气候变化背景下陆地季风与非季风区极端降水特征对比

Land Monsoon and Non-monsoon Regions under Climate Change Comparison of Extreme Precipitation Characteristics

利用月平均地表气候要素数据集(CRU TS 4.02)的逐月降水和逐月日平均气温资料,采用线性趋势分析、滑动平均和相关分析等方法,研究了1901-2017年气候变化背景下全球陆地季风区与非季风区的极端降水特征。结果表明:我国所处的亚洲季风区的极端降水频率分布较为稳定,仅在变暖减缓时段出现大范围小值区;非季风区在急剧加速变暖时段极端降水频率分布呈现两极化,大范围的小值区与大值区共存,而季风区不易出现这种情况。季风与非季风区极端降水频率均值变化基本趋于一致,只在加速变暖时段有所不同。季风与非季风极端降水频率小值区格点数占比变化趋于一致,仅在两个加速变暖时段有所区别,而对于大值区,除去1921-1949年和1950-1972年,季风区大值区格点数占比均低于非季风区。季风与非季风区极端降水量的分布形式受气候变化影响相对较小,但无论处于哪个冷暖时段,季风区的极端降水量均远远高于非季风区。非季风区的极端降水频率与气温的相关性要好于季风区,叠加温度趋势变化时,中高纬度大部分地区呈正相关的关系,去趋势后,相关性减弱。

This article uses the monthly precipitation and monthly daily average temperature data from the monthly average surface climate element data set(CRU TS 4. 02),and uses linear trend analysis,moving average and correlation analysis methods to study the background of climate change from 1901 to 2017 The characteristics of extreme precipitation in the global terrestrial monsoon and non-monsoon regions. The results show that the frequency distribution of extreme precipitation in the Asian monsoon region where China is located is relatively stable,and only large-scale and small-value areas appear during the warming slowing period;the non-monsoon area shows a polarization in the frequency distribution of extreme precipitation during the Sharply accelerated warming period. The small value area and the large value area coexist in the monsoon area,which is not easy to occur. The average change of extreme precipitation frequency in monsoon and non-monsoon regions basically tends to be the same,and only differs during periods of accelerated warming. Monsoon and non-monsoon extreme precipitation frequency changes in the proportion of grid points in the small value area tend to be consistent,and only differ in the two accelerated warming periods. For the large value area,excluding the periods of1921-1949 and 1950-1972,the monsoon area is larger. The proportion of grid points in the value area is lower than that in the non-monsoon area. The distribution of extreme precipitation in monsoon and non-monsoon regions is relatively less affected by climate change,but no matter which period of cold or warm,the extreme precipitation in monsoon regions is much higher than that in non-monsoon regions. The correlation between extreme precipitation frequency and temperature in non-monsoon regions is better than that in monsoon regions. When temperature trends are superimposed,most areas of mid-to-high latitudes are positively correlated. After detrending,the correlation weakens.