北京上甸子站 PM2.5浓度与气象要素关系分析

摘要

In recent years,air pollution characterized with fine particulate matter (PM2.5 )as main air pollutant in Beijing had become an environmental issue of great concern.Based on PM2.5 monitoring data and various meteoro-logical data at Shangdianzi national meteorological station and regional air pollution background monitoring station in Beijing area in 2013,relationships between PM2.5 concentrations and meteorological conditions in this area were analyzed.The results show that meteorological elements have a significant impact on PM2.5 concentration in Beijing area.Among them,precipitation and sunshine duration have significant impact on PM2.5 concentration.Daily aver-age and maximum concentrations of PM2.5 are in a significantly decreasing trend with increasing precipitation and sunshine duration.On the other hand,relative humidity has also significant impact on PM2.5 concentration.PM2.5 concentration increases significantly with increase of relative humidity.There is an inverted U-shaped relationship between daily maximum wind speed and PM2.5 concentration.Lower wind speed causes increase of PM2.5 concen-tration,while higher wind speed promotes effectively diffusion of pollutants and reduces PM2.5 concentration.PM2.5 concentration is significantly lower in summer than in other seasons in Beijing area.%近年来，以细颗粒物（PM2.5）为主要污染物的北京地区大气污染已成为人们高度关注的环境问题。本文利用2013年北京市密云地区上甸子国家气象观测站和区域大气本底污染监测站 PM2.5监测数据和气象要素数据，分析了北京地区 PM2.5浓度与气象条件之间的关系。结果表明：北京地区气象因素对 PM2.5污染具有显著影响，其中降水、日照时数对 PM2.5浓度有显著的正相关关系，随着降水和日照时数增加，PM2.5日平均浓度和日最高浓度均呈显著下降；相对湿度对 PM2.5浓度有显著的负相关关系，随着相对湿度增加，PM2.5浓度显著上升；最大风速与 PM2.5浓度呈倒 U 型关系，较低的风速将导致 PM2.5污染增加，但风速达到一定级别时，可有效促进污染扩散，降低 PM2.5浓度。北京地区夏季 PM2.5污染水平显著低于其他季节。