Impact of the Atlantic Meridional Overturning Circulation on the Upper Water Temperature of the North Atlantic and the Atlantic Sector of the Arctic Ocean

In this study, we investigate the impact of variability of the Atlantic Meridional Overturning Circulation (AMOC) on water temperature of the upper 100-m layer of the North Atlantic and Arctic Ocean. We use three datasets (ARMOR-3D, SODA3.4.2, and ORAS4) with different spatial resolutions and coverage of different time periods. The temperature variability is decomposed into its natural modes using empirical orthogonal functions (EOF). The second EOF, which accounts for 20-27% of variance of water temperature in the upper ocean, is associated with a change in the AMOC intensity. The time variability of the principal component of this mode has a high correlation with the AMOC (0.6-0.9 depending on the dataset and AMOC index used). The AMOC has the highest impact on water temperature in the Irminger and Labrador seas. The related amplitude of water temperature fluctuations reaches 1.5-2 degrees C in the central Irminger Sea, one of the key areas of deep convection. Intensification of the AMOC over most of the North Atlantic and in the Norwegian Sea leads to a decrease in water temperature over most of the Greenland Sea, in the Barents Sea, and north of Spitsbergen.