Modeled MABL Responses to the Winter Kuroshio SST Front in the East China Sea and Yellow Sea

Abstract

Based on the Weather Research Forecasting (WRF) model, we designed a long-term sea surface temperature (SST)-forcing simulation to simulate the influences of SST front on the marine atmospheric boundary layer (MABL) over the East China Sea and the Yellow Sea during wintertime. The results revealed that SST front have significant relationship with MABL adjustment. The atmospheric modulations and the comparisons of the vector wind and the scalar wind indicate that the MABL responses to the SST front are quite different under different wind directions. When the prevailing wind blows parallel to the SST front (NE wind directions), the sea level pressure adjustment mechanism dominates the atmospheric adjustment. The variances of scalar wind and vector wind are similar. However, when prevailing wind crossing SST front from cold to warm (NW wind directions), both the sea level pressure adjustment mechanism and vertical mixing mechanism play an important role. The maximum variations of the scalar wind are just over the core of SST front, whereas maximum vector wind variations are over warm flank. When wind blowing from warm to cold (SE wind directions), the vertical mixing mechanism contributes more to the MABL responses. The maximum variations of the scalar wind are beyond the top of MABL, which occur over the core SST front. The further diagnosis analysis showed that the meridional transient eddies and mean flow interaction contribute to the scalar wind variations under cross-front conditions.