- Email: [email protected]
The Canada-Japan SARES project on the first-year ice of Saroma-ko Lagoon (northern Hokkaido, Japan) and Resolute Passage (Canadian High Arctic)
%ournalof Marine Systems 11 ( 19971 1-8
a a
Department of Polar Biology, National Institute of Polar Research. 9-10, Saga I-Chome, ltabmhi-ku, Tokyo 173. Japan b Df!partement de biologie. Universite’Lural. Quibec. Qut!. GIK 7P4. Canada Received 14 October 1994; accepted 7 July 1995
Abstract A joint Canada-Japan project was conducted on the first-year ice of Saroma-ko Lagoon (northern do, Japan) and Resolute Passage (Northwest Territories, Canada) during the winter and spring of 1992. Objectives of the SARES project were to (1) measure the activity of the biological CO, pump under the first-year sea ice and (2) characterize its main physical controls. The two study sites exhibit contrasting characteristics. Among others, Saroma-ko southernmost area in the Northern Hemisphere with seasonal sea ice whereas Resolute Passage is one of t areas with recurrent first-year sea ice. It was hypothesized that such different characteristics would influence variables that determine the downward flux of biogenic carbon, e.g., hydrodynamics, nutrient replenishment, growth of ice algae and phytoplankton, transfer of primary production to the herbivorous and microbial webs, and sedimentation of biogenic particles. Mea!.ured variables included meteorology, hydrodynamics, prim&at-yproduction and nutrient effects, microbial web dynamics, production and grazing of zooplankton and ichthyoplankton, and sedimentation of algae and faecal pellets. The project involved 30 Canadian and 25 Japanese scientists, graduate students and technicians from seven institutions in Canada and twelve in Japan. Keywords: Arctic, first year sea Ice, biological CO, pump
1. Historical A joint Canada-Japan project was conducted on the first-year ice of Saroma-ko Lagoon (Northern Hokkaido, Japan) and Resolute Passage (Northwest
* Corresponding author. Phone: 81 3 3962 603 1. Fax: 81 3 3962 5743. E-mail: [email protected]. ’M. Fukuchi and L. Legendre are the coordinators of the SARES project.
Territories, Canada) during the winter and spring of 1992 (Fig. I). Overall, 30 Canadian and 25 Japanese scientists, graduate students and technicians from seven institutions in Canada and twelve in Japan participated in the planning of the SARES (Saroma-Resolute) project and field expeditions as well as the subsequent data analyses (Table 1). This major oceanographic venture was within the framework of the Canada-Japan Agreement on Cooperation in Science and Technology.
0924-7963/97/$17.00 Copyright 0 1997 Elsevier Science B.V. All rights reserved. PII SO924-7963(96)00022-X
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M. F~k~cki et al. / Jownal of Marine System I I (1997) l-8
Table 1 Principal investigators and institutions involved in the SARES project Principal investigator
Institution
Canada
Serge Demers Louis Fortier
Institut Maurice-Lamontagne, Mont-Joli, Que. Universiti Laval, Qu&bec,QuC.
Michel Gosselin I?ric Hudier R. Grant Ingram
Universite du Quebec g Rimouski, Rimouski, Qt.6 UniversitC du Quebec B Rimouski, Rimouski, QuC. McGill University, Montrt!al, QuC.
Kim Juniper Louis Legendre Maurice Levasseur Richard F . Marsden RsrlphE. H. Smith Jean-Claude Therriault Alain F. VCzina
Universiti du QuCbec 5 Montreal, Mont&al, Que. Universite Lavai, Qdbec, QuC. Institut Maurice-Lamontagne, Mont-Joli, QuC. Royal Roads Military College, Victoria, B.C. University of Waterloo, Waterloo, Ont. Institut Maurice-Lamontagne, Mont-Joli, QuC. Institut Maurice-Lamontagne, Mont-Joli, Qu6.
Japan
Masaaki Aota Yoshihiro Fujiyoshi Mitsuo Fukuchi Hiroshi Hattori Takao Hoshiai Motoaki Kishino Sakae Kudoh Ren Kuwabara Isamu Matsuda Yasuhiko Naito Tsuneo Nishiyama Hiroaki Saitoh Hiroo Satoh Kunio Shirasawa Satoru Taguchi Masayuki Takahashi Shuhei Takahashi Yukuyu Yamrrguchi
Sea Ice Research Laboratory, Univ. Hokkaido, Mombetsu Saroma Research Center of Aquaculture, Tokoro National Institute of Polar Research, Tokyo Hokkaido Tokai University, Sapporo National Institute of Polar Research, Tokyo The Institute of Physical and Chemical Research, Saitama National Institute of Polar Research, Tokyo Tokyo University of Agriculture, Abashiri Hiroshima University, Hiroshima National Institute of Polar Research. Tokyo Hokkaido Tokai University, Sapporo Hokkaido National Fisheries Institute, Kushiro Tokyo University of Fisheries, Tokyo Sea Ice Research Laboratory, Univ. Hokkaido, Mombetsu Hokkaido National Fisheries Institute, Kushiro University of Tokyo, Tokyo Kitami Institute of Technology, Kitami Saitama University, Saitama
1.1. The Canada-Japan Agreement on Cooperation in Science and Technology
In May 1986, the prime ministers of Canada and Japan signed an Agreement on Cooperation in Science and Technology in Tokyo. To implement this agreement, the two countries conducted a joint study for enhanced cooperation in the field of science and technology in 1988 and 1989. This led to the publication of the Canada-Japan Complementarity Study (Kenney-Wallace, 1989). The study recommended a program of enhanced cooperation in six broad “umbrella” areas of science and technology, i.e.: advanced materials and biomaterials; biotechnology
and biosciences; oceanography and ocean engineering; space science, technology and cosmology; advanced manufacturing, microelectronics, communications and photonics; and sustainable development and environmental management. Within the umbrella area of sustainable development and environmental management, it was recommended that the following key preferred areas be singled out for immediate attention: acidification processes; environmental effects of acidification; and engineering solutions; the influence of the North Polar Region on global climatic change and global scale simulation; atmospheric trace gases dispersion; and environmental observation from space.
1.2.
e SA
reject
tional Scientific
Fig. 1. Map showing the maximum extent of sea ice in the Northern Hemisphere and the position of the two SARES sampling sites (after Shirasawa and Ingram, 19951.
