and even today one building remains, so loss of land was not a direct cause of abandonment. The following passage suggests that the final trigger to abandon Holland
Population
300
Population
200 Adults 100 children 0 1850
Abandoned
1900
1950
Time (years)
(a) 15 Population density
People / ha
- -based on dryland
10
5
0 1850
1900
1950
Time (years)
(b)
Fig. 4. (a) Population and (b) population density trends for the upland areas on Holland Island.
Island in 1918 was social in nature. Mrs. William Parks writes: After the people on the bay side were forced to move, those of us on the Holland Strait side, which was not bothered by washing, had to go too. Most of the people lived on the bay side. Those remaining on the strait side were not enough to support the church, the school, or the stores. When we tore down our houses, the church and school were dismantled too. (The Baltimore Sun, 1953). The interviews also confirmed that the island was abandoned because it was ‘‘washing away’’, a resulting loss of services and a general loss of faith in a future on Holland Island (Pers. commun. 23 March 1993). A key threshold appears to have been the closure of the school and stores, with total abandonment following rapidly thereafter. Fig. 5 summarizes the process of abandonment for Holland Island as identified in this research. The hazard of relative sea-level rise leads to upland loss. There was at least one (failed) attempt to stop the erosion and the beginnings of external relocation (Parks, 1972). This led to the post-1900 decline in the island population. The reduction in population triggered community decline, including closure of the island school, church, and post office by 1917. The final trigger for abandonment may have been a storm event in August 1918, which damaged several buildings, including the remains of the church and school. Holland’s Islandy was visited in August last by a windstorm that carried destruction in its wake. Our sturdy little church was moved bodily seven inches on its foundation, which crushed under the severe pressure; and the land on which the parsonage stood was washed away. y Finding no response on the part of the Islanders themselves to help save their own property (two preachers and one mechanic) manned the jacks and went to work. y The church needs to be fitted with new underpinning, and this will be done as soon as I can get
Table 4 Holland Island population density, 1849–1920 Year population 1849/50 1860 1870 1880 1887 1900/01 1910 1916 1917 1920
37 47 85 95 150 253 195 169 145 0
Total land area (ha)
Density (pers./ha)
Upland area (ha)
Density (pers./ha)
Source
104.8 100.4 96.0 91.6 88.5 80.4 76.8 74.6 74.1 —
0.4 0.5 0.9 1.0 1.7 3.1 2.5 2.3 2.0 —
40.2 37.3 34.4 31.5 29.5 25.3 23.0 21.6 21.3 —
0.9 1.3 2.5 3.0 5.1 10.0 8.5 7.8 6.8 —
Census Census Census Census Church records Census Census Church records Parks, 1972 —
Population change 1850–1900: +4.22 persons per year. Population change 1900–1916: 12.6 persons per year. Population change 1916–1918: 85 persons per year.
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Table 5 Holland Island occupations, 1850–1910 Category
Occupation
1850
1860
1870
1880
1900
1910
Water based
Sailor Oysterman Waterman Fisherman Total
10 0 0 0 10
0 0 0 0 0
10 12 0 0 22
20 4 0 1 25
0 61 0 1 62
0 18 40 58
Land based
Farmer/farm laborer Carpenter Total
4 1 5
3 0 3
1 0 1
1 0 1
0 0 0
0 0 0
Domestic
Keeping house Servant Total
0 0 0
0 0 0
11 6 17
16 3 19
0 0 0
0 0 0
Public
Teacher Physican Minister Postmistress Total
0 0 0 0 0
0 0 0 0 0
1 0 0 0 1
1 0 0 0 1
1 1 1 1 4
1 0 1 1 3
Other
Farmer & oysterman Merchant/sales lady Day laborer Retired Total
0 0 0 0 0
0 0 11 0 11
0 0 0 0 0
1 0 3 3 7
0 2 0 0 2
0 4 0 0 4
15 41%
14 30%
41 48%
53 56%
68 30%
65 33%
Hazard
Total % of Total population employed
Relative Sea-level Rise
Adaptation
Awareness
Erosion
Upland Conversion to Wetland
Upland Loss
Increased Storm/flood Effects
Salinization
Increased Damage
Degraded Water Resources
Individual (Family) Response Internal Relocation
Prevention Attempts
Abandonment
External Relocation Community Collapse Storm event
External event? Island Abandonment
Fig. 5. The chain of events from relative sea-level rise to island abandonment as observed for Holland Island.
