湖北省2008年酸雨特征及成因分析

利用湖北省1999～2008年酸雨监测资料及相关气象环境资料,采用数理统计和对比分析等方法,对湖北省2008年酸雨特征、历史变化趋势及成因进行了分析,研究将有助于掌握湖北省酸雨发展形势及防治工作的开展。分析结果表明:湖北省2008年大部为强酸雨区,年均降水pH值为4.17,年酸雨发生频率为78.9%,年强酸雨发生频率为42.1%,年均降水K值为50.9μs/cm,并呈现出明显的季节性变化规律。以武汉和宜昌为代表站的酸雨历史比较发现,自1999年以来,酸雨强度和发生频率均有大幅上升。结合相关气象环境要素进行成因分析,发现大气SO2浓度与酸雨强度相关性较大,降水强度为中雨时酸雨强度和发生频率较大,降水前出现逆温有利于酸雨强度及发生频率的升高,850hPa风向对酸雨也存在不同程度的影响。

Feature and Cause Analysis on Acid Rain of 2008 in Hubei Province

Based on the observed data of acid rain from 1999 to 2008 and relevant meteorological and environmental data,mathematic statistics and contrast analysis method were used to analyze the feature and cause on acid rain of 2008 in Hubei Province and change trends in recent years.Results showed that most area of the Province is the strong acid rain area,with average pH value of precipitation 4.17,annual frequency of acid rain appearance 78.9%,frequency of strong acid rain appearance 42.1% and average conductance 50.9μs/cm,which present obvious seasonal variation regularity.By analysis of historical data of acid rain of Wuhan and Yichang as representative,it was found that the strength and frequency of acid rain have increased significantly since 1999.Based on relevant meteorological and environmental factors to analyze the cause of acid rain,it was found that the strength of acid rain is highly related to concentration of SO2,and strength and frequency of acid rain are high when there is moderate rain,and inversion happened before precipitation is advantage to enhance the intensity and frequency of acid rain,and different wind directions in 850hPa have different affections to acid rain.