1979-2010年中国流域水汽含量变化

为进一步丰富对中国上空水汽含量与可降水量气候平均状态及其变化的认识,利用日本气象中心的再分析资料,计算得到中国平均水汽含量分布图和各个季节水汽含量分布图。以再分析资料为基础计算得到的分布图与以探空资料为基础得到的分布图进行比较,可验证二者的合理性和不足之处。以流域为单元,分析了1979-2010年中国大陆区流域含量变化,结果表明:中国各流域年平均可降水量的年际变化都不大,变差系数都小于0.1;年际变化最大的处于中国西北地区的流域,变差系数都大于0.06;年平均可降水量呈显著增加的流域有北疆、塔里木内流区、河西走廊及阿拉善地区、柴达木内流区和羌塘内流区,呈显著减少的流域有东南诸河和内蒙古内流区,其他流域变化不显著。

Trends in moisture content for 1979-2010 in China river basins

In order to understand the current status of atmospheric moisture content and to analyze the spatial and temporal variations in the distribution of precipitable water over China, the Japan Meteorological Agency reanalysis data set is used to map distributions of annual and seasonal moisture content for 1979-2010. The obtained maps are compared to those based on sounding data, and necessary corrections to the maps are made accordingly. The study uses China river basins as units for the trend analysis of moisture content. The result shows that there is a little interannual variation in the annual moisture content in each of the China river basins, as revealed by small values of the coefficient of variation (C_V<0.1) for each basin separately. The higher values of C_V>0.06 are found in river basins of Northwest China. Significant upward trends in annual precipitable water have been detected in river basins of Beijiang, Tarim, Hexizoulang and Alashan, Qaidam and Changtang. The opposite is true for river basins of Southeast and Inner Mongolia. No significant trend in moisture content has been found in the rest of China river basins.