Long-term Variability and Dynamic Mechanism of the Kuroshio-induced Atmospheric Convergence Zone

The strong western boundary currents bring warm tropical waters into high latitude areas, causing net meridional heat transports. The western boundary current in the Northwestern Pacific is referred to as the Kuroshio which flows along the East China Sea continental shelf slope. The high temperature Kuroshio water fluxes heat into atmosphere, producing an atmospheric convergence zone, and the convergence can extend to the entire troposphere. The atmospheric convergence has two direct impacts on the climate: one is the heat transport from ocean to the upper level atmosphere, and the other is the hydrologic forcing, which causes local rainfall and a rainfall source for other areas. The ACZ caused by the Kuroshio in the Northwestern Pacific, therefore, has a great impact on the climate of East Asia. In this study, we explore the long-term variability of the Kuroshio-induced ACZ using Satellite scatterometer winds and develop a dynamic mechanism of the Kuroshio-induced ACZ. The results elucidate effects of the warm ocean current on the regional atmospheric circulation, and roles of ocean on the regional climate in East Asia.