Northern high-latitude climate changes during the Holocene as simulated by circulation models.


Contact
lohmann [ at ] awi-bremerhaven.de

Abstract

A global coupled atmosphere-ocean circulation model is driven by astronomical forcing in order to simulate the Holocene climate. In the Nordic Seas region, we find a long-term climate sea surface temperature decrease associated with changes in seasonal sunlight distribution. In the North Atlantic realm, a continuous cooling in the northeastern Atlantic was accompanied by a persistent warming in the Labrador Sea from the middle to the late Holocene. This temperature pattern during the Holocene can be attributed to a continuous weakening of the Icelandic Low and altered winds in the Nordic Seas. Part of the shift in the Northern Hemisphere atmospheric circulation is characterized by a tendency towards a negative phase of the Arctic Oscillation/North Atlantic Oscillation pattern. In contrast to the middle to late Holocene, where the insolation provides a crucial forcing for northern high latitudes, the strongest forcing for the Nordic Seas region in the early Holocene was probably caused by melting ice masses and a shallower Bering Strait. The effects of freshwater discharge and Bering Strait inflow are studied in a regional model of the Arctic and North Atlantic Ocean. It is suggested that a gradual increase in the influx of Pacific water through Bering Strait during the early Holocene slowly affected the polar climate by melting ice and causing circulation changes in the Nordic Seas.



Item Type
Article
Authors
Divisions
Programs
Publication Status
Published
Eprint ID
11410
DOI 10.1029/158GM18

Cite as
Lohmann, G. , Lorenz, S. and Prange, M. (2005): Northern high-latitude climate changes during the Holocene as simulated by circulation models. , The Nordic seas : an integrated perspective ; oceanography, climatology, biogeochemistry, and modeling / Helge Drange ... editors. Washington, DC : American Geophysical Union, 273-288. (Geophysical Monograph ; 158) . doi: 10.1029/158GM18


Share
Add to AnyAdd to TwitterAdd to FacebookAdd to LinkedinAdd to PinterestAdd to Email


Citation

Research Platforms
N/A

Campaigns
N/A


Actions
Edit Item Edit Item