近40a中国不同量级降水对年降水量变化的影响性分析

采用1968-2007年全国595个气象台站的日降水资料，将降水量分为0．1～9．9mm、10～24．9mm、25～49．9mm和≥50mm共4个不同量级降水，通过趋势系数等统计诊断方法，分析了年雨日与年降水量相关性、年雨日与日平均降水强度的变化趋势、不同量级降水的日数和强度的变化趋势以及它们分别对年降水量变化的影响。...

Impact Analysis of Precipitation in Different Classes on Annual Precipitation Change in Recent 40 Years in China

Based on daily precipitation during the period of 1968 -2007 at 595 meteorological stations in China divided to four different precipitation classes ranging from 0.1 - 9.9 mm, 10 -24.9 mm, 25 49.9 mm to over or equal to 50 mm, the similarity relationship between annual rainy days and annual precipitation, the tendencies of annual rainy days and daily average precipitation intensity, the tendencies of rainy days and precipitation intensities in different classes and their effects on the change of annual precipitation amounts were analyzed respectively by using statistical diagnostic methods such as the trend coefficients. The results are as follows. 1 ） Similarity relationship between annual rainy days and annual precipitation decreased and had a significant shift around 1980s, that＇ s to say, the annual precipitation became more related to daily average precipitation intensity since then. 2） Annual rainy days in China except Xinjiang, Eastern Tibet, Qinghai and the western of Sichuan appeared increased, most of the rest of the region decreased. Daily precipitation intensity in Middle China, Eastern China, Southern China, Northeast China and part of Western China appeared increased while other regions no obvious variations. Annual precipitation in the western of Northwestern and Southwestern China, the Yandtze-Huaihe valley, Yangtze River delta and Southeastern Coast China increased while the eastern of Northwestern and South- western China, the western of Southern China, the southern of Northeastern China and Northern China decreased. 3） The changes of annual precipitation were mainly caused by the rainy days for the areas whose annual precipitation decreased, while the changes of annual precipitation were caused by both the rainy days and precipitation intensities for the areas whose annual precipitation increased.