CS26 Organic Carbon Dynamics
Date: Thursday, June 13, 2002
Location: Carson C
 
ShinKH, University of Alaska Fairbanks, Fairbanks, AK, USA, shinkh@iarc.uaf.edu
Tanaka, N, , Hokkaido University, Sapporo, Japan, 
 
DISTRIBUTION AND SOURCE OF DISSOLVED ORGANIC MATTER (DOM) IN THE NORTHERN BERING SEA AND WESTERN ARCTIC OCEAN
image
To investigate the distribution and source of dissolved organic carbon (DOC) in the northern Bering Sea, Chukchi Sea (Barrow Canyon), Beaufort Sea and the western Arctic Ocean, seawater samples of DOC and DOM analysis were collected during Mirai Arctic Ocean Cruises (MR00-K06) in summer 2000. DOC concentrations were high (about 100 uMC) near the Yukon River estuary in the northern Bering Sea, and also extremely high (max. 300 uMC) near the Mackenzie River estuary in Beaufort Sea. However, low DOC concentrations were measured in the ice melt water and detected Atlantic water (7580 uMC and 48-60 uMC, respectively). On the other hand, we found high DOC concentrations (86-94 uMC) in some portions of cold halocline waters at Barrow canyon. Dissolved fatty acid composition suggests that the origin of DOC enriched cold halocline water parcels should be close to marine algal sources rather than terrestrial organic matter. Particularly, polyunsaturated fatty acids were only seen in DOM at the cold halocline water, showing that labile DOC is transported by the outflow of cold halocline water through Barrow Canyon, western Arctic Ocean.