中等排放情景下中国未来不同强度降雨变化及其对总降雨贡献的预估(2006—2100年)

Pre-estimation on variations of rainfalls with different intensities and their contributions to total rainfall under emission scenarios in China from 2006 to 2100

为探究中国整体和不同区域的不同强度降雨雨量及其对总降雨雨量贡献率的变化趋势,采用RCP6.0中等排放情景下2006—2100年WRF 30 km×30 km日值降水数据,根据中国气象局颁布的降水强度等级划分标准进行研究。结果表明:(1)在降雨雨量上,中等排放情景下2006—2100年中国小雨减少,强降雨增加。在降雨雨量贡献率上,小雨和中雨对总降雨的贡献率呈减少趋势,其他五种强降雨对总降雨的贡献率在增加,说明强降雨增加,降雨朝着极端化方向发展。暴雨对总暴雨的贡献率呈增加趋势,而大暴雨和特大暴雨对总暴雨的贡献率呈减少趋势,总暴雨对总降雨贡献率的增加是由于暴雨的增加起了关键作用。(2)在不同分区上,北方、东北和西藏地区不同强度降雨均呈增加趋势;东南和西南地区除小雨外均呈增加趋势;西北东部地区仅小雨、大暴雨和特大暴雨呈增加趋势;西北西部地区仅小雨、中雨和总降雨呈增加趋势。在降雨雨量贡献率上,北方和西藏地区除小雨外均呈增加趋势;东北、东南和西南地区除小雨和中雨外均呈增加趋势;西北东部地区仅小雨呈增加趋势;西北西部地区仅小雨和中雨呈增加趋势。(3)在不同强度暴雨对总暴雨贡献率上,七大分区中的特大暴雨对总暴雨的贡献率除西北西部变化趋势不显著外,其他分区均呈不同程度的增加趋势。所得成果为类似研究提供参考。

In order to explore the rainfalls with different intensities in various regions and all over China as well as the variation trends of their contributions to the total rainfall,a study is made with the WRF 30 km × 30 km daily precipitation data from 2006 to 2100 under RCP6. 0 emission scenarios in accordance with the classification standard of precipitation intensity issued by China Meteorological Administration. The result shows that（1） In the aspect of rainfall,light rains under RCP6. 0 emission scenarios from 2006 to 2100 in China are decreased along with the increases of heavy rains. For the contribution rate,the contribution rates of light rain and moderate rain to the total rainfall present the trends of decrease,while the contributions of the other five kinds of heavy rain to the total rainfall are increased,which indicates that heavy rains are increased along with rainfall being developed towards to an extreme direction. The contribution rate of rainstorm to the total storm rainfall presents a trend of increase,while the contributions of heavy rainstorm and super rainstorm to the total storm rainfall show the trends of decrease,thus the increase of rainstorm plays a key role on the increase of the contribution rate of the total storm rainfall to the total rainfall.（2） In the aspect of different regions,all the rainfalls with different intensities in the North China,Northeast China and Tibet region present the trends of increase; all the other kinds of rains in regions of the Southeast China and Southwest China present the trends of increase except light rain; only light rain,moderate rain and the total rainfall in the region of the west of the Northwest China present the trends of increase; only light rain in the region of the east of the Northwest China presents the trend of increase and only light rain and moderate rain in the region of the west of the Northwest China present the trends of increase.（3） In the aspect of the contributions of the rainstorms with different intensities to the total storm rainfall,except that the variation trend in the west of the Northwest China is not so significant,the contributions of super rainstorms within all the seven main regions present the trends of increase with various degrees. The result obtained herein can provide a reference for the similar studies.