HR: 15:00h
AN: OS33C-05 INVITED     [Abstracts]
TI: Large-Scale Variability in the Nordic Seas: Natural Variability or Climate Change?
AU: * Furevik, T
EM: tore@gfi.uib.no
AF: Geophysical Institute, University of Bergen, Allegt 70, Bergen, 5007 Norway
AU: * Furevik, T
EM: tore@gfi.uib.no
AF: Bjerknes Centre for Climate Research, Allegt 55, Bergen, 5007 Norway
AU: Osterhus, S
EM: svein@gfi.uib.no
AF: Geophysical Institute, University of Bergen, Allegt 70, Bergen, 5007 Norway
AU: Osterhus, S
EM: svein@gfi.uib.no
AF: Bjerknes Centre for Climate Research, Allegt 55, Bergen, 5007 Norway
AB: From the 1960s to the 1990s the North-Atlantic sector experienced a large-scale change in the atmospheric circulation, going from extraordinary weak westerlies in the '60s to the strongest westerlies ever observed in the '90s. Accompanying this low frequency shift in the atmospheric forcing, astonishingly large changes have been taken place in the Nordic Seas ocean climate. We here review some of the recent findings, including the warming and narrowing of the inflowing Atlantic Water, the freshening of the intermediate water, the weakening of the convection in the Greenland Sea, the warming of the deep waters, and the possible reduction of the overflow waters feeding the Atlantic meridional overturning circulation. These changes, many unprecedented in historical records, are observed in a period with increasing levels of atmospheric CO2. According to most climate models, the result of the greenhouse gas forcing will be much higher air temperatures and increased precipitation over the northern high latitudes, a thinner and smaller ice cover, a more shallow oceanic convection, and finally a reduced overflow and a weakening of the overturning circulation. With all the evidence at hand, it is tempting to ask; are we witnessing the first of many inevitable man-made changes in the Nordic Seas climate?
DE: 3339 Ocean/atmosphere interactions (0312, 4504)
DE: 4207 Arctic and Antarctic oceanography
DE: 4215 Climate and interannual variability (3309)
DE: 4283 Water masses
DE: 4536 Hydrography
SC: Ocean Sciences [OS]
MN: 2004 AGU Fall Meeting