我国逐月格点降水时空分布特征及变化趋势

Temporal and Spatial Distribution Characteristics and Change Trend of Monthly Grid Precipitation in China

基于一套空间分辨率为0.5°、时间尺度为1982~2015年的逐月格点降水资料CN05.1,利用离势系数评估法分析覆盖我国的3 781个格点月降水总量的时空分布特征,并利用三种改进的Mann-Kendall检验法(M-MK、PW-MK、TFPW-MK)对我国全境及华北、东北、华东、中南、西南、西北六大区域进行趋势变化检验。结果表明,我国降水时空分布、年际分配较不均匀;逐月格点降水量在该时期内除少数地区在个别月份呈显著上升或下降趋势外,大部分地区的降水并未呈显著且一致的变化趋势,尤其是华北、中南、华东等人口稠密地区的大部分呈较稳定态势。

With a set of monthly grid precipitation data CN05.1 with spatial resolution of 0.5 degrees and time scale from 1982 to 2015,the spatial and temporal distribution characteristics of monthly precipitation in 3781 grid points covering China were analyzed by using the method coefficient of variation evaluation method.Three improved Mann-Kendall test methods(M-MK,PW-MK,TFPW-MK)were used to test the trend changes in the whole of China and the six regions of North China,Northeast China,East China,Central South,Southwest China and Northwest China.The results show that the temporal and spatial distribution and inter-annual distribution of precipitation in China are uneven;During this period,the monthly grid precipitation showed a significant upward or downward trend in a few areas,but the precipitation in most areas did not show a significant and consistent change trend,especially in most densely populated areas such as North China,Central South and East China,showing a relatively stable trend.