the Islanders to place the necessary sand at the church to make the mortar. Later I sold the parsonage for $125.00, as by that time the waters had washed the ground away as far as the dining room. The island is now deserted, all of the inhabitants having left for the winter except one
family. Doubtless many of them will return for the summer crabbing season; so we will retain the church, and attempt to hold services for about five months a year, while the crabbers are about. There has been no service held since last October (1918) (Wilmington Conference Journals, 1919). Other than this report, the precise impact of the storms on the Holland Island community is uncertain, but it is noteworthy that the interviews of the former residents did not raise storm impacts as a major or recurring issue leading to abandonment (Pers. commun. March 28, 1993). The decision to abandon Holland Island does not appear to have been collective. However, the loss of community services appears to have been an important collective driver, and rather than maintain a smaller community everybody decided to leave. When interviewed, the former residents (Pers. commun. March 28, 1993) stated that individual families chose when and where to relocate. This is supported by the wide range of destinations chosen by the island residents, comprising at least 15 different Eastern Shore towns, and Smith and Tangiers Islands (Parks, 1972), which are still inhabited today. Changes to land- and water-based natural resources do not appear to be significant to abandonment—in fact fisheries drove the population growth at Holland Island from 1850 to 1900, and after abandonment many of the former residents maintained a water-based livelihood,
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including the father of the interviewees (Pers. commun. March 23, 1993). Although no evidence was found in the historical records, external triggers may have been important, with the influence of World War I or the flu pandemic of 1918 as possible factors. Again, the interviews did not identify any external factors as significant (Pers. commun. March 28, 1993). After abandonment, the attachment to the island remained as watermen visited the island during summer crabbing seasons for several years after 1918. Holland’s Island, which has been nearly washed away, no winter population being left and only the summer crabbers and fishermen now inhabiting the Island. (Wilmington Conference Journal, 1920). The interviewees’ mother missed Holland Island greatly and wished that they had never left the island (Pers. commun. March 28, 1993). Even decades later, several former residents and their descendants maintain contact and have even gathered for island reunions (e.g., Parks, 1972; Pers. commun. March 28, 1993). 7. Discussion/conclusions Coastal populations being driven from the world’s coasts by rising sea levels is a popular conception of the impacts of human-induced climate change and sea-level rise. This study demonstrates the efficacy of sea-level rise as an environmental hazard: a relative rise in sea level of about 0.2 m over 70 years triggered the abandonment of Holland Island, and by implication, many other Chesapeake Bay islands. As such these island abandonments represent an example of historical impacts of climate change on human society (cf. Smith et al., 2001). While this study supports the hypothesis that the Chesapeake Bay islands were abandoned due to acceleration in relative sea-level rise in the mid 19th Century, it suggests that the causes of final abandonment were more complex than a simple response to sea-level rise alone. On Holland Island, abandonment happened well before the island became physically uninhabitable and the extent of land loss did not determine when the island was finally abandoned—it was the socio-economic repercussions of the outmigration starting in 1900 that ultimately challenged the viability of the island’s community. The details of abandonment likely differed from island-to-island depending on specific circumstances and patterns of land loss and change (e.g., Downs et al., 1994; Wray et al., 1995). For instance, some small Chesapeake Bay islands disappeared completely (see Kearney and Stevenson, 1991), so abandonment may have been more directly forced by land loss than on Holland Island. Island abandonment on Holland Island may also have been encouraged by other island abandonment in the Chesapeake Bay, although this is speculative. Following the conceptual model of Smit and Pilifosova (2001), land loss on Holland island was sensitive to an
