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

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. Plain Language Summary The study researched the influences of the Kuroshio SST front to the marine atmospheric boundary layer (MABL) in wintertime over East China Sea and Yellow Sea with the sea surface temperature (SST) forcing climate numerical experiments. The significant different MABL responses exit under three different typical prevailing wind conditions. For NE wind directions, the SLP adjustment mechanism dominates the atmospheric adjustment and the variances of scalar wind and vector wind are similar. However, for NW wind directions, both the SLP adjustment mechanism and vertical mixing mechanism play an important role. The maximum variations of the scalar wind are just over the core SST front, whereas maximum vector wind variations are over warm flank. For SE wind directions, the vertical mixing mechanism contributes more to the MABL responses. The maximum variations of the scalar wind occur over the core SST front, which is beyond the top of MABL. The further diagnosis analysis showed that the meridional transient eddies and mean flow interaction contribute to the scalar wind variations under cross-front conditions, which term is neglected in previous studies. The results might give the new insight to studies of SST front, which have important implications for East Asian climate scientists and predictions.