[A-CG36] Extratropical oceans and atmosphere

[ACG36-08] Emergence of Great Salinity Oscillation over the North Atlantic in a changing climate

★Invited Papers

*Tomoki Iwakiri^1,2, Jong-Seong Kug¹, Yechul Shin¹, Ji-Hoon Oh³, Sunhee Wang¹ (1.Seoul National University, 2.Ochanomizu University, 3.Scripps Institution of Oceanography)

Keywords:Great Salinity Anomaly, Global warming

The subpolar North Atlantic is a crucial region in the climate system, as it forms dense water that drives the Atlantic Meridional Overturning Circulation (AMOC). Multiple lines of evidence have raised concerns that the AMOC weaken under global warming, which shapes unique climate change pattern such as warming whole over the North Atlantic. However, the full extent of these impacts remains uncertain. This study shows, using state-of-the-art climate models, that upper oceanic salinity variability so-called Great Salinity Anomaly over the North Atlantic exhibits an increased amplitude with a decadal time scale in a changing climate. Enhanced salinity anomaly comes from the collapse of the North Atlantic currents associated with the weakening of the AMOC. Furthermore, the associated sea surface height variability may enhance climate risks in the coastal regions of the North Atlantic.