Study on the Change of Precipitation Distribution in the southern Tibetan Plateau and southwestern China

Abstract

Global climate change has an undeniable impact on the world. In this study, we used WRF model to evaluate the spatiotemporal distribution of meteorological variables of rainfall, temperature and wind from 1979 to 2019. We found that the precipitation in the southern Tibetan Plateau and the west side of the Yunnan- Guizhou Plateau in May has a relatively significant increasing trend. This trend is highly correlated with the lowest temperature rise on the Tibetan Plateau and the Yunnan-Guizhou Plateau. In this model, two nested domains are conducted at spatial resolutions of 75 and 25 km using ERA-interim reanalysis to provide initialand lateral boundary conditions. The cumulus, microphysics, and planetary boundary layer (PBL) parameterization schemes are set by referring former studies showing good simulation results. On the other hand, comparison with the CRU V4.0.2 dataset and the measured data indicated similar spatial and temporal characters of meteorological variables. Therefore, we proposed that the more significant temperature rise in the Tibetan Plateau and the Yunnan-Guizhou Plateau in May might enhance the water vapor transport from Indian Ocean in the period of Indian pre-monsoon. With high simulating resolution of WRF model, weconfirmed the positive correlation between the water flux transport and temperature. This finding may help us examine the impact of the plateau’s more significant temperature rise on the surrounding precipitation.