Research On Properties And Measurement Methods Of Atmospheric Aerosol In Typical Area

The changes of the composition and distribution of the atmospheric aerosol cause the change of the average net radiation flux in the troposphere,which produces the radiative forcing effect.The impact of aerosols on the atmosphere radiation is considered to be one of the most important and uncertain aspects of climate change prediction.Therefore,it is of great significance to accurately measure the physical parameters of atmospheric aerosols in order to evaluate the radiation effects and climatic effects.The aerosol spectral distribution in the East China Sea and South China Sea and coastal areas,the Pacific and Indian Ocean waters were statistically analyzed.The number density,particle size distribution and the extinction characteristics of marine aerosol were obtainend.Micro Pulse Laser radar used for detecting aerosol,in combination with particle counter,visibility instrument and particle mass concentration detector,carried out the study of the distribution of aerosol mass concentration in the horizontal path.A dual channel aerosol mass concentration detector was developed to measure the mass concentration of atmospheric aerosol in real time.The seasonal transformation characteristics of aerosol optical depth and vertical extinction profile in typical area of China were analyzed.The main research achievements and innovations of this thesis are as follows:(1)During August 2004 to March 2016,particle size distribution of atmospheric aerosol in the East China Sea and South China Sea and coastal areas,the Pacific and Indian Ocean waters were statistically analyzed and fitted,the distribution characteristics of aerosol particle in each sea were obtained,and the effects of meteorological parameters on aerosol particle size distribution were analyzed.The statistical results were given.Study in depth on the optical transmission characteristics of marine aerosol,and found that the extinction characteristics of the aerosol in the 1-3?m bands were not affected by the wavelength under the condition of strong wind.(2)A method for calculating the distribution of aerosol mass concentration in the horizontal is proposed.Though scanning,system is able to detect the pollution source within a path of 6 km,resolution up to 30 meters.The reliability of the method is verified by the comparison to particle mass concentration detector.Compared with the limited base-point monitoring,the inversion algorithm has the advantages of large monitoring range and high resolution,the planar scanning monitoring can be carried out on the specific area,and the distribution information of the near surface aerosol can be obtained.The distribution characteristics of the pollution sources,the spatial and temporal change information and the transmission path are analyzed,which provide effective data support for the prevention and control of urban aerosol pollution.(3)The source and transport pathway of aerosols is an important subject of atmospheric aerosol research,and there is a certain correlation between the type of aerosol and the chemical composition of particle source and the distribution of particle size distribution.The atmospheric aerosol mass concentration detector is developed,which can directly measure the mass concentration of atmospheric aerosol particles,and afford samples for subsequent chemical composition analysis and absorption characteristics analysis,thus providing data support for the study of the source and composition of aerosol particles.(4)By using meteorological visibility and other data of 120 sites nationwide in 2009-2013 years,atmospheric aerosol optical depth of the whole layer is retrieved and the vertical profile of atmospheric aerosol extinction coefficient is calculated.The seasonal average value of visibility,atmospheric aerosol optical thickness and vertical extinction profile in typical area of China were analyzed in 2009-2013 years.