The study recommended the organization of binational topical workshops, conferences, and meetings in selected umbrella areas. As a consequence, a Japan-Canada workshop concerning the in..uence of the North Polar Region on global climatic change and global-scale simulation was held in Tokyo and Tsukuba, Japan, in arch 1990. Discussions were in four areas: global warming phenomena in the Arctic; solar energy and polar upper atmosphere; the role of the Arctic cryosphere and its evolution; and changes in the Arctic atmosphere including the ozone layer, surface ozone and Arctic haze. Concerning gbbal warming phenomena in the Arctic, the topics identified for collaborative research were the role of the Arctic Ocean on global climate change, polar meteorology, biological evidence of global change and technologies for Arctic research. As to the role of the Arctic Ocean on global climate change, the report of the workshop stressed that “there is a great deal of interest in the role of the oceans on global climate change but very little of this is focused upon the Arctic Basin. A key issue remains the role of the Arctic Ocean (or at least its marginal seas) as a CO2 sink. Of interest are key processes involving ice physics, hydrodynamics, and biological production’’.
e e anthropogenic increase in atmospheric carbon dioxide is believed to be responsible for about half the potential global warming of the earth (Ramanathan et al., 1985). It has been estimated that about half the CO, released since the beginning of the industrial era may have been absorbed by the oceans (Sundqvist, 1985). Carbon dioxide trarrsfetred into the deep oceanic waters is effectively removed from the atmosphere for centuries (i.e., sequestered), thus reducing the magnitude of global warming. Carbon dioxide enters the upper ocean by gas exchange across the air-sea interface or as dissolved compounds in river waters. CO, can be transferred to deep waters by two general pathways: the transport of dissolved inorganic and organic carbon by deep convection (i.e., “solubility pump”); and the sinking of biogenic particles from the surface into the deep sea. Except in the immediate areas of deep-water formation, the second pathway is orders of magnitude faster than the first (days/weeks versus decades/centuries; see Legendre and Gosselin, 1989). Close to the surface (euphotic zone), solar
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M. Fukuchi et al. /Journal of Marine Systms 1 I (1997) 1-S
light fuels the photosynthetic incorporation of inorgalric carbon into organic molecules by microalgae, of which a fraction sinks out to deep waters (as intact cells, faecal pellets and marine snow; e.g., Legendre and Le Fevre, 1989) or is actively transported by vertically migrating organisms (e.g., Longhurst et al., 1990). This export pathway is CO, pump” or “soft known as the “biological tissue pump’’; a third export mechanism is the ‘‘carbonate pump”, i.e., sedimentation of biogenic calcium carbonate (Volk and Hoffert, 1985). However, the quantitative importance of the biological CO* pump for the actual sequestration of anthropogenic CO, remains an open debate (e.g., Broecker, 1991; Longhurst, 1991; Falkowski and Wilson, 1992; Raven, 1993; Riebesell et al., 1993). The Arctic Ocean is potentially very sensitive to global climate change. For example, climate models suggest that global warming could bring a reduction in the extent of the sea ice (e.g., Manak and Mysak, 1989). According to Anderson et al. ( 1990), the upper layers of the Arctic Ocean are the site of active biological pumping of atmospheric CO, for which they provide a sink. However, there is little penetration of this CO, into the deep waters. This does not imply that all the CO, dissolved in Arctic sea waters is transported back to the atmosphere: it could be fixed back into organic particles by high local production in waters that leave the Arctic Ocean (mainly through Fram Strait and also through the Canadian Archipelago) and be thus partly exported to depth. In the Arctic Ocean, phytoplankton production is three times higher over the shelves (< 200 m) than offshore (27 versus 9 g Cm-* yr- ‘; Subba Rao and Platt, 1984). In addition, the seasonal first-year ice, which is mainly located over the shelves, supports microalgal production estimated to be ca. 10 g Cm-” yr-’ on average and would thus account for ca. 25% of the annual total primary production in the Arctic Ocean north of 65” latitude (Legendre et al., 1992). This figure does not take into account marginal seas such-as Hudson Bay, the Labrador Sea, or the Okhotsk Sea, where first-year ice is the rule. In spring and early summer, concentrations of algae are generally higher by orders of magnitude in the bottom few centimetres of the ice sheet than above (e.g., table 1 in Demers et al., 1986). As mentioned above, only part of the microalgal
production is exported to depth. As a general rule, Legendre and Le Fevre ( 1989) have proposed that export increases with the size of primary producers. This has been documented by in situ measurements in a tropical neritic ecosystem (Hopcroft et il., 1990). Since large-sized microalgae (e.g., > 2-5 pm) dominate the biomass in first-year ice areas, significant export may be expected. Mechanisms affecting the export of microalgal carbon include grazing by large planktonic herbivores followed by active downward transport of respiratory CO,, consumption and in situ respiration by the microbial food web, and sedimentation of intact cells and faecal pellets. These have been reviewed by Legendre et al. ( 1992) for both Arctic and Antarctic waters. Assessing the significance of the biological CO, pump under the first-year ice of the Arctic Ocean and of its marginal seas thus requires a multidisciplinary approach. This was the approach of the SAKS project.
3. Research plan The general approach of the SARES project was to draw on the complementary expertise of Canadizln and Japanese researchers with the aim of measuring the activity of the biological CO, pump under the first-year sea ice and characterizing its main physical controls. To derive conclusions of general applicability, the stud \I compared two first-year ice areas with very contra Gng characteristics (Table 2). Saroma-ko is a coast;rl lagoon located in Northern Hokkaido (44”N). It is the southernmost area in the Northern Hemisphere with seasonal sea ice. The lagoon is shallow (ca. 10 m depth) and velocities of under-ice currents are generally low (4-5 cm s - ’). Because of the latitude and relatively thin ice (< 50 cm), the bottom part of the ice is well illuminated as early as February, which determines the beginning of the growth season for ice algae. During growth, ice algae and phytoplankton in the under-ice water column are subjected to a day-night light cycle. Most of the accumulated algal biomass is flushed into the water column in March, at the time of ice melt. In contrast, Resolute Passage is an area with free water circulation located in the Canadian High Arctic (74”N). It is one of the northernmost areas with recurrent first-year sea ice (there are patches of
. ~~~lfC~1~ et trl. / Jourr?al of”
5
Table 2 Some contrasting characteristics Of t and Resolute Passage (Northwest Territories, Canadian
Latitude Geography First-year sea ice (Northern Hemisphere) Water depth Ice thickness Under-ice currents Growth season of ice algae Solar irradiance during the study
aido, Japan, 44”06.87’N, 14336.98’E) Saroma-ko Lagoon
Resolute Passage
44”N coastal lagoon southernmost IOm <50cm low velocity February-March day-night
74 ‘IV open passage among the northerxnost
first-year ice everywhere in the Arctic tween fields of multi-year ice). The passage is relatively deep ( > 100 m) and under-ice tidal currents are strong (3-27 ems -’ 1. Because of the latitude and thick ice (II -2 m), irradiance in the ice bottom is not strong enough for algae to start growing before April. During their growth, algae are exposed to almost continuous illumination. Ice melt occurs in June and is accompanied by a large algal flux from the ice. It was hypothesized that such different characteristics would influence (1) the hydrodynamics of the under-ice water column and ice-water interface, (2) nutrient replenishment in the sea-ice environment, (3) the growth of algae in the ice and of phytoplankton in the water column, (4) the transfer of primary production to the herbivorous and microbial food webs, and (5) the sedimentation export of biogenic particles to depth. These variables determine the downward flux of biogenic carbon. Important objectives of the SARES project were to determine the role of the different biological compartments in the biogenic export of carbon dioxide under the first-year ice and to discriminate among the possible sources of nutrients that fuel the biological production and export. These tasks could be partly achieved by statistical analysis of field observations, but interpretations are always limited by simplifying assumptions and incompleteness of the data set. Modeling was thus required to alleviate these restrictions and to explore various scenarios. In addition to traditional ecosystem models, advances in numerical techniques have opened up the field of inverse methods, where unknown functional relationships can be computed directly from temporal or spatial series of observations (Enting, 1985). Inverse
1-2 m high velocity April-June almost 24 h
as recently been applied to anaionship between food web st d Platt, 1988), was us imate the source st 01s and different nu ply pathway; in biob,z;iic export.
