The Warming and Wetting Ecological Environment Changes over the Qinghai-Tibetan Plateau and the Driving Effect of the Asian Summer Monsoon

Abstract

The impact of warming and wetting on the ecological environment of the Qinghai-Tibet Plateau (TP) underthe background of climate change has been a concern of the global scientific community. In this paper, the optimizedinterpolation variational correction approach is adopted for the analysis of monthly high-resolution satellite precipitationproducts and observations from meteorological stations during the past 20 years. As a result, the corrected precipitationproducts can not only supplement the“blank area”of precipitation observation stations on the TP, but also improve theaccuracy of the original satellite precipitation products. The precipitation over the TP shows different spatial changes inthe vegetation growing season, known as the time from May to September. The precipitation in the vegetation growingseason and leaf area index (LAI) in the following month show a similar change pattern, indicating a“one-month lag”response of LAI to precipitation on the TP. Further analysis illustrates the influence of water vapor transport driven bythe Asian summer monsoon. Water vapor derived from trans-equatorial air flows across the Indian Ocean and ArabianSea is strengthened, leading to the increase of precipitation in the central and northern TP, where the trend of warmingand wetting and the increase of vegetation tend to be more obvious. By contrast, as a result of the weakening trend ofwater vapor transport in the middle and low levels in southern TP, the precipitation decreases, and the LAI shows adowntrend, which inhibits the warming and wetting ecological environment in this area.