东北地区春季沙尘天气变化特征及其与大气环流变化的关系  

Characteristics of sand-dust events and their relationships with atmospheric circulation in spring in Northeast China

作　　者：杨雪艳 张丽[1] 袭祝香[2] 刘玉汐 徐士琦 张晨琛[1] YANG Xue-yan1, ZHANG Li1, XI Zhu-xiang2, LIU Yu-xi2, XU Shi-qi1, ZHANG Chen-chen1(1. Jilin Climate Center, Changchun 130062, China; 2. Jilin Meteorological Observatory, Changchun 130062, China)

机构地区：[1]吉林省气候中心,吉林长春130062 [2]吉林省气象台,吉林长春130062

出　　处：《气象与环境学报》2018年第4期75-83,共9页Journal of Meteorology and Environment

基　　金：吉林省节能减排应对气候变化及生态文明建设项目(201401);吉林省环保厅环境保护科研项目(吉环科字2016-20)共同资助

摘　　要：利用1961—2016年东北地区72个气象站沙尘天气观测资料以及NCEP/NCAR再分析资料,分析了东北地区春季沙尘天气的时空变化特征、气候趋势及突变特征及大气环流对沙尘天气频次的影响。结果表明:1961—2016年东北地区春季沙尘天气日数具有西部多东部少、平原多山地少的地域分布特征;东北地区春季沙尘天气以及扬沙、沙尘暴、浮尘均呈显著减少趋势;沙尘天气日数在1985年前后发生突变,突变后沙尘天气平均日数较突变前减少了3 d。当500 hPa距平场上贝加尔湖及中国东北地区大部分地区为负距平区、巴尔喀什湖附近为正距平中心,且地面西伯利亚高压面积偏大、位置偏东,中国西北、华北地区气压比常年偏低时,东北地区沙尘天气异常偏多;当贝加尔湖及中国大陆的大部分地区为正距平,贝加尔湖附近为正距平中心,且地面西伯利亚高压面积偏小、位置偏西,中国北方大部分地区气压比常年偏高时,东北地区沙尘天气异常偏少;56 a来北半球极涡面积和亚洲区极涡面积减少以及极涡强度减弱,是导致东北地区春季沙尘天气减少的原因之一。Based on the observational data of sand-dust events at 72 meteorological stations and the National Centers for Environmental Prediction/National Center for Atmospheric Research（ NCEP/NCAR） reanalysis data in Northeast China from 1961 to 2016, the spatiotemporal characteristics,climatic trends and abrupt change characteristics of sand-dust events in spring over Northeast China were analyzed,and the effect of atmospheric circulation on frequency of sand-dust events was investigated. The results show that the number of sand-dust events is greater in the western region of Northeast China than the eastern region and in plain areas than mountainous area. The sand-dust events,blowing sand events, sandstorm events,and floating dust events in springs from 1961 to 2016 in Northeast China decrease obviously. The number of sand-dust days change abruptly around 1985. After 1985, the mean number of sand-dust days is 3 d less than before. Sand-dust events in the Northeast China occur more frequently for the following conditions,firstly,when the geopotential height anomalies at 500 hPa above the Baikal Lake and most parts of Northeast China are negative and those nearby the Balkhash Lake are positive; secondly, the occupation area of Siberian High is larger and its location shifts eastward; and thirdly, the air pressure in the Northwest China and North China is lower than the normal conditions. However, sand-dust events in the Northeast China occur less frequently when the geopotential height anomalies at the Baikal Lake and in most parts of mainland in China are positive with the center of positive anomaly area near the Baikal Lake, the surface area of the Siberian High is smaller and its location shits westward,and the air pressure in the most northern regions of China is higher than normal. The reduction of the polar vortex area in the northern hemisphere and in Asia and the decrease in polar vortex intensity in the past 56 years is one of the reasons for the decrease in sand-dust events during spring in Northeast China.

关 键 词：东北地区 沙尘天气 气候变化 大气环流 极涡 

分 类 号：P425.55[天文地球—大气科学及气象学]