3-D Thermohaline Structure of Mesoscale Eddies in the Mid-latitude Frontal Zone Revealed by Satellite and In Situ Observations
[13-Dec-2018] Hu, R., Lin, X., and Yu, L.
Presented at the 2018 AGU Fall Meeting
Measurements from the Soil Moisture Active Passive (SMAP) and Optimum Interpolation Sea Surface Temperature (OISST) acquired during 2016 to 2017 in the Kuroshio-Oyashio Extension Region (KOER) and Gulf Stream (GS) are used to reveal the sea surface salinity (SSS) and temperature (SST) structure of the mesoscale eddies with an unprecedented space and time resolution. Combined with in situ
Argo profile measurements, the vertical thermohaline structures of the eddies in these two regions are also shown: 1) Salinity anomaly is a better indicator of the existence and characteristic of eddies, especially in summer; 2) The vertical salinity structure in the KOER reveals salinity minimum at the depth of 400-600 m, roughly equal to 26.9-27 σθ, which defined as North Pacific Immediate Water (NPIW); 3) The difference between winter and summer is largest in the Oyashio; 4) The salinity and temperature anomalies of eddies is deepest in the GS, reaching around 1000m and even deeper in winter. Meanwhile, the consistency of Argo and satellite products is confirmed. Through the time evolution of sea surface height (SSH) and SSS, SST, the validity of SMAP and OISST in capturing eddy feature is further proved and the mechanism of eddy evolution is preliminarily detected.