After funding of the Japanese and Canadian posals by granting agencies, two workshops were organized to favour closer contacts between Canadian and Japanese participants and to discuss details of the science plan and its implementation. The first meeting was held at the National Institute of Polar Research (Tokyo, Japan, 28 January-l February 199l), during which nineteen Japanese and ten Canadian scientists examined the international, Japanese and Canadian contexts of the project, reviewed current activities of the participants and previous investigations in Saroma-ko Lagoon and Resolute Passage, and drew up general plans for the 1992 field work. The second workshop was held at Lava1 University (QuCbec City, Canada, 23-26 September 1991), during which fifteen Canadian and five Japanese participants discussed recent studies conducted at Resolute and Saroma-ko dnd completed detailed plans for the sampling and logistics of the two SARES field studies. Field work extended over more than four months in the winter and spring of 1992. The study in Saroma-ko Lagoon was from 18 February to 28 March while that in Resolute Passage was from 7 April to 30 June. Because of the short time between
6
M. Fukuchi et al. / Jourttal of Mnritw System 11 (1997) l-8
the two studies (i.e., less than two weeks), moving the large quantity of equipment and several participants between the two distant fold sites required detailed planning and a major logistic effort. Vatiables measured at the two study sites included meteorology, hydrodynamics in the under-ice water column and at the ice-water interface, production of algae in the ice bottom and water column and control by nutrient effects, dynamics of the microbial food web, production of zooplankton and grazing on algae, sedimentation of intact algae and faecal pellets, and production of ichthyoplankton. Specific aims of the various sets of measurements as well as methods are detailed in individual papers (this volume). Following the field studies, two workshops were dedicated to the joint analysis of data and preparation of publications. From 1 to 5 February 1993, ten Japanese and nine Canadian scientists held a workshop dedicated to the SARES project within the Eighth International Symposium on Okhotsk Sea and Sea Ice (Mombetsu, Hokkaido, Japan). During this meeting, results from field work were reviewed and joint publications and presentations were planned. From 27 September through 1 October 1993, sixteen Canadian and seven Japanese participants met at the Maurice Lamontagne Institute (Mont-Joli, Q&bec, Canada). The workshop was devoted to detailed planning of the present issue of the Journal of Marine Systems and actual writing of joint publications. Finally, during the Sixteenth Symposium on Polar Biology (National Institute of Polar Research, Tokyo, l-3 December 1993), there were 23 presentations (oral and posters) by Japanese and Canadian scientists on results of the SARES project.
5. Main achievements to date The SARES project has already produced a number of publications, data reports and presentations at meetings. Publications to date are those of Paquet (1999, Suzuki (1993), Laurion (1994), Levasseur et al. (1994), Mars&n et al. (1994a,b, 1995), Demers et al, (1995), Fortier et al. (1995), Hudier et al. (1995), Laurion et al. (1995) and Shirasawa and Ingram (1995). The data reports are from Shirasawa et al. (199% Taguchi et al. (1994) and Smith et al. (1995). Presentations at meetings included three papers at
the 1992 Arctic Science Workshop, Tokyo, Japan (Anon., 1992), 30 at the Eighth International Symposium on Okhotsk Sea and Sea Ice ( 1993), Mombetsu, Japan (Anon., 1993) 23 at the Sixteenth Symposium on Polar Biology (1993), Tokyo, Japan (Fukuchi and Kanda, 1995) and four at the 1994 Ocean Sciences Meeting, San Diego, USA (Anon., 1994). There were presentations at several other meetings, e.g., the Third Global Emiliana Modeling Workshop, Blagnac, France (1992). the Congress of the Canadian Meteorological and Oceanographic Society, Fredericton, N.B., Canada (1993), the AGU Fall Meeting, San Francisco, CA ( 1993) the 61st Congress of the Association canadienne-fraqaise pour 1‘avancewent des sciences, Rimouski, Que., Canada (1993), and the 33rd Annual Meeting of the Groupement des Protbtologues de Langue FranGaise,
Nice, France ( 1994). The present issue of the Journal of Marine Systems represents a major effort of publication, but it does not exhaust the wealth of data collected during the SARES project. Additional publications, in various professional journals, are thus expected in the coming years.
Acknowledgements In Japan, the main source of funding for the SARES project was a grant from the Monbusho International Scientific Research Program (03044 146) and grants-in-aid for scientific research. In addition, participants benefited from various research grants, such as the cooperative project of the National Institute of Polar Research and the Sukekawa Scientific Research Grant. Special thanks are extended to the Saroma Research Center of Aquaculture and the Hokkaido Tokoro Shounenshizen-no Iye in Tokoro for use of their facilities. In Canada, the main source of funding was a grant from the Japan Science and Technology Fund (JSTF; External Affairs and International Trade Canada). In addition, participants benefited from research grants from the Natural Sciences and Engineering Research Council of Canada (NSERC) and the Academic Research Program of the Department of National Defense of Canada, as well as a team grant from the Fonds FCAR of Qugbec. Infrastructureand logistic
Sedimefltat~oR in a tropical neritic ecosystem Jamaica. Cont. Shelf Res., 10: 795-806.
near
33: 569-580. Kenney-Wallace, G., 1989. Canada-Japan complementarity study.
Dr. Louis Fortier, Kudoh, Dr. Ralph sawa for leading various phases o Finally, we are very grateful to Therriault for his leadership in publication of the present volume and to Ms. Laure Devine for her major contribution to the edition of manuscripts.
