天津市秋季典型环境污染过程个例分析

摘要

选择天津市秋季典型PM10污染过程2010年10月3—12日环境空气质量监测资料和常规气象资料、探空资料及NCEP资料,研究大气环境天气背景场、大气层结稳定度的特征及其对污染过程的影响。结果表明：高低空环流背景场与污染过程密切相关。在污染上升阶段,层结稳定度迅速增加,500 hPa高空处于槽前,地面在华北地形槽中,高低空风速辐合;在污染峰值阶段,层结稳定,逆温层加强,环流场稳定少变,地面风力微弱;在污染下降阶段,层结稳定程度骤降,地面冷锋和高空槽过境,降水出现,高低空偏北风增大。同时,PM10污染过程与多项层结稳定度参数显著相关,与对流凝结高度单相关系数为0.84,因此,高低空环流背景场的配置和层结稳定度变化是PM10污染出现的主要原因。%Based on the environmental air quality monitoring data,the conventional meteorological data,the sounding data and the NCEP reanalysis data,a typical pollution process in Tianjin during October 3-12,2010 was analyzed.The synoptic background field of atmospheric environment,the atmospheric stratification stability and its effect on the pollution process were discussed.The results indicate that the pollution process is closely relative to the upper and lower environmental background fields.During the increasing stage of pollution concentration,the stratification stability increases rapidly,and the upper level situation field at 500 hPa is located in the front of the trough,the surface situation field is in the topographic trough of North China,and the upper and lower wind speed converges.During the stage of pollution concentration summit,the atmospheric stratification and the environmental background are stable,the inversion layer is strong,and the surface wind is weak.During the decreasing stage of pollution concentration,atmospheric stratification becomes unstable quickly;the surface cold front and upper trough pass over Tianjin area,precipitation occurs and the upper and lower north wind are enhanced.Meanwhile,PM10 pollution process is significantly correlated with multiple stratification stability parameters and its correlation coefficient with convective condensation level is 0.84.As a result,the configuration of upper and lower environmental background and the variability of atmospheric stratification are the main reasons causing the PM10 pollution.