汕头市气象干旱演变及其大气环流特征  

On the Meteorological Drought Evolution in Shantou and theCharacteristics of Associated Patterns of General Circulation

作　　者：李应龙 林禹光 林敏 杨如瑩 LI Ying-long;LIN Yu-guang;LIN Min;YANG Ru-ying(Meteorological Bureau of Shantou,Shantou 515041;Meteorological Bureau of Huilai,Huilai 515200)

机构地区：[1]汕头市气象局,广东汕头515041 [2]惠来县气象局,广东惠来515200

出　　处：《广东气象》2023年第2期39-43,69,共6页Guangdong Meteorology

摘　　要：利用汕头国家气象观测站2001年1月—2021年5月的逐日降水资料和美国国家环境预测中心/美国国家大气研究中心(NCEP/NCAR)月尺度风场、高度场的大气环流再分析资料,采用相关、合成分析的方法研究了汕头干旱事件的时空变化特征,探讨干旱事件的成因。结果表明:(1)汕头气象干旱事件以秋冬和秋冬春为主;一年四季都可能会出现干旱事件,但多数发生在9月至翌年3月,以秋冬连旱为主。(2)无论是干旱事件的频率还是强度,都显示出近几年来汕头干旱事件的严重,并具有明显的发展趋势。(3)汕头地区旱年时,不同季节环流差异较大,其中春季阿留申低压增强,冷空气驻留在大陆中高维度地区,华南地区更易受高压控制,气温偏高降水偏少;秋季内蒙的高压增强,冷空气在大陆中高纬度地区活动比较频繁;冬季极涡增强,广东地区的低层西南风偏强,由于没有冷空气配合气温偏高,降水偏少。Using the daily rainfall data from a national meteorological observation station in Shantou and the general circulation reanalysis of monthly wind fields and geopotential heights from NCEP/NCAR for the period from January 2001 to May 2021,this work studies the spatiotemporal variation characteristics of the city's meteorological droughts and discusses their causation with the methods of correlation and composite a⁃nalysis.The results are shown as follows.(1)The meteorological droughts of Shantou took place mainly in autumn through winter and from autumn,winter to spring.Although drought events could happen in all sea⁃sons,most of them were from September to the succeeding March and lasted continuously from autumn to winter.(2)It is shown that the drought events of Shantou were getting serious over the past few years and tended to develop significantly,either in frequency or intensity.(3)For the drought years of the Shantou ar⁃ea,the circulation differed much with the season.In spring,the Aleutian low intensified and cold air main⁃tained over the mid⁃and high⁃latitudes of the Eurasian continent,making it more likely for south China to be dominated by high pressure such that the air temperature was relatively high and the precipitation was rela⁃tively little.In autumn,a high pressure became stronger in the Inner Mongolian Autonomous Region and cold air was more active over the mid⁃and high⁃latitudes of the Eurasian continent.In winter,a polar cold vortex got stronger and low⁃level southwesterly enhanced over the region of Guangdong,resulting in relatively high temperature and little precipitation due to the lack of cold air activity.

关 键 词：气候学 干旱 大气环流 汕头 

分 类 号：P46[天文地球—大气科学及气象学]