风的气候变化对上海地区秋季空气质量的可能影响  

The Possible Effect of Climate Change on Air Quality During Autumn in Shanghai

作　　者：周伟东[1] 梁萍[2] 

机构地区：[1]上海市城市环境气象中心,上海200135 [2]上海市气候中心,上海200030

出　　处：《资源科学》2013年第5期1044-1050,共7页Resources Science

基　　金：上海市自然科学基金项目(编号:10ZR1427600);中国科学院战略性先导科技专项项目(编号:XDA05090204)

摘　　要：为探索气象要素的长期变化对空气质量的影响,本文以上海地区为例,利用该地区2002年-2010年秋季PM10浓度资料、1956年-2010年秋季风向、风速观测资料以及NCEP/NCAR再分析全球大气环流资料,分析了上海地区秋季PM10浓度变化特征及其与风向、风速的关系,并进一步探讨了风向、风速的长期变化对上海地区空气质量的可能影响。结果表明:上海地区秋季PM10浓度呈现明显下降的趋势,而风速、风向的长期变化对其有重要影响。PM10浓度与风速密切相关,静风时浓度最大,随着风速增大,PM10浓度逐步降低。风向对PM10浓度的影响也非常显著,近地面吹偏东风时PM10浓度相对较低。在以西太平洋副高强度增强趋势为主要代表的大气环流变化背景下,上海地区秋季近地面偏东风风速出现减弱趋势,但偏东风风向频率却明显增多。偏东风风向频率的增加有利于海上洁净空气向上海地区输送,从而改善该地区的空气质量。Air quality and pollution have become major issues in China. To explore the effects of climate change on meteorological elements and the subsequent impact on air quality, we used the PM 10 concentration and wind observation data for autumn 2002-2010 and 1956-2010 in Shanghai. We also used global atmospheric circulation data and NCEP/NCAR reanalysis for autumn 1956-2010. Results show that PM10 concentration during autumn in Shanghai has declined over the last decade, falling over a range of 32.4ug/m^3 in 2002-2010. PM10 is usually related to wind velocity. PM10 reached the maximum value of 68.2ug/m^3 under static wind conditions and PM10 concentration reduces with wind speed. Wind direction exerts distinct impacts on PM10. If wind speed fails by （1.0-2.0）m/s, the concentration of 30.4ug/m^3 is relatively low under easterly wind near the land surface, while those at 52.4ug/m^3, 63.9ug/m^3, 34.Sug/m^3 under southerly, westerly and northerly winds are 72%, 110%, 14% higher than that under static wind, respectively. The average wind speed during autumn in Shanghai has declined at 0.25m/s perl0y. The West Pacific subtropical high is a general circulation system that greatly influences dominant wind during autumn in Shanghai. Under climate change and the enhancement of West Pacific subtropical highs, the easterly wind frequency has increased and wind speed has decreased in Shanghai. More easterly wind transports more clean air from the sea to Shanghai, and this may be responsible for the marked improvement in air quality in Shanghai in recent years.

关 键 词：风向 风速 空气质量 污染 PM10 秋季 副高 上海 

分 类 号：P463.1[天文地球—大气科学及气象学]