【來訪單位 Institution】：Research Scientist, Duke University，USA   

李非栗博士 Dr. Feili Li

Research Scientist, Duke University, USA
Ph.D. Physical Oceanography; University of Delaware, USA
B.S. Geodesy; Southwest Jiaotong University, China

Research Interests: 

Ocean circulation and climate; observation and analysis of large-scale ocean circulations; inter-gyre exchange processes; structure and dynamics of the meridional overturning circulation; sea level change; ocean observing system configuration; physical-biogeochemical coupling

Abstract: 

The Atlantic Ocean’s meridional overturning circulation (MOC), characterized by a northward flow of warm, salty water in the upper layers of the ocean balanced by a southward return flow of cold, fresh water in deeper layers, is a key mechanism for heat, freshwater, and carbon redistribution in the climate system. Paleoclimatic and modeling studies have suggested that the MOC variability is in response to changes in deep water formation in the Labrador Sea. However, recent key findings obtained from the new international OSNAP program (Overturning in the Subpolar North Atlantic Program) have called this view into question. The transatlantic observations, for the first time, reveal that the MOC and its variability in the subpolar region is largely dominated by ocean currents east of Greenland, instead of the Labrador Sea. Leading ocean-sea ice models with a strong response of the MOC in the Labrador Sea to deep water mass changes in that basin may be biased by the overproduction of deep waters in the models compared to observations. In addition to this, a close examination reveals the limitations of using indirect measurements for approximating both the strength of deep-water formation and of the MOC in the Labrador Sea, highlighting the desirability of robust estimates derived from direct monitoring, i.e., from the Argo and OSNAP measurements in the region.