Award: OCE-2038495

The NSFGEO-NERC project entitled "Collaborative Research: Subpolar North Atlantic Processes - Dynamics and pRedictability of vAriability in Gyre and OverturNing (SNAP-DRAGON)" was an international collaborative effort aimed at developing advanced understanding of subpolar North Atlantic processes that contribute to the Atlantic Meridional Overturning Circulation (AMOC). AMOC is a set of interconnected currents within the Atlantic Ocean that transport heat into high latitudes, thereby contributing to the mild climate of Western Europe. Recent observations of AMOC near the southern tip of Greenland have generated questions about the ability of ocean models to accurately represent key processes that give rise to AMOC and govern how it evolves. In SNAP-DRAGON, a variety of high-resolution models were used to examine how variations in the atmosphere at high latitudes lead to changes in AMOC. The use of high-resolution models is expensive, but they tend to be more realistic than low-resolution models. Experiments were run to test the impact of atmospheric cooling of the ocean over different regions, including the Labrador Sea and the Irminger Sea. It was found that the density of subpolar ocean water is a better indicator of how AMOC will change than the strength of subpolar ocean circulation. Furthermore, the AMOC is not driven from one particular region of the subpolar North Atlantic, but rather through the cumulative effects of cooling over the entire subpolar gyre. Cooling over the Labrador Sea is particularly effective at changing AMOC strength. These results help to inform where ocean measurements are needed to best anticipate future AMOC change.

Last Modified: 10/10/2024
Modified by: Stephen G Yeager