Anderson, L.G., Dyrssen, D. and Jones, E.P., 1990. An assessment of the transport of atmospheric CO, into the Arctic Ocean. J. Geophys. Res., 95: 1703- 17 11. Anon., 1992. Arctic Science Workshop, Arctic Environment Research Center, Natl. Inst. Polar Res.. Tokyo, 102 pp. Anon., 1993. The Eighth International Symposium on Okhotsk Sea and Sea Ice and ISY/Polar Ice Extent Workshop, Okhotsk Sea and Cold Ocean Research Association, Mombetsu, 568 PP* Anon., 1994. 1994 Ocean Sciences Meeting. EOS, 75(3) Suppl., 250 pp. Broecker, W.S., 1991. Keeping global change honest. Global Biogeochem. Cycles, 5: 19 1- 192. Demers, S., Legendre, L., Therriault, J.-C. and Ingram, R.G., 1986. Biological production at the ice-water ergocline. In: J.C.J. Nihoul (Editor), Marine Interfaces Ecohydrodynamics. Elsevier, Amsterdam, pp. 3 l-54. Demers, S., Monfort, P., Laurion, I., Sime-Ngando, T., Robineau, B. and Fortier, L., 1995. The microbial food web: comparative study under first-year ice at low and high latitudes in the Northern Hemisphere. Proc. NJPR Symp. Polar. Biol., 8: 5-10. Enting, I.G., 1985. A classification of some inverse problems in
geochemical modelling. Tellus, 37B: 216-229. Falkowski, P.J. and Wilson, C., 1992. Phytoplankton productivity in the North Pacific ocean since 1900 and implications for absorption of anthropogenic 03,. Nature, 358: 741-743.
Sci. Count. Can., 22 pp. J 21kon. B.,1994. La boucle microbienne associk B la communaQe des algues de glace: biomasse et activite de predation des protozoaires dans le Passage de Resolute (Arctique canadiet& MSc. Thesis, Univ. du QuCbec B Rimouski, 65 pp. Laurion, I., Demers, S. and V&ina, A.F., 1995. The microbial food web associated with the ice algal assemblage: biomass and bacterivory of nanoflagellate protozoans in Resolute Bay (High Canadian Arctic). Mar. Ecol. Prog. Ser., 120: 77-87. Legendre, L. and Gosselin, M., 1989. Net production and export of organic matter to the deep ocean: consequences of some recent discoveries. Limnol. Oceanogr., 34: 1374- 1380. Legendre, L. and Le Fkvre, J., 1989. Hydrodynamical singularities as controls of recycled versus export production in oceans. In: W.H. Berger, V.S. Smetacek and G. Wefer (Editors), Productivity of the Ocean: Present and Past. Wiley, Chichester, pp. 49-63. Legendre, L., Ackley. S.F., Dieckmann, G.S., Gulliksen, B., omer, g., Hoshiai, T., Mehtikov, LA., Reeburgh, W.S., Spindler. M. and Sullivan, C.W., 1992. Ecology of Sea Ice Biota. 2. Global significance. Polar Biol., 12: 429-444. Levasseur, M., Gosselin. M. and Michaud, S., 1994. A new source of dimethylsulfide (DMS) for the Arctic atmosphere: ice diatoms, Mar. Biol., 121: 381-387. Longhurst, A.R., 1991. Role of the marine biosphere in the global carbon cycle. Limnol. Oceanogr., 36: 1507- 1526. Longhurst, A.R., Bedo, A.W., Harrison, W.G., Head, E.J.H. and Sameoto, D.V., 1990. Vertical flux of respiratory carbon by oceanic die1 migrant biota. Deep-Sea Res., 37: 685-694. Manak, D.K. and Mysak, L.A., 1989. On the relationship between Arctic sea ice anomalies and fluctuations in northern Canadian air temperature and river discharge. Atmos. Ocean, 27: 68% 691. Marsden, R.F., Ingram, R.G. and Legendre, L., 1994a. Currents under land-fast ice in the Canadian Arctic Archipelago Part 2: Vertical mixing. J. Mar. Res., 52: 1037-1049. Marsden, R.F., Paquet, J.R. and Ingram, R.G., 1994b. Currents under land-fast ice in the Canadian Arctic Archipelago Part 1. Vertical velocities. J. Mar. Res., 52: 1017-1036. Marsden, R.F.. Juszko, B.A. and Ingram, R.G., 1995. Jntemal wave directional spectra using an acoustic Doppler current profiler. J. Geophys. Res., loo(C8): 16,179-16,192. Paquet, JR., 1993. Internal solitary waves with acoustic applica-
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tions to the Canadian Arctic and the Scotian Shelf. M.Sc. Thesis, Phys. Dep., Royal Roads Military College, Victoria, B.C., 88 pp. Ramanathan, V., Cicerone, R.J., Singh, H.B. and Kiehl, J.T., 1985. Trace gas trends and their potential role in climatic change. J. Geophys. Res., 90: 5547-5566. Raven, J.A., 1993. Limits on growth rates. Nature, 361: 209-210. Riebesell, U., Wolf-Gladrow. D.A. and Smetacek, V., 1993. Carbon dioxide limitation of marine phytoplankton growth rates. Nature, 36 1: 249-25 1. Shirasawa, K. and Ingram, R.G., 1995. Comparative study of oceanographic characteristics above/under first-year sea ice at low and high latitudes. Proc. NIPR Symp. Polar. Biol., 8: 20-28. Shirasawa, K., Ikeda. M., Takatsuka, T., Ishikawa, M., Aota, M., Ingram, G.. Belanger, C., Peltola, P.. Takahashi, S., Matsuyama, M., Hudier, E., Fujiyoshi, Y., Kodama, Y. and Ishikawa. N., 1993. Atmospheric and Oceanographic Data Report for Saroma-ko Lagoon of the SARES (Saroma-Resolute Studies) Project, 1992. Low Temp. Sci. Ser. A, Data Rep. 52, 167 pp. Smith, R.E.H., Demers, S., Hattori, H., Kudoh. S., Legendre, L., Michel, C., Gosselin, M., Robineau, B., Suzuki, Y., Takahashi, M., Therriault, J.C., Juniper, S.K. and Sime-Ngando, T., 1995. Biological and chemical investigations of the SaromaResolute project in ice-covered Resolute Passage, 1392. Can. Data Rep. Hydrogr. Ocean Sci. 137, 19 pp.
