不同冷暖背景下影响云南冬季温度异常的环流特征  

Circulation characteristics influencing winter temperature anomalies in Yunnan during cold and warm periods

作　　者：马思源 晏红明[1] 杨鹏武[1] 罗蒙 MA Siyuan;YAN Hongming;YANG Pengwu;LUO Meng(Yunnan Climate Center,Kunming 650034,China)

机构地区：[1]云南省气候中心,昆明650034

出　　处：《气象科学》2024年第6期1072-1083,共12页Journal of the Meteorological Sciences

基　　金：国家自然科学基金资助项目(U1902209);云南省基础研究专项重点基金资助项目(202201AS070069)。

摘　　要：利用1961—2019年云南省122站逐月气温、ERA5再分析和大气环流指数等资料,首先分析了云南省冬季气温的变化特征,表明云南冬季气温存在显著的增暖趋势,1996年的暖突变之前为冷期,之后为暖期。进一步分析冷期和暖期背景下冷、暖异常年的环流差异,发现不同背景下冷(暖)事件发生时大气环流存在显著差异,表现为暖期背景下冷事件(WC)发生时东亚东部强冷空气活动特征比冷期背景下的冷事件(CC)显著,而冷期背景下暖事件(CW)发生时呈现的冷空气偏弱和西南暖湿气流偏强的特征比暖期背景下暖事件(WW)显著,即暖期背景需要更强的冷空气活动才能引发冷事件,冷期背景下需要来自热带更强的西南暖湿气流才能引发暖事件。高原高度场、印缅槽强度对云南冷、暖期冬季平均气温均有明显的指示意义。Using the monthly temperatures data of 122 stations in Yunnan Province from 1961 to 2019,the ERA5 reanalysis data,and atmospheric circulation indices data,the characteristics of winter temperature variation characteristics in Yunnan were analyzed.Results indicate that there is a very significant warming trend for winter temperatures in Yunnan,with an abrupt warming in 1996.Further analysis of the circulation differences between anomalously cold and warm years during cold and warm periods reveals significant differences in the atmospheric circulation during cold(warm)eventsin different periods,indicating that the characteristics of strong cold air activity in eastern East Asia during cold events in the warm periods(WC)are more significant than those of cold events in the cold periods(CC),while the characteristics of weak cold air and strong southwest warm-wet airflow during warm events in the cold periods(CW)are more significant than those of warm events in the warm periods(WW).The warm period requires stronger cold air activity to generate the cold event,whereas the cold period requires stronger southwest warm-wet airflow from the tropics to trigger the warm event.During both cold and warm periods,the height field of the plateau and the strength of the Indo-Burmese trough are major indications of the mean winter temperatures in Yunnan.

关 键 词：暖突变 冷期背景 暖期背景 云南冬季温度异常 大气环流差异特征 

分 类 号：P423[天文地球—大气科学及气象学] P434