天气形势对南昌市空气质量影响的初步分析

利用2007--2010年南昌市空气污染监测资料以及气象观测资料，分析了空气质量与天气形势的关系，以及造成南昌市空气污染的主要天气形势特征。结果表明：（1）南昌市空气污染具有明显的季节性变化特征，冬季污染日出现频次最高，其次是春、秋两季，夏季由于雨水的冲刷稀释作用、热对流作用，极少出现空气污染日。（2）影响南昌市空气质量的地面形势主要分为低压类（倒槽、锋前）和高压类（高压底部、高压后部、弱高压），而高空系统主要为槽后西北气流以及西南气流的影响。（3）当出现空气污染时，地面至1000hPa近地层逆温非常明显，地面风速弱，基本在3m／s以下，且以偏东风出现频次最高。（4）污染物浓度与霾天气密切相关，霾日的空气质量较差。

Preliminary study of the effect of synoptic situation on Nanchang air quality

Basing on 2007-2010 air pollution monitoring data of Nanchang, and general meteorological observation data, a statistical method is employed to analyze the relationship between air quality and synoptic situation. The results show that： （1） There is an obvious seasonal variation of air pollution in Nanchang. The pollution day occurs most frequently in winter, followed by those occur in spring and autumn, and no presence of air pollution in summer due to scouring and dilution effect of rainfall and heat convection; （2） The ground weather situations that affect air quality include two main types, i.e., low pressure type （e.g. inverted trough, front） and high pressure type （e.g. bottom of high pressure, back of high pressure, and weak high pressure） ; The upper weather systems include the northwest and southwest airflow of trough rear; （3） During the air pollution terms, there is an obvious thermal inversion close to ground, and weak ground wind speed is less than under 3 m/s, with more frequent easterly wind; （4） Pollution concentration has a high correlation with the appearance of haze.