Abstract:Based on the CMAP and GPCP precipitation data and the ERAInterim reanalysis data during 1979-2016, this study examines the relationship between midupper tropospheric temperature in the Tibetan Plateau (TP) and precipitation in the subtropical western North Pacific (WNP) during boreal summer and analyzes the associated physical processes. The results show a significant positive correlation between the TP midupper tropospheric temperature and the subtropical WNP precipitation on the interannual scale. When temperature in the midupper troposphere is high over the TP, the South Asian high is significantly enhanced and extends eastward to Japan. Meanwhile, there is an anomalous upward flow in the northern TP, and it gradually shifts northward with height, expanding eastward to Japan along anomalous westerly winds to the north of the enhanced South Asian high and moving downward in the area south of Japan. Corresponding to the anomalous downward motion to the south of Japan, there is a lowertroposphere anomalous anticyclonic circulation in the southern Japan, with the northerly wind anomalies to the east of the anomalous anticyclonic circulation, which is closely related to the anomalous cyclonicanticyclonic circulation coupling structure in the lowertropospheric WNP. This coupling structure in the subtropical WNP provids favorable dynamic and water vapor conditions for the occurrence of the subtropical WNP precipitation. This process gives a physical explanation for the relationship between the TP midupper tropospheric temperature and the subtropical WNP precipitation.