Impacts of the Kuroshio intrusion entering the Luzon Strait on the local atmosphere by satellite observations

Abstract

The Kuroshio is the western boundary current of the North Pacific Ocean. Kuroshio intrudes into the north of South China Sea (SCS) through the Luzon Strait. The intruded Kuroshio often forms an anticyclonic current loop north of the Luzon Strait. Previous studies confirmed co-variability of sea surface temperature (SST) influence on the local atmosphere. In this study, by using satellite data and numerical modeling, the impact of Kuroshio intrusion (KI) entering north Luzon Strait on the local atmosphere is investigated. First, satellite data analysis shows that KI causing increased local sea surface temperature and enhanced intensity of wind speed and rainfall off southwestern Taiwan during easterly winds (from November to April). Moreover, based on vertical velocity (w) of atmosphere derived from reanalysis data, the result shows that higher local SST (associated with KI) triggering enhanced wind speed and rainfall by enhancing lower atmosphere vertical motion and thus decreasing vertical wind shear, which leads to intensify of vertical mixing.