The sensitivity of the present day Atlantic meriodinal overturning circulation to freshwater forcing

Mounting evidence indicates that the Atlantic Meridional Overturning Circulation (AMOC) was strongly reduced during cold climate episodes in the past, possible due to freshwater influx from glacial melting. It is also expected that the freshwater input to high northern latitudes will increase as hum...

Full description

Bibliographic Details
Published in:Geophysical Research Letters
Main Authors: Otterå, Odd Helge, Drange, Helge, Bentsen, Mats, Kvamstø, Nils Gunnar, Jiang, Dabang
Format: Article in Journal/Newspaper
Language:English
Published: American Geophysical Union 2003
Subjects:
Online Access:https://hdl.handle.net/1956/804
https://doi.org/10.1029/2003gl017578
Description
Summary:Mounting evidence indicates that the Atlantic Meridional Overturning Circulation (AMOC) was strongly reduced during cold climate episodes in the past, possible due to freshwater influx from glacial melting. It is also expected that the freshwater input to high northern latitudes will increase as human-induced global warming continues, with potential impacts on the AMOC. Here we present results from a 150 years sensitivity experiment with the Bergen Climate Model (BCM) for the present-day climate, but with enhanced runoff from the Arctic region throughout the integration. The AMOC drops by 30% over the first 50 years, followed by a gradual recovery. The simulated response indicates that the present-day AMOC might be robust to the isolated effect of enhanced, high-latitude freshwater forcing on a centennial time scale, and that the western tropical North Atlantic may provide key information about the long-term variability, and by that monitoring, of the AMOC.