摘要
依据Global Precipitation Climatology Centre(GPCC)1916-2015年冬季0.5°×0.5°分辨率的全球陆地逐月格点降水数据及欧洲中期天气预报中心(ECMWF)1916-2015年1.0°×1.0°分辨率的ERA-20C和ERA-Interim败据集,分析了近百年中亚干旱区(中亚五国和中国新疆)冬季年降水的时空变化及其可能影响机制。结果发现,中亚干旱区作为一个整体,近百年冬季年降水整体表现出明显的增加趋势(0.11mm/年),且20世纪70年代中期发生明显突变。从区域上看,中亚干旱区冬季年降水突变前后降水中心位置不变,均位于中亚千旱区中南部(土库曼斯坦东部、塔吉克斯坦和吉尔吉斯斯坦);但突变后降水增幅中心与降水中心不一致,位于哈萨克斯坦北部。影响中亚干旱区冬季年降水突变的主要因素可能是:高纬地区高度场负异常和地中海地区高度场正异常,使得中纬西风带纬向的水汽向中亚干旱区的输送加强;东欧平原至红海地区东北-西南向高度场负异常和阿拉伯海至中国新疆地区东北-西南向高度场正异常,使得红海经向的水汽向中亚干旱区西北部的输送加强。
The spatiotemporal variation characteristics and influencing factors of wintertime annual precipitation in arid Central Asia(ACA)in the past century are analyzed using the monthly 0.5°×0.5°gridded precipitation data from Global Precipitation Climatology Centre(GPCC)and the European Center for Medium-Range Weather Forecasts(ECMWF)monthly 1.0°× 1.0°gridded reanalysis data in 1916-2015.The results showed that the wintertime annual precipitation indicated a significantly increasing trend in ACA in the past century(0.11 mm/a),which changed abrutly in ACA in the mid-1970s.Regionally,the location of precipitation center remained the same(the central-south of ACA,including eastern Turkmenistan,Kyrgyzstan and Tajikistan)before and after the abrupt change;the precipitation growth center is located in northern Kazakhstan after the abrupt change of the wintertime annual precipitation.The main influencing factors of abrupt change of the wintertime annual precipitation in ACA include:the negative height anomaly over the high latitudes together with the positive height anomaly over the Mediterranean strengthened the zonal water vapor transported from the mid-latitude westerlies to ACA,and the northeast-southwest negative height anomaly over the Eastern European Plain to the Red Sea and the northeast-southwest positive height anomaly over the Arabian Sea to the Xinjiang of China strengthened the zonal water vapor transported from the Red Sea to the northwest ACA.Besides,EA,NINO,SO and EP-AP had certain influences on the abrupt change of wintertime annual precipitation in ACA.
作者
李亚云
LI Yayun(Beijing Institute of Applied Meteorology,Beijing 100029,China;State Key Laboratory of Geo-Information Engineering,Xi'an 710054,China)
出处
《测绘科学与工程》
2021年第3期86-91,共6页
Geomatics Science and Engineering
关键词
中亚干旱区
冬季年降水
时空特征
突变
大气环流
the Arid Central Asia
wintertime annual precipitation
spatiotemporal characteristics
abrupt change
atmospheric circulation