Subba Rao, D.V. and Platt, T., 1984. Primary production of Arctic waters. Polar Biol.. 3: 191-20 1. Sundqvist, E.T., 1985. Geological perspectives on carbon dioxide and the carbon cycle. In: E.T. Sundqvist and W.S. Broecker (Editors), The Carbon Cycle and Atmospheric CO,: Natural Variations Archean to Present. AGU Monogr., 32: 5-59. Suzuki, Y., 1993. Adaptive growth responses of several diatom species to the temperature determined by the physiological characteristics of photosyqt$esis and respiration. Ph.D. Thesis, Univ. Tokyo, 91 pp. Taguchi, S., Demers, S., Fortier, L., Fortier, M., Fujiyoshi, Y., Hattori, H., Kasai, H., Kishino, M., Kudoh, S., Legendre, L.. McGiness, F., Michel, C., Sime-Ngando, T., Robineau, B., Saito, H., Suzuki, Y., Takahashi, M., Therriault, J.-C., Aota, M., Ikeda, M., Ishikawa, M.. Takatsuka, T. and Shirasawa, K., 1994. Biological data report for the Saroma-ko site of the SARES (Saroma-Resolute Studies) Project, February-March, 1992. Low Temp. Sci. Ser. A. Data Rep. 53, 163 pp. VCzina, A.F. and Platt, T., 1988. Food-web dynamics in the ocean. 1. Best-estimates of flow networks using inverse methods. Mar. Ecol. Prog. Ser., 42: 269-287. Volk, T. and Hoffert, M.I., 1985. Ocean carbon pumps: Analysis of relative strengths and efficiencies in ocean driven CO, changes. In: E.T. Sundqvist and W.S. Broecker (Editors), The Carbon Cycle and Atmospheric CO, : Natural Variations Archean to Present. AGU Monogr., 32: 99-l 10.
a a
Department of Polar Biology, National Institute of Polar Research. 9-10, Saga I-Chome, ltabmhi-ku, Tokyo 173. Japan b Df!partement de biologie. Universite’Lural. Quibec. Qut!. GIK 7P4. Canada Received 14 October 1994; accepted 7 July 1995
Abstract A joint Canada-Japan project was conducted on the first-year ice of Saroma-ko Lagoon (northern do, Japan) and Resolute Passage (Northwest Territories, Canada) during the winter and spring of 1992. Objectives of the SARES project were to (1) measure the activity of the biological CO, pump under the first-year sea ice and (2) characterize its main physical controls. The two study sites exhibit contrasting characteristics. Among others, Saroma-ko southernmost area in the Northern Hemisphere with seasonal sea ice whereas Resolute Passage is one of t areas with recurrent first-year sea ice. It was hypothesized that such different characteristics would influence variables that determine the downward flux of biogenic carbon, e.g., hydrodynamics, nutrient replenishment, growth of ice algae and phytoplankton, transfer of primary production to the herbivorous and microbial webs, and sedimentation of biogenic particles. Mea!.ured variables included meteorology, hydrodynamics, prim&at-yproduction and nutrient effects, microbial web dynamics, production and grazing of zooplankton and ichthyoplankton, and sedimentation of algae and faecal pellets. The project involved 30 Canadian and 25 Japanese scientists, graduate students and technicians from seven institutions in Canada and twelve in Japan. Keywords: Arctic, first year sea Ice, biological CO, pump
1. Historical A joint Canada-Japan project was conducted on the first-year ice of Saroma-ko Lagoon (Northern Hokkaido, Japan) and Resolute Passage (Northwest
* Corresponding author. Phone: 81 3 3962 603 1. Fax: 81 3 3962 5743. E-mail: [email protected]. ’M. Fukuchi and L. Legendre are the coordinators of the SARES project.
Territories, Canada) during the winter and spring of 1992 (Fig. I). Overall, 30 Canadian and 25 Japanese scientists, graduate students and technicians from seven institutions in Canada and twelve in Japan participated in the planning of the SARES (Saroma-Resolute) project and field expeditions as well as the subsequent data analyses (Table 1). This major oceanographic venture was within the framework of the Canada-Japan Agreement on Cooperation in Science and Technology.
0924-7963/97/$17.00 Copyright 0 1997 Elsevier Science B.V. All rights reserved. PII SO924-7963(96)00022-X
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M. F~k~cki et al. / Jownal of Marine System I I (1997) l-8
Table 1 Principal investigators and institutions involved in the SARES project Principal investigator
Institution
Canada
Serge Demers Louis Fortier
Institut Maurice-Lamontagne, Mont-Joli, Que. Universiti Laval, Qu&bec,QuC.
Michel Gosselin I?ric Hudier R. Grant Ingram
Universite du Quebec g Rimouski, Rimouski, Qt.6 UniversitC du Quebec B Rimouski, Rimouski, QuC. McGill University, Montrt!al, QuC.
Kim Juniper Louis Legendre Maurice Levasseur Richard F . Marsden RsrlphE. H. Smith Jean-Claude Therriault Alain F. VCzina
Universiti du QuCbec 5 Montreal, Mont&al, Que. Universite Lavai, Qdbec, QuC. Institut Maurice-Lamontagne, Mont-Joli, QuC. Royal Roads Military College, Victoria, B.C. University of Waterloo, Waterloo, Ont. Institut Maurice-Lamontagne, Mont-Joli, QuC. Institut Maurice-Lamontagne, Mont-Joli, Qu6.
Japan
Masaaki Aota Yoshihiro Fujiyoshi Mitsuo Fukuchi Hiroshi Hattori Takao Hoshiai Motoaki Kishino Sakae Kudoh Ren Kuwabara Isamu Matsuda Yasuhiko Naito Tsuneo Nishiyama Hiroaki Saitoh Hiroo Satoh Kunio Shirasawa Satoru Taguchi Masayuki Takahashi Shuhei Takahashi Yukuyu Yamrrguchi
Sea Ice Research Laboratory, Univ. Hokkaido, Mombetsu Saroma Research Center of Aquaculture, Tokoro National Institute of Polar Research, Tokyo Hokkaido Tokai University, Sapporo National Institute of Polar Research, Tokyo The Institute of Physical and Chemical Research, Saitama National Institute of Polar Research, Tokyo Tokyo University of Agriculture, Abashiri Hiroshima University, Hiroshima National Institute of Polar Research. Tokyo Hokkaido Tokai University, Sapporo Hokkaido National Fisheries Institute, Kushiro Tokyo University of Fisheries, Tokyo Sea Ice Research Laboratory, Univ. Hokkaido, Mombetsu Hokkaido National Fisheries Institute, Kushiro University of Tokyo, Tokyo Kitami Institute of Technology, Kitami Saitama University, Saitama
1.1. The Canada-Japan Agreement on Cooperation in Science and Technology
In May 1986, the prime ministers of Canada and Japan signed an Agreement on Cooperation in Science and Technology in Tokyo. To implement this agreement, the two countries conducted a joint study for enhanced cooperation in the field of science and technology in 1988 and 1989. This led to the publication of the Canada-Japan Complementarity Study (Kenney-Wallace, 1989). The study recommended a program of enhanced cooperation in six broad “umbrella” areas of science and technology, i.e.: advanced materials and biomaterials; biotechnology
and biosciences; oceanography and ocean engineering; space science, technology and cosmology; advanced manufacturing, microelectronics, communications and photonics; and sustainable development and environmental management. Within the umbrella area of sustainable development and environmental management, it was recommended that the following key preferred areas be singled out for immediate attention: acidification processes; environmental effects of acidification; and engineering solutions; the influence of the North Polar Region on global climatic change and global scale simulation; atmospheric trace gases dispersion; and environmental observation from space.
