南京市大气PM_(10)浓度的估算模型研究

以南京市为例,利用空气污染指数API、气象数据和TERRA/AQUA卫星气溶胶光学厚度(AOD)产品,分析了南京市PM_(10)浓度的变化规律,在PM_(10)浓度与气象要素进行相关分析的基础上,初步建立了基于气象要素和AOD的PM_(10)浓度估算模型。结果表明,南京市PM_(10)浓度在每年11,12月或1月最高,7,8月最低,季节性变化表现为冬春季浓度最高,秋季其次,夏季最低,PM_(10)浓度有逐年下降的趋势,但年均值仍高于国家II级标准;除了大气混合层高度外,PM_(10)浓度与大气压、风速、气温、相对湿度、水汽压、能见度、气溶胶光学厚度都有较好的相关性;基于气象要素的PM_(10)浓度估算模型的绝对系数R~2为0.510、平均相对误差为26.04%,基于AOD的PM_(10)浓度估算模型以TERRA和AQUA卫星AOD平均值构建的最佳,绝对系数R~2为0.482、平均相对误差26.11%,两种模型对PM_(10)的预测预报具有一定的指示意义。

Study on Estimated Model of PM10 Concentration in Nanjing City

Taking Nanjing city as an example ,using air pollution index API ,meteorological data and aerosol optical depth AOD retrieved by MODIS images of TERRA and AQUA satellite ,the variations of PM10 concentration are analyzed ,the rela-tionship of PM10 concentration and meteorological factors is discovered and the elementary estimated models of PM10 concen-tration are deduced based on the meteorological factors and AOD .The results show that the primary pollutant is PM10 ,the air quality grade is fine and the air quality trends to better in Nanjing ,that PM10 concentration is the highest in every Jan-uary ,November and December while it is the lowest in every July and August ,that is the highest in Winter or Spring ,sec-ond in Autumn and lowest in Summer ,and it trends to decrease ,but the annual average is still above the second level in na-tional standard ,that PM10 concentration has a good relationship with atmospheric pressure ,wind speed ,surface atmospheric temperature ,relative humidity ,water vapor pressure ,visibility ,AOD except for atmospheric mixed layer height .For PM10 concentration estimated model based on meteorological factors ,its determined coefficient ( R2 ) is 0 .510 and the mean rela-tive error (MRE) is 26 .04% .For that based on AOD ,the model deduced from the average AOD of TERRA and AQUA is the best ,in which R2 is 0 .482 and the MRE is 26 .11% .Two models will play an instructive role in PM10 concentration monitoring .