中亚降水和气温的时空演变特征

Spatial Evolution Characteristics of Precipitation and Air Temperature over Central Asia

为提升对中亚地区区域气候变化规律的认识,利用1936-2018年的CRU逐月降水和气温资料,采用一元线性回归和11年滑动平均等统计方法,将中亚划分为4个区域,分析不同区域中亚降水和气温的时空演变特征。结果表明:(1)中亚的气温和降水在春季和冬季年际变率最大,前者的大值区位于哈萨克斯坦的北部,后者的大值区位于帕米尔高原及邻近区域。(2)中亚不同区域各季节气温均呈显著增暖趋势,尤其春季和冬季的高纬度地区,降水变化呈现明显的区域差异,降水增加主要体现在春季和冬季的高纬度地区(Ⅱ区和Ⅲ区)和夏季的帕米尔高原和天山一带(Ⅰ区)。(3)过去83年,中亚各区域主要经历了3~4个气候类型,近20余年,主要体现为暖-干型和暖-湿型。各区域春季和冬季降水对气温增暖响应一致性较好,均为暖-湿型,秋季中亚中纬度地区(Ⅰ区和Ⅳ区)降水和气温一致变化,而高纬度地区(Ⅱ区和Ⅲ区)气温和降水相反变化,为暖-干型。

In order to improve the understanding of the regional climate change law over Central Asia,the Central Asia is divided into four sub-regions,and the temporal and spatial evolution characteristics of precipitation and temperature over Central Asia are analyzed by using statistical methods such as linear regression and 11-year moving average over Central Asia from 1936 to 2018,and based on the CRU monthly precipitation and temperature data.The results show that(1)the interannual variability of air temperature and precipitation in spring and winter are the largest over central Asia,and the maximum values of the former(latter)are located in the northern parts of Kazakhstan(Pamir Plateau and its adjacent areas).(2)The air temperature over whole Central Asia shows significant warming trends in different season and sub-region,especially in the high latitudes in spring and winter.There are obvious regional differences in precipitation changes,and the increase of precipitation is mainly concentrated on the high latitude regions(sub-regionsⅡandⅢ)between spring and winter and the Pamir Plateau and Tianshan Mountains(sub-regionⅠ)in summer.(3)During the past 83 years,the regional climate over Central Asia has experienced 3-4 types,and for recent two decades the climate mainly belongs to warm-dry type and warm-wet type.In spring and winter,the precipitation is well corresponded to the warming of air temperature over various region of Central Asia in different season,which all present warm-wet type.In the Autumn,precipitation and air temperature in the middle latitudes of Central Asia(sub-regionⅠandⅣ)show similar change,but they show contrary changes in the high latitudes of Central Asia(sub-regionⅡandⅢ),which present warm-dry type.