1.2.
e SA
reject
tional Scientific
Fig. 1. Map showing the maximum extent of sea ice in the Northern Hemisphere and the position of the two SARES sampling sites (after Shirasawa and Ingram, 19951.
The study recommended the organization of binational topical workshops, conferences, and meetings in selected umbrella areas. As a consequence, a Japan-Canada workshop concerning the in..uence of the North Polar Region on global climatic change and global-scale simulation was held in Tokyo and Tsukuba, Japan, in arch 1990. Discussions were in four areas: global warming phenomena in the Arctic; solar energy and polar upper atmosphere; the role of the Arctic cryosphere and its evolution; and changes in the Arctic atmosphere including the ozone layer, surface ozone and Arctic haze. Concerning gbbal warming phenomena in the Arctic, the topics identified for collaborative research were the role of the Arctic Ocean on global climate change, polar meteorology, biological evidence of global change and technologies for Arctic research. As to the role of the Arctic Ocean on global climate change, the report of the workshop stressed that “there is a great deal of interest in the role of the oceans on global climate change but very little of this is focused upon the Arctic Basin. A key issue remains the role of the Arctic Ocean (or at least its marginal seas) as a CO2 sink. Of interest are key processes involving ice physics, hydrodynamics, and biological production’’.
e e anthropogenic increase in atmospheric carbon dioxide is believed to be responsible for about half the potential global warming of the earth (Ramanathan et al., 1985). It has been estimated that about half the CO, released since the beginning of the industrial era may have been absorbed by the oceans (Sundqvist, 1985). Carbon dioxide trarrsfetred into the deep oceanic waters is effectively removed from the atmosphere for centuries (i.e., sequestered), thus reducing the magnitude of global warming. Carbon dioxide enters the upper ocean by gas exchange across the air-sea interface or as dissolved compounds in river waters. CO, can be transferred to deep waters by two general pathways: the transport of dissolved inorganic and organic carbon by deep convection (i.e., “solubility pump”); and the sinking of biogenic particles from the surface into the deep sea. Except in the immediate areas of deep-water formation, the second pathway is orders of magnitude faster than the first (days/weeks versus decades/centuries; see Legendre and Gosselin, 1989). Close to the surface (euphotic zone), solar
4
M. Fukuchi et al. /Journal of Marine Systms 1 I (1997) 1-S
light fuels the photosynthetic incorporation of inorgalric carbon into organic molecules by microalgae, of which a fraction sinks out to deep waters (as intact cells, faecal pellets and marine snow; e.g., Legendre and Le Fevre, 1989) or is actively transported by vertically migrating organisms (e.g., Longhurst et al., 1990). This export pathway is CO, pump” or “soft known as the “biological tissue pump’’; a third export mechanism is the ‘‘carbonate pump”, i.e., sedimentation of biogenic calcium carbonate (Volk and Hoffert, 1985). However, the quantitative importance of the biological CO* pump for the actual sequestration of anthropogenic CO, remains an open debate (e.g., Broecker, 1991; Longhurst, 1991; Falkowski and Wilson, 1992; Raven, 1993; Riebesell et al., 1993). The Arctic Ocean is potentially very sensitive to global climate change. For example, climate models suggest that global warming could bring a reduction in the extent of the sea ice (e.g., Manak and Mysak, 1989). According to Anderson et al. ( 1990), the upper layers of the Arctic Ocean are the site of active biological pumping of atmospheric CO, for which they provide a sink. However, there is little penetration of this CO, into the deep waters. This does not imply that all the CO, dissolved in Arctic sea waters is transported back to the atmosphere: it could be fixed back into organic particles by high local production in waters that leave the Arctic Ocean (mainly through Fram Strait and also through the Canadian Archipelago) and be thus partly exported to depth. In the Arctic Ocean, phytoplankton production is three times higher over the shelves (< 200 m) than offshore (27 versus 9 g Cm-* yr- ‘; Subba Rao and Platt, 1984). In addition, the seasonal first-year ice, which is mainly located over the shelves, supports microalgal production estimated to be ca. 10 g Cm-” yr-’ on average and would thus account for ca. 25% of the annual total primary production in the Arctic Ocean north of 65” latitude (Legendre et al., 1992). This figure does not take into account marginal seas such-as Hudson Bay, the Labrador Sea, or the Okhotsk Sea, where first-year ice is the rule. In spring and early summer, concentrations of algae are generally higher by orders of magnitude in the bottom few centimetres of the ice sheet than above (e.g., table 1 in Demers et al., 1986). As mentioned above, only part of the microalgal
production is exported to depth. As a general rule, Legendre and Le Fevre ( 1989) have proposed that export increases with the size of primary producers. This has been documented by in situ measurements in a tropical neritic ecosystem (Hopcroft et il., 1990). Since large-sized microalgae (e.g., > 2-5 pm) dominate the biomass in first-year ice areas, significant export may be expected. Mechanisms affecting the export of microalgal carbon include grazing by large planktonic herbivores followed by active downward transport of respiratory CO,, consumption and in situ respiration by the microbial food web, and sedimentation of intact cells and faecal pellets. These have been reviewed by Legendre et al. ( 1992) for both Arctic and Antarctic waters. Assessing the significance of the biological CO, pump under the first-year ice of the Arctic Ocean and of its marginal seas thus requires a multidisciplinary approach. This was the approach of the SAKS project.
