Does Warming of the Tibetan Plateau Intensify or Weaken the Precipitation Rate of Landfalling Tropical Cyclones in China?

Abstract

China faces the Northwest Pacific with the world's most active tropical cyclones (TCs). Whether and how the warming of the “Roof of the World”, the Tibetan Plateau (TP), influences the environmental field and precipitation of landfalling TC (LTC) remains unclear. In this study, a data-driven objective classification reveals that the key environmental field influencing the LTC precipitation in China is closely related to the TP-related high pressure. The precipitation rate of LTC in China exhibits an overall increasing trend over the past 43 years under TP warming. However, the trend of the precipitation rate depends on environmental fields. For LTCs affecting southeastern China, the South Asian High (SAH) intensifies and extends eastward, the Western Pacific Subtropical High (WPSH) shifts westward but weakens, stabilizing the atmosphere and reducing precipitation rate. For LTCs impacting southern China, the SAH and WPSH strengthen, increasing atmospheric instability and enhancing precipitation rate.