春季热带海温与北疆夏季极端降水的关系研究  

Study on the relationship between tropical sea surface temperature in spring and extreme summer precipitation in northern Xinjiang

作　　者：周雅蔓 刘晶[3,4] 赵勇 马超[1] 李娜 ZHOU Yaman;LIU Jing;ZHAO Yong;MA Chao;LI Na(Xinjiang Meteorological Observatory,Urumqi 830002,China;College of Atmospheric Sciences,Chengdu University of Information Technology,Chengdu 610225,China;Institute of Desert Meteorology,China Meteorological Administration,Urumqi 830002,China;Center for central Asia Atmosphere Science Research,Urumqi 830002,China)

机构地区：[1]新疆维吾尔自治区气象台,新疆乌鲁木齐830002 [2]成都信息工程大学大气科学学院,四川成都610225 [3]中国气象局乌鲁木齐沙漠气象研究所,新疆乌鲁木齐830002 [4]中亚大气科学研究中心,新疆乌鲁木齐830002

出　　处：《冰川冻土》2021年第4期1166-1178,共13页Journal of Glaciology and Geocryology

基　　金：国家重点研发计划专项(2018YFC1507103);四川省科技计划项目(2020JDJQ0050);国家自然科学基金(41875102);中国气象局创新发展专项(CXFZ2021Z034-21-104)资助。

摘　　要：基于1961—2017年北疆47站夏季逐日降水资料、NOAA海温资料和NCEP/NCAR再分析资料,利用90%分位确定北疆夏季单站降水阈值,得出极端降水量,讨论了春季热带海温与北疆夏季极端降水的关系。结果表明:北疆夏季极端降水和春季热带印度洋(20°S~15°N,50°~110°E)及赤道东太平洋(15°S~15°N,90°~180°W)海温呈正相关,两个关键区春季热带海温异常偏暖时,北疆夏季极端降水偏多,仅春季热带印度洋关键区海温异常偏暖时,北疆西北地区夏季极端降水偏多。当春季热带印度洋和赤道东太平洋关键区海温同时异常偏暖时,200 hPa西风急流轴明显偏南,500 hPa西西伯利亚和中亚地区低值系统活跃,南方路径输送的水汽增加,有利于北疆夏季极端降水的发生;仅春季热带印度洋关键区海温异常偏暖时,200 hPa西风急流强度增强,500 hPa西西伯利亚地区低值系统活跃,配合偏东路径的水汽输送,北疆西北地区夏季极端降水偏多。Based on the daily precipitation data of 47 stations in northern Xinjiang,NOAA SST data and NCEP/NCAR reanalysis data from 1961 to 2017,the precipitation threshold of single station in northern Xinjiang in summer was determined by using 90%position,and the extreme precipitation was obtained.The relationship be⁃tween tropical sea surface temperature in spring and extreme summer precipitation in northern Xinjiang was dis⁃cussed.The results show that:the extreme summer precipitation in northern Xinjiang was positively correlated with the sea surface temperature in the Indian Ocean(20°S~15°N,50°~110°E)and the eastern equatorial Pa⁃cific(15°S~15°N,90°~180°W)in spring.When the sea surface temperature in the two key regions were ab⁃normally warmer in spring,the extreme summer precipitation in northern Xinjiang was increased.Only when the sea surface temperature in the key region of the Indian Ocean was abnormally warmer in spring,the extreme summer precipitation was increased in the northwest of northern Xinjiang.When the sea surface temperature in the two key regions of the Indian Ocean and the eastern equatorial Pacific increased abnormally in spring,the ax⁃is of westerly jet was obviously southward at 200 hPa,the low-value systems were active in western Siberia and Central Asia at 500 hPa,and the increase of moisture transported by the southern route was conducive to the oc⁃currence of extreme summer precipitation in northern Xinjiang.Only when the sea surface temperature in the key region of the Indian Ocean was abnormally warmer in spring,the intensity of westerly jet increased at 200 hPa,the low value systems were active in western Siberia at 500 hPa,the extreme summer precipitation in the northwest region of northern Xinjiang was increased which cooperated with the water vapor transportation in the eastward path.

关 键 词：北疆 夏季极端降水 春季热带海温 环流特征 

分 类 号：P426.6[天文地球—大气科学及气象学]