岳阳城区空气污染的变化特征及气象影响因素

Variation Characteristics and Meteorological Influencing Factors of Air Pollution Index in Yueyang

根据2003年12月至2013年12月空气污染资料,对岳阳城区空气污染的变化特征及气象影响因素进行了分析,探讨了2013年岳阳城区出现的典型空气污染过程的天气实况、大尺度环流背景及成因。结果表明:近10年来,岳阳城区API指数呈显著下降趋势。冬季空气污染最严重且年际变化较大,而夏季空气污染相对较轻且年际变化较小。1—12月API指数基本呈V形变化,且具有冬半年(10月至次年3月)偏高,夏半年(4—9月)偏低的变化规律。工业布局、主导风向、地理条件等导致岳阳城区空气质量具有显著的时空分布。气温日较差大、逆温等大气处于稳定状态下空气污染加重。本地气象和外地输入因素导致2013年岳阳城区出现一次比较典型的空气污染过程。用多元回归方法建立的API指数预报方程表明,气象要素和天气现象对岳阳城区API指数有显著影响。

Based on the air pollution index data from December 2003 to December 2013, the variation characteristics of air pollution in Yueyang, and the actual weather, large-scale circulation backgrounds, and causes of typical air pollution processes in 2013 in Yueyang are analyzed. The results show that API index reduced significantly in Yueyang in recent 10 years. The air pollution in winter was the most serious with big annual change, and relatively light and small in summer with small annual change. API index showed a V-shaped change from January to December, and monthly average API was higher in winter （from October to next March） and lower in summer （April to September）. The time and space distribution of air quality in Yueyang was influenced significantly by the industrial layout, dominant wind direction, and geographical conditions. The atmosphere in a stable condition, such as great diurnal range and temperature inversion, aggravated air pollution. Local meteorological and nonlocal input factors resulted in the typical air pollution process over Yueyang in 2013. Using the multiple regression method to establish the API index forecast equation, the results show that meteorological elements and weather phenomenon in Yueyang had a significant influence on API index.