Title Calcium carbonate saturation in the surface water of the Arctic Ocean; undersaturation in freshwater influenced shelves
Author Chierici, M.; Fransson, A.
Author Affil Chierici, M., University of Gothenburg, Department of Chemistry, Marine Chemistry, Gothenburg, Sweden
Source Biogeosciences, 6(11), p.2421-2432, . Publisher: Copernicus GmbH on behalf of the European Union, Katlenburg-Lindau, International. ISSN: 1726- 4170
Publication Date 2009
Notes In English. Part of special issue no. 44, The ocean in the high-CO2 world II, edited by Gattuso, J.-P., et al., http://www.biogeosciences.net/special_issue44.h tml; published in Biogeosciences Discussions: 13 May 2009, http://www.biogeosciences- discuss.net/6/4963/2009/bgd-6-4963-2009.html; accessed in Feb., 2011; abstract: doi:10.5194/bg-6-2421-2009. 56 refs. GeoRef Acc. No: 308338
Index Terms animals; chlorophylls; global change; global warming; meltwater; Northwest passage; runoff; salinity; surface waters; upwelling; Canada--Arctic Archipelago; Bering Strait; Greenland--Cape Farewell; Arctic Ocean-- Chukchi Sea; Atlantic Ocean--Labrador Sea; Mackenzie River; Canada--Northwest Territories; Russia--Wrangel Island; alkalinity; Anadyr Current; aragonite; Arctic Archipelago; Arctic Ocean; Arctic region; Asia; Atlantic Ocean; benthic taxa; biota; calcite; calcium carbonate; Canada; Cape Farewell Greenland; carbon; carbon dioxide; carbonates; chlorophyll; Chukchi Sea; climate effects; Commonwealth of Independent States; fresh water; Greenland; Labrador Sea; MacKenzie Shelf; North Atlantic; North Atlantic Oscillation; Northwest Passage; Northwest Territories; organic compounds; pH; pigments; porphyrins; Russian Federation; saturation; sea water; sea-surface temperature; surface water; Western Canada; Wrangel Island
Abstract In the summer of 2005, we sampled surface water and measured pH and total alkalinity (AT) underway aboard IB Oden along the Northwest Passage from Cape Farewell (South Greenland) to the Chukchi Sea. We investigated the variability of carbonate system parameters, focusing particularly on carbonate concentration [CO32-] and calcium carbonate saturation states, as related to freshwater addition, biological processes and physical upwelling. Measurements on AT, pH at 15°C, salinity (S) and sea surface temperature (SST), were used to calculate total dissolved inorganic carbon (CT), [CO32- ] and the saturation of aragonite (Omega Ar) and calcite (Omega Ca) in the surface water. The same parameters were measured in the water column of the Bering Strait. Some surface waters in the Canadian Arctic Archipelago (CAA) and on the Mackenzie shelf (MS) were found to be undersaturated with respect to aragonite (Omega Ar‹1). In these areas, surface water was low in AT and CT (‹1500 µmol kg-1) relative to seawater and showed low [CO32-]. The low saturation states were probably due to the likely the effect of dilution due to freshwater addition by sea ice melt (CAA) and river runoff (MS). High AT and CT and low pH, corresponded with the lowest [CO32-], Omega Ar and Omega Ca, observed near Cape Bathurst and along the South Chukchi Peninsula. This was linked to the physical upwelling of subsurface water with elevated CO2. The highest surface Omega Ar and Omega Ca of 3.0 and 4.5, respectively, were found on the Chukchi Sea shelf and in the cold water north of Wrangel Island, which is heavily influenced by high CO2 drawdown and lower CT from intense biological production. In the western Bering Strait, the cold and saline Anadyr Current carries water that is enriched in AT and CT from enhanced organic matter remineralization, resulting in the lowest Omega Ar (~1.2) of the area.
URL http://www.biogeosciences.net/6/2421/2009/bg-6-2421-2009.pdf
Publication Type journal article
Record ID 65004964