库尔勒市春季沙尘天气重污染日变化特征及天气驱动成因  

Diurnal Variation Characteristics and Driving Force of Urban Heavy Dust Pollution in Spring in Korla

作　　者：周雪英[1] 温春 顾军明 谭俊 张仕明[1] ZHOU Xue-ying;Wen Chun;Gu Jun-min;Tan Jun;Zhang Shi-ming(Bayingolin Mongol Autonomous Prefecture Meteorological Observatory,Korla Xinjiang 841000,China;Korla Meteorological Bureau,Korla Xinjiang 841000,China)

机构地区：[1]新疆巴音郭楞蒙古自治州气象局,新疆库尔勒841000 [2]新疆库尔勒市气象局,新疆库尔勒841000

出　　处：《干旱环境监测》2022年第2期63-69,共7页Arid Environmental Monitoring

摘　　要：本文利用2014—2020年库尔勒市春季逐时大气颗粒物浓度、气象观测数据以及NCEP再分析资料,对沙尘天气重污染日和重污染过程进行统计和天气学诊断。结果表明:近7 a库尔勒市春季优良日呈显著增加,污染日和重污染日显著减少。沙尘重污染过程中AQI指数强度与能见度呈显著负相关,<1 km的低能见度强沙尘污染夜间发生频次高于白天;沙尘重污染过程风向与春季明显不同,白天朝南风方向转变、夜间朝东风方向转变。沙尘重污染过程颗粒物输送机制包括东南风辐合型多发生在槽后脊前的经向环流中,呈外地输入型沙尘污染;偏西风型多为槽前西风气流影响也为外地输入型沙尘污染;风向转换型发生在南北两支高空急流合并,地面冷空气强大背景下,先发生本地型沙尘污染,而后转为外地输入型沙尘污染,往往造成的污染持续时间长、颗粒物浓度高。Based on hourly atmospheric pollutant concentration,meteorological observation data and NCEP reanalysis data from 2014 to 2020 in Korla city,the heavy dust pollution days and heavy dust pollution processes were statistically and synoptic diagnosed.The results showed that in recent 7 years,the good days increased significantly,while the pollution days and heavy dust pollution days decreased significantly.In the heavy dust pollution process,AQI index intensity was negatively correlated with visibility,and dust pollution with low visibility less than 1 km occurred more frequently at night than in the daytime.The wind direction of heavy dust pollution process is obviously different from that of spring,changing to south wind direction in daytime and east wind direction in night.Most of the westerly wind is the west wind flow in front of the trough and also the dust pollution from outside.Wind direction conversion occurs when two upper-air jets from the north to the south merge and the surface cold air is strong.Local dust pollution first occurs,and then it turns into imported dust pollution,which usually results in long pollution duration and high pollutant concentration.

关 键 词：库尔勒市 春季沙尘重污染 日变化 颗粒物输送 

分 类 号：X51[环境科学与工程—环境工程]