摘要
利用2012年4-6月南京溧水野外观测站近地层微气象、地表辐射和通量交换数据,结合南京大学地球系统区域过程综合观测研究站(SORPES-NJU)的PM2.5质量浓度以及环境保护部发布的逐日API资料,使用聚类分析、合成分析和个例分析的方法,定量分析了南京地区不同大气污染程度下气象要素和地表能量平衡的响应特征.结果表明,观测期间南京地区污染天盛行偏南风,且风速较清洁天气低约30%.气溶胶白天对到达地面的太阳辐射的削弱作用大于对地面有效辐射的减弱作用,使得地面净辐射减小(日均值约46.3 W·m-2).气溶胶减弱感热通量、潜热通量,并影响二者在能量平衡中的比重.个例分析表明气溶胶通过减小白天地面净辐射,减弱地气系统能量,导致近地层气温降低(最大差值约1℃),湍流运动减弱,从而进一步抑制污染物的扩散,形成空气污染-地表能量收支-边界层结构间的正反馈过程.
Aerosols contribute substantially to radiative forcing,which inevitably influences the land surface process and then exerts a perturbation on climate.The interaction of meteorological characteristics,energy budget and aerosols over Yangtze River Delta has been investigated,by analyzing the concentration of fine particles collected from the Xianlin ‘flagship’central site of the Stations for Observing Regional Processes of the Earth System （SORPES）and meteorological parameters,radiation fluxes obtained from the Lishui subsidiary site of SORPES from April to June 2012.The results indicate that air pollution in this area is associated with southerly wind characterized by low speed.Heavy load of aerosols resulted in a decrease in the solar radiation by 64.8 W·m-2 and a decrease in the net radiation by 46.3 W·m-2 in the daytime.Weakened latent fluxes and sensible fluxes are observed combined with a changed Bowen ratio.It is speculated that aerosols reduce the net radiation and cause a decrease in air temperature near surface,which depresses the land surface turbulent fluxes and leads to an increase in aerosol con-centration in turn.
出处
《南京大学学报（自然科学版）》
CAS
CSCD
北大核心
2014年第6期800-809,共10页
Journal of Nanjing University（Natural Science）
基金
973项目(2010CB428503)
教育部“新世纪优秀人才支持计划”
江苏省博士生创新项目
国家人才培养基金(J1103410)
关键词
城市群区
气溶胶
气象要素
地表能量收支
city cluster yangtze river delta
aerosol
micrometeorological
energy budget