acceleration in sea-level rise as shown by the increased rates of land loss, the exposure grew significantly due to immigration, and the adaptive capacity was insufficient to adapt to these changes, except via abandonment (i.e. a forced retreat response (Klein et al., 2001)). (Note that the changes in exposure and adaptive capacity interacted: the population growth removed the possibility of internal relocation and hence reduced the adaptive capacity.) Collectively, this made the population of Holland Island highly vulnerable to a modest rise in relative sea level. While the silt/clay-based islands in the Chesapeake Bay are geologically very different to coral atolls, they share many common characteristics, in terms of high sensitivity, high exposure (for the main inhabited islands) and a low adaptive capacity given sea-level rise and climate change. Hence the Holland Island study strongly supports the model of Barnett and Adger (2003) concerning atoll nations and sea-level rise: that social issues may shape the response to sea-level rise more profoundly than the direct impacts. Barnett and Adger talk in terms of socialecological thresholds—on Holland Island the abandonment seems linked to a threshold related to loss of community services. During the abandonment of Holland Island, the residents reacted to actual change. Now there is already a strong awareness of the risk of accelerated sealevel rise (e.g., Church and Gregory, 2001; Nurse and Sem, 2001), even before we have definitive measurements that it is occurring. This could accelerate the process of abandonment shown in Fig. 5 as people lose faith in the future of low-lying islands based on the thought of the impacts of sea-level rise. A proposal to abandon the nation of Tuvalu, which has been widely reported (http://www.guardian. co.uk/comment/story/0%2C3604%2C582445%2C00.html; http://news.bbc.co.uk/1/hi/world/asia-pacific/2219001.stm), may reflect this process. Equally, they potentially have a wider range of adaptation options than the Holland Island residents had available to them, especially if international help is available. Therefore, the outcome of sea-level rise for low-lying islands remains uncertain. However, it is clear that adaptation must address more than the direct impacts of sea-level rise and climate change—the social dimension and especially the confidence of island communities and those who might invest in them must also be explicitly sustained if they are to survive and prosper. Further research of the abandonment of Chesapeake Bay islands could help to better understand the full range of these responses. This should include consideration of the two islands, which remain inhabited in the Chesapeake Bay, which has relevance to managing future impacts of sea-level rise. Tangiers Island now has a large revetment, which stops erosion on the exposed western shore and seemingly a thriving community, while on Smith Island natural processes continue unhindered, there is population decline, and abandonment appears to be a real possibility. More generally, this research suggests that any response to the threats of climate change and sea-level rise for islands
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needs to multi-faceted and should not just address technical issues in isolation (cf. Barnett and Adger, 2003). Our understanding of this issue remains limited and ripe for further research. Acknowledgments Most of this research was conducted when the authors were members of the University of Maryland from 1992 to 1994. Permission to interview two former residents of Holland Island is greatly appreciated. Barbara Carmichael, Robert D. Mitchell, Stephen P. Leatherman, Lorri K. Krebs and Gary Yohe and two anonymous reviewers provided constructive comments. Robert Nicholls was supported by the European Union Project DINASCOAST during the writing of this paper. References Baltimore Sun, 1953. ‘‘I Remember WhenyThe Bay Forced a Village to Move’’. October 18. Barnett, J., Adger, N.W., 2003. Climate dangers and atoll nations. Climatic Change 61, 321–337. Church, J.A., Gregory, J.M., 2001. Changes in Sea level. In: Houghton, J.T., Ding, Y., Griggs, D.J., Noguer, M., van der Linden, P.J., Xiaosu, D. (Eds.), Climate Change 2001. The Scientific Basis. Cambridge University Press, Cambridge, pp. 639–693. Douglas, B.C., 1991. Global sea-level rise. Journal of Geophysical Research 96 (C4), 6981–6992. Downs, L.L., Nicholls, R.J., Leatherman, S.P., Hautzenroder, J., 1994. Historic evolution of a Marsh Island: Bloodsworth Island, MD. Journal of Coastal Research 10, 1031–1044. Kearney, M.S., Stevenson, J.C., 1991. Island land loss and marsh vertical accretion rate: evidence for historical sea-level changes in Chesapeake Bay. Journal of Coastal Research 7 (2), 403–415. Klein, R.J.T., Nicholls, R.J., Ragoonaden, S., Capobianco, M., Aston, J., Buckley, E.N., 2001. Technological options for adaptation to
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