3. Research plan The general approach of the SARES project was to draw on the complementary expertise of Canadizln and Japanese researchers with the aim of measuring the activity of the biological CO, pump under the first-year sea ice and characterizing its main physical controls. To derive conclusions of general applicability, the stud \I compared two first-year ice areas with very contra Gng characteristics (Table 2). Saroma-ko is a coast;rl lagoon located in Northern Hokkaido (44”N). It is the southernmost area in the Northern Hemisphere with seasonal sea ice. The lagoon is shallow (ca. 10 m depth) and velocities of under-ice currents are generally low (4-5 cm s - ’). Because of the latitude and relatively thin ice (< 50 cm), the bottom part of the ice is well illuminated as early as February, which determines the beginning of the growth season for ice algae. During growth, ice algae and phytoplankton in the under-ice water column are subjected to a day-night light cycle. Most of the accumulated algal biomass is flushed into the water column in March, at the time of ice melt. In contrast, Resolute Passage is an area with free water circulation located in the Canadian High Arctic (74”N). It is one of the northernmost areas with recurrent first-year sea ice (there are patches of
. ~~~lfC~1~ et trl. / Jourr?al of”
5
Table 2 Some contrasting characteristics Of t and Resolute Passage (Northwest Territories, Canadian
Latitude Geography First-year sea ice (Northern Hemisphere) Water depth Ice thickness Under-ice currents Growth season of ice algae Solar irradiance during the study
aido, Japan, 44”06.87’N, 14336.98’E) Saroma-ko Lagoon
Resolute Passage
44”N coastal lagoon southernmost IOm <50cm low velocity February-March day-night
74 ‘IV open passage among the northerxnost
first-year ice everywhere in the Arctic tween fields of multi-year ice). The passage is relatively deep ( > 100 m) and under-ice tidal currents are strong (3-27 ems -’ 1. Because of the latitude and thick ice (II -2 m), irradiance in the ice bottom is not strong enough for algae to start growing before April. During their growth, algae are exposed to almost continuous illumination. Ice melt occurs in June and is accompanied by a large algal flux from the ice. It was hypothesized that such different characteristics would influence (1) the hydrodynamics of the under-ice water column and ice-water interface, (2) nutrient replenishment in the sea-ice environment, (3) the growth of algae in the ice and of phytoplankton in the water column, (4) the transfer of primary production to the herbivorous and microbial food webs, and (5) the sedimentation export of biogenic particles to depth. These variables determine the downward flux of biogenic carbon. Important objectives of the SARES project were to determine the role of the different biological compartments in the biogenic export of carbon dioxide under the first-year ice and to discriminate among the possible sources of nutrients that fuel the biological production and export. These tasks could be partly achieved by statistical analysis of field observations, but interpretations are always limited by simplifying assumptions and incompleteness of the data set. Modeling was thus required to alleviate these restrictions and to explore various scenarios. In addition to traditional ecosystem models, advances in numerical techniques have opened up the field of inverse methods, where unknown functional relationships can be computed directly from temporal or spatial series of observations (Enting, 1985). Inverse
1-2 m high velocity April-June almost 24 h
as recently been applied to anaionship between food web st d Platt, 1988), was us imate the source st 01s and different nu ply pathway; in biob,z;iic export.
After funding of the Japanese and Canadian posals by granting agencies, two workshops were organized to favour closer contacts between Canadian and Japanese participants and to discuss details of the science plan and its implementation. The first meeting was held at the National Institute of Polar Research (Tokyo, Japan, 28 January-l February 199l), during which nineteen Japanese and ten Canadian scientists examined the international, Japanese and Canadian contexts of the project, reviewed current activities of the participants and previous investigations in Saroma-ko Lagoon and Resolute Passage, and drew up general plans for the 1992 field work. The second workshop was held at Lava1 University (QuCbec City, Canada, 23-26 September 1991), during which fifteen Canadian and five Japanese participants discussed recent studies conducted at Resolute and Saroma-ko dnd completed detailed plans for the sampling and logistics of the two SARES field studies. Field work extended over more than four months in the winter and spring of 1992. The study in Saroma-ko Lagoon was from 18 February to 28 March while that in Resolute Passage was from 7 April to 30 June. Because of the short time between
6
M. Fukuchi et al. / Jourttal of Mnritw System 11 (1997) l-8
the two studies (i.e., less than two weeks), moving the large quantity of equipment and several participants between the two distant fold sites required detailed planning and a major logistic effort. Vatiables measured at the two study sites included meteorology, hydrodynamics in the under-ice water column and at the ice-water interface, production of algae in the ice bottom and water column and control by nutrient effects, dynamics of the microbial food web, production of zooplankton and grazing on algae, sedimentation of intact algae and faecal pellets, and production of ichthyoplankton. Specific aims of the various sets of measurements as well as methods are detailed in individual papers (this volume). Following the field studies, two workshops were dedicated to the joint analysis of data and preparation of publications. From 1 to 5 February 1993, ten Japanese and nine Canadian scientists held a workshop dedicated to the SARES project within the Eighth International Symposium on Okhotsk Sea and Sea Ice (Mombetsu, Hokkaido, Japan). During this meeting, results from field work were reviewed and joint publications and presentations were planned. From 27 September through 1 October 1993, sixteen Canadian and seven Japanese participants met at the Maurice Lamontagne Institute (Mont-Joli, Q&bec, Canada). The workshop was devoted to detailed planning of the present issue of the Journal of Marine Systems and actual writing of joint publications. Finally, during the Sixteenth Symposium on Polar Biology (National Institute of Polar Research, Tokyo, l-3 December 1993), there were 23 presentations (oral and posters) by Japanese and Canadian scientists on results of the SARES project.
5. Main achievements to date The SARES project has already produced a number of publications, data reports and presentations at meetings. Publications to date are those of Paquet (1999, Suzuki (1993), Laurion (1994), Levasseur et al. (1994), Mars&n et al. (1994a,b, 1995), Demers et al, (1995), Fortier et al. (1995), Hudier et al. (1995), Laurion et al. (1995) and Shirasawa and Ingram (1995). The data reports are from Shirasawa et al. (199% Taguchi et al. (1994) and Smith et al. (1995). Presentations at meetings included three papers at
the 1992 Arctic Science Workshop, Tokyo, Japan (Anon., 1992), 30 at the Eighth International Symposium on Okhotsk Sea and Sea Ice ( 1993), Mombetsu, Japan (Anon., 1993) 23 at the Sixteenth Symposium on Polar Biology (1993), Tokyo, Japan (Fukuchi and Kanda, 1995) and four at the 1994 Ocean Sciences Meeting, San Diego, USA (Anon., 1994). There were presentations at several other meetings, e.g., the Third Global Emiliana Modeling Workshop, Blagnac, France (1992). the Congress of the Canadian Meteorological and Oceanographic Society, Fredericton, N.B., Canada (1993), the AGU Fall Meeting, San Francisco, CA ( 1993) the 61st Congress of the Association canadienne-fraqaise pour 1‘avancewent des sciences, Rimouski, Que., Canada (1993), and the 33rd Annual Meeting of the Groupement des Protbtologues de Langue FranGaise,
Nice, France ( 1994). The present issue of the Journal of Marine Systems represents a major effort of publication, but it does not exhaust the wealth of data collected during the SARES project. Additional publications, in various professional journals, are thus expected in the coming years.
Acknowledgements In Japan, the main source of funding for the SARES project was a grant from the Monbusho International Scientific Research Program (03044 146) and grants-in-aid for scientific research. In addition, participants benefited from various research grants, such as the cooperative project of the National Institute of Polar Research and the Sukekawa Scientific Research Grant. Special thanks are extended to the Saroma Research Center of Aquaculture and the Hokkaido Tokoro Shounenshizen-no Iye in Tokoro for use of their facilities. In Canada, the main source of funding was a grant from the Japan Science and Technology Fund (JSTF; External Affairs and International Trade Canada). In addition, participants benefited from research grants from the Natural Sciences and Engineering Research Council of Canada (NSERC) and the Academic Research Program of the Department of National Defense of Canada, as well as a team grant from the Fonds FCAR of Qugbec. Infrastructureand logistic
Sedimefltat~oR in a tropical neritic ecosystem Jamaica. Cont. Shelf Res., 10: 795-806.
near
33: 569-580. Kenney-Wallace, G., 1989. Canada-Japan complementarity study.
