Arctic shelves

Superimpose the attributes of the Arctic environment upon the cycles of these biological precursors, and what arises is a system of biological production, transformation and losses unique in the global ocean system. Continental shelves are a key feature that influence greatly the production and cycling of organic matter in the Arctic Ocean. Water masses exiting different Arctic shelves... 

Table 22.2 Estimated Percent Labile/Marine Content for Acyclic Hydrocarbons in Arctic Shelf Sediments. ...

The Western Arctic Shelf-Basin Interactions (SBI) project, sponsored by the ARCSS Program and the U.S. Office of Naval Research, is investigating the Arctic marine ecosystem to improve our capacity to predict environmental change. The SBI Phase II Field Implementation Plan (2002-2006) (Grebmeier et al., 2001) focuses on three research topics in the core study area ... 

Canadian Arctic Shelf Ecosystem Study (CASES), which is an international effort under Canadian leadership to understand the biogeochemical and ecological consequences of sea ice variability and change on the Mackenzie Shelf in the Beaufort Sea (Arctic Ocean). 

Grebmeier J.M. Whitledge T.E. Aagaard K. Bergmann M. Carmack E.C. Codispoti L.A. Darby D. Dunton K.H. Melnikov I.A. Moore S. Takizawa T. Walsh J.J. Wassman P. and Wheeler P. (eds.) (2001). Arctic System Science Ocean-Atmosphere-Ice Interactions Western Arctic Shelf-Basin Interactions (SBI). Phase II Field Implementation Plan, SBI Project Office, The University of Tennessee, Knoxville, Tennessee, 30 pp. 

Cloud And Radiation Testbed Carnegie-Ames-Stanford Approach Canadian Arctic Shelf Ecosystem Study Cloud/Column... 

Devol, A. H., Codispoti, L. A., and Christensen, J. C. (1997). Summer and winter denitrification rates in western Arctic shelf sediments. Cont. Shelf Res. 9, 1029-1050. 

These statistics underscore the importance of the continental shelf areas to the structure and function of the Arctic Ocean system. Arctic shelf seas are the primary sites for processing and modifying the characteristics of waters received from the Pacific and Atlantic Oceans and the numerous large rivers that drain the circumpolar continents. All of these inflows are substantially altered on the shelves by mixing and by interactions with the ice cover, atmosphere, seabed and biota. The water mass properties that generate and maintain the halocline in the Arctic Ocean (see Section 5.2.1) are derived from the modification of inflowing Atlantic and Pacific waters while transiting continental shelves. 

Terrestrial and marine biomarkers have aided in understanding how Arctic shelf systems process, metabolize and sequester carbon (Opsahl etal., 1999). Biomarkers have been used to trace the dispersal of DOC and POC on the Canadian Beaufort shelf, leading to a better understanding of the importance of terrestrial sources to the carbon budget of major riverine-influenced systems (Yunker etal., 1995 Macdonald etal., 1998). 

Grebmeier, J.M. etal. (eds) (1998) Arctic System Science Ocean—Atmosphere—Ice Interactions Western Arctic Shelf-Basin Interactions Science Plan, ARCSS/OAII Report 7, Old Dominion... 

Carey, A. G. 1991. Ecology of North American Arctic shelf benthos a review. Cont. Shelf Res. 11 865-83. 

To recover oil from the continental shelf of arctic Canada and Alaska, drilling and production platforms must be built some miles offshore, in roughly 40 m of water. This is not a great depth, and would present no new problems were it not that the sea freezes in winter to a depth of around 2 m. Wind blowing across the surface of the ice sheet causes it to move at speeds up to 1 m s pressing it against the structure. Ice is... 

Baskaran and Santschi (1993) examined " Th from six shallow Texas estuaries. They found dissolved residence times ranged from 0.08 to 4.9 days and the total residence time ranged from 0.9 and 7.8 days. They found the Th dissolved and total water column residence times were much shorter in the summer. This was attributed to the more energetic particle resuspension rates during the summer sampling. They also observed an inverse relation between distribution coefficients and particle concentrations, implying that kinetic factors control Th distribution. Baskaran et al. (1993) and Baskaran and Santschi (2002) showed that the residence time of colloidal and particulate " Th residence time in the coastal waters are considerably lower (1.4 days) than those in the surface waters in the shelf and open ocean (9.1 days) of the Western Arctic Ocean (Baskaran et al. 2003). Based on the mass concentrations of colloidal and particulate matter, it was concluded that only a small portion of the colloidal " Th actively participates in Arctic Th cycling (Baskaran et al. 2003). 

Sweeney MD, Naidu AS. 1989. Heavy metal in sediments of the inner shelf of the Beaufort Sea, northern arctic Alaska. Marine Pollution Bulletin 20 140-143. 

Efimova, V.M. (1982). Electromyogram as an indicator of the adaptation to prolonged swimming (In Russian). In Biology of Shelf Waters of the World Ocean (A.J. Kafanov, ed.), pp. 166-167. (Proceedings of the II Conference on Marine Biology, Far East Scientific Centre of Arctic Science of USSR.)... 

Compared with the open water of the Arctic Ocean, the shelf seas of the Russian Arctic are more heavily contaminated. 

Arctic Ocean Shelf Studies, which are aimed at understanding how shelf processes partition saltwater and freshwater components and at defining the dynamics and thermodynamics of shelf waters as well as other processes ... 

Another important project is the Russian-American Initiative on Shelf-Land Environments in the Arctic (RAISE) with the principal goal of facilitating ship-based research in the Russian Arctic (Cooper and Romanovsky, 2001). Earlier relevant land-based research projects under the RAISE umbrella included studies of... 

New scientific topics in the near-shore waters of the Russian continental shelf will include a broad range of studies from the biogeochemical fate of organic material contributed to the Arctic Ocean by shoreline erosion and river run-off" to the social and biological impacts of changes in sea ice distribution. 

Baskaran, M., and Naidu, S. (1995) 210Pb-derived chronology, and the fluxes of 210Pb and 137Cs isotopes into continental shelf sediments, East Chukchi Sea, Alaskan Arctic. Geochim. Cosmochim. Acta 59, 4435-4448. 

Pitznar, H. P. (1999). D-Amino acids as tracers for biogeochemical processes in the river-shelf ocean-system of the Arctic. Alfred-Wegmer Institute Reports on Polar Research 334, 116. 

In April 1969 the Canadian Petroleum Association estimated the ultimate potential raw recoverable natural gas reserves of Canada to be 720.9 Tcf (at 14.73 psia and 60°F). If the total raw recoverable gas discovered through 1970 is subtracted from this value, a remaining undiscovered potential of 634.8 Tcf of raw gas is derived. Much of this undiscovered potential is attributed to Canada s frontier areas comprised of Northern Canada, Arctic Islands, Mackenzie Delta, Hudson Bay, and the continental shelf areas off the Atlantic, Paciflc, and Arctic Coasts. 

Figure 3 Predicted plate spacings without (dashed curve) and including the convection model with two upper limits in the Nusselt number (solid and dotted lines). Crosses refer to observations compiled from sea ice field studies and circles to laboratory data at comparable NaCl concentrations from- 25 to 31 %o. The low velocity points refer to thick arctic sea ice (square) and the bottom of an Antarctic ice shelf (triangles).

MMGEP includes the blocks describing the function of the world ocean pelagic, arctic and shelf ecosystems. The world ocean is divided in four parts Arctic, Pacific, Atlantic and Indian Oceans. 

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