HR: 0800h
AN: OS41A-0473    [Abstracts]
TI: The Nordic Seas 2002 Survey: Water Mass Comparisons with Previous Surveys
AU: * Swift, J
EM: jswift@ucsd.edu
AF: UCSD Scripps Institution of Oceanography, 9500 Gilman Dr., La Jolla, CA 92093-0214 United States
AB: The Nordic Seas survey completed by Icebreaker Oden and R/V Knorr during April-June 2002 provides not only nearly complete lateral and vertical coverage of the Nordic Seas but also an excellent basis for comparisons with earlier surveys. The classic Greenland Sea Deep Water, which has been steadily eroded ever since the early 1980s, is essentially gone today. In the 2002 data, salinities on deep isopycnals show little variability across the Nordic Seas, except for influence of saline waters from the Arctic Ocean and dense waters from Storfjorden, with essentially no remaining signal from what was earlier a strong, fresh deep water source in the central Greenland Sea. The vertical structure of the water masses across the Nordic Seas clearly show a remarkable transition of the Greenland Sea from its appearance in nearly all pre-1990s data. Nordic Sea winter-produced intermediate waters exhibit no companion temporal decrease in presence: in 2002 there were typically slightly greater thicknesses of key intermediate layers, with about the same (high) average dissolved oxygen concentrations, as in the 1980s data, albeit in 2002 with slightly higher average salinities. It is interesting that the central Greenland Sea vertical structure has shifted from a quasi-one-layer regime to a two-layer one, even though upper salinities are relatively high in recent data. This fosters speculation regarding the possible role of warmer air temperatures, particularly in winter, in bringing about the regime transition.
DE: 4207 Arctic and Antarctic oceanography
DE: 4215 Climate and interannual variability (3309)
DE: 4223 Descriptive and regional oceanography
DE: 4283 Water masses
SC: Ocean Sciences [OS]
MN: 2004 AGU Fall Meeting