Structure Of Qinghai-Tibetan Plateau Heating And Its Impacts On Precipitaion In China

The paper used NCEP I and ECMWF (ERA) reanalysis data, calculated atmospheric apparent heat source by inverse algorithm, and established data set of daily heat source for many years and verified its reasonableness. The paper especially verified and made objective judgment of vertical profile of heating rate over the plateau according to observed data of plateau tests. On these bases, we investigate the horizontal and vertical structure of Qinghai-Tibetan Plateau heating, and reveal its impacts on weather and climate in China. The major work and conclusions are as follows:1) At the maximum heat source layer, the heating rate center with the most intensity and widest extension in East Asia lies in Qinghai-Tibetan Plateau. While the total integration of the biggest heat center focusing on latent heat lies in the region from northern area in the Bay of Bengal to south plateau.2) As far as the heating vertical profiles over plateau are concerned, the results of ERA and NCEP appear reasonable. In contrast, the former is more closed to the observational facts. The monthly mean maximum heating rate height occurs dominantly between 500-600 hPa, but the daily heating profile shows that there is not merely the lower layer heating, and the upper layer heating as well.3) The strongest signals about the variability of the heat source/sink and the seasonal march heat source height are the abrupt climate change around 1990. The strongest centers of interannual variability of over Qinghai-Tibetan Plateau appear on the south central and southeast plateau.4) Numerical test indicate that, when the thermal difference between the East Asia and the western Pacific in spring is minished, the intensity of precipitation over the region to south of 30°N will decrease during the period from March to April.