Dr. Louis Fortier, Kudoh, Dr. Ralph sawa for leading various phases o Finally, we are very grateful to Therriault for his leadership in publication of the present volume and to Ms. Laure Devine for her major contribution to the edition of manuscripts.
Anderson, L.G., Dyrssen, D. and Jones, E.P., 1990. An assessment of the transport of atmospheric CO, into the Arctic Ocean. J. Geophys. Res., 95: 1703- 17 11. Anon., 1992. Arctic Science Workshop, Arctic Environment Research Center, Natl. Inst. Polar Res.. Tokyo, 102 pp. Anon., 1993. The Eighth International Symposium on Okhotsk Sea and Sea Ice and ISY/Polar Ice Extent Workshop, Okhotsk Sea and Cold Ocean Research Association, Mombetsu, 568 PP* Anon., 1994. 1994 Ocean Sciences Meeting. EOS, 75(3) Suppl., 250 pp. Broecker, W.S., 1991. Keeping global change honest. Global Biogeochem. Cycles, 5: 19 1- 192. Demers, S., Legendre, L., Therriault, J.-C. and Ingram, R.G., 1986. Biological production at the ice-water ergocline. In: J.C.J. Nihoul (Editor), Marine Interfaces Ecohydrodynamics. Elsevier, Amsterdam, pp. 3 l-54. Demers, S., Monfort, P., Laurion, I., Sime-Ngando, T., Robineau, B. and Fortier, L., 1995. The microbial food web: comparative study under first-year ice at low and high latitudes in the Northern Hemisphere. Proc. NJPR Symp. Polar. Biol., 8: 5-10. Enting, I.G., 1985. A classification of some inverse problems in
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Sci. Count. Can., 22 pp. J 21kon. B.,1994. La boucle microbienne associk B la communaQe des algues de glace: biomasse et activite de predation des protozoaires dans le Passage de Resolute (Arctique canadiet& MSc. Thesis, Univ. du QuCbec B Rimouski, 65 pp. Laurion, I., Demers, S. and V&ina, A.F., 1995. The microbial food web associated with the ice algal assemblage: biomass and bacterivory of nanoflagellate protozoans in Resolute Bay (High Canadian Arctic). Mar. Ecol. Prog. Ser., 120: 77-87. Legendre, L. and Gosselin, M., 1989. Net production and export of organic matter to the deep ocean: consequences of some recent discoveries. Limnol. Oceanogr., 34: 1374- 1380. Legendre, L. and Le Fkvre, J., 1989. Hydrodynamical singularities as controls of recycled versus export production in oceans. In: W.H. Berger, V.S. Smetacek and G. Wefer (Editors), Productivity of the Ocean: Present and Past. Wiley, Chichester, pp. 49-63. Legendre, L., Ackley. S.F., Dieckmann, G.S., Gulliksen, B., omer, g., Hoshiai, T., Mehtikov, LA., Reeburgh, W.S., Spindler. M. and Sullivan, C.W., 1992. Ecology of Sea Ice Biota. 2. Global significance. Polar Biol., 12: 429-444. Levasseur, M., Gosselin. M. and Michaud, S., 1994. A new source of dimethylsulfide (DMS) for the Arctic atmosphere: ice diatoms, Mar. Biol., 121: 381-387. Longhurst, A.R., 1991. Role of the marine biosphere in the global carbon cycle. Limnol. Oceanogr., 36: 1507- 1526. Longhurst, A.R., Bedo, A.W., Harrison, W.G., Head, E.J.H. and Sameoto, D.V., 1990. Vertical flux of respiratory carbon by oceanic die1 migrant biota. Deep-Sea Res., 37: 685-694. Manak, D.K. and Mysak, L.A., 1989. On the relationship between Arctic sea ice anomalies and fluctuations in northern Canadian air temperature and river discharge. Atmos. Ocean, 27: 68% 691. Marsden, R.F., Ingram, R.G. and Legendre, L., 1994a. Currents under land-fast ice in the Canadian Arctic Archipelago Part 2: Vertical mixing. J. Mar. Res., 52: 1037-1049. Marsden, R.F., Paquet, J.R. and Ingram, R.G., 1994b. Currents under land-fast ice in the Canadian Arctic Archipelago Part 1. Vertical velocities. J. Mar. Res., 52: 1017-1036. Marsden, R.F.. Juszko, B.A. and Ingram, R.G., 1995. Jntemal wave directional spectra using an acoustic Doppler current profiler. J. Geophys. Res., loo(C8): 16,179-16,192. Paquet, JR., 1993. Internal solitary waves with acoustic applica-
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tions to the Canadian Arctic and the Scotian Shelf. M.Sc. Thesis, Phys. Dep., Royal Roads Military College, Victoria, B.C., 88 pp. Ramanathan, V., Cicerone, R.J., Singh, H.B. and Kiehl, J.T., 1985. Trace gas trends and their potential role in climatic change. J. Geophys. Res., 90: 5547-5566. Raven, J.A., 1993. Limits on growth rates. Nature, 361: 209-210. Riebesell, U., Wolf-Gladrow. D.A. and Smetacek, V., 1993. Carbon dioxide limitation of marine phytoplankton growth rates. Nature, 36 1: 249-25 1. Shirasawa, K. and Ingram, R.G., 1995. Comparative study of oceanographic characteristics above/under first-year sea ice at low and high latitudes. Proc. NIPR Symp. Polar. Biol., 8: 20-28. Shirasawa, K., Ikeda. M., Takatsuka, T., Ishikawa, M., Aota, M., Ingram, G.. Belanger, C., Peltola, P.. Takahashi, S., Matsuyama, M., Hudier, E., Fujiyoshi, Y., Kodama, Y. and Ishikawa. N., 1993. Atmospheric and Oceanographic Data Report for Saroma-ko Lagoon of the SARES (Saroma-Resolute Studies) Project, 1992. Low Temp. Sci. Ser. A, Data Rep. 52, 167 pp. Smith, R.E.H., Demers, S., Hattori, H., Kudoh. S., Legendre, L., Michel, C., Gosselin, M., Robineau, B., Suzuki, Y., Takahashi, M., Therriault, J.C., Juniper, S.K. and Sime-Ngando, T., 1995. Biological and chemical investigations of the SaromaResolute project in ice-covered Resolute Passage, 1392. Can. Data Rep. Hydrogr. Ocean Sci. 137, 19 pp.
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