Satellite evidence of wintertime atmospheric boundary layer responses to multiple SST fronts in the Japan Sea

We present satellite evidence of wintertime atmospheric boundary layer responses to multiple sea surface temperature (SST) fronts in the Japan Sea under cold-air outbreak during 22-28 December 2005. It is found that the lower atmosphere adheres to the stepwise SST variations, focusing on a wind trajectory from the Eurasian continent to the northern Japan, which goes through the meandering Polar Front and the Tsushima Warm Current. Wind speed anomaly and wind divergence are linearly related to the SST anomaly and downwind SST gradient, respectively. Vertically uniform layers of potential temperature are accomplished when reaching the Polar Front and Tsushima Warm Current. Variations of water vapor mixing ratio and the resulting surface turbulent heat fluxes show also stepwise increases. Little wind vertical shear on the Japanese coast suggests that well-mixed boundary layer is eventually formed.