Integrated Analysis Of Typhoon Cloud System,Boundary Layer And Aerosol Physical And Optical Characteristic Variation From Remote Sensing Dataset

It seems that nowadays the research of the exploration techniques and detection instruments has become a more and more important aspect of atmospheric sciences.In order to obtain the accurate parameter of the whole atmosphere layer,the integrated utilization of the detection method should be applied in a certain area.Satellite remote sensing has a wide spatial coverage while the ground-based observations can provide a time continuous dataset.The observations of the cloud and aerosol have always been the foundation for the weather forecasting,climate change and environment transition.Comprehensive utilization of the ground-based and satellite remote sensing method can create a very advantageous condition for the study of the cloud and aerosol.In this paper,remote sensing data from TRMM,MODIS,CALIPSO and ground-based data from CMA vertical radio-sounding will be used to provide us with the cloud optical properties of the tropical cyclone(TC)making landfall in China in recent years,the variation of planetary boundary layer(PBL)influenced by the TC and the difference of the aerosol characteristics in two heavy pollution processes.The main content is as follows:(1)We report a new perspective of optical properties of TC cloud system by using the MODIS and TRMM data over years from 2010 to 2014 for the 35 TCs in East Asia.We investigate the spatial distribution properties of the cloud-top height,the radar reflectivity,the polarization corrected temperature in 85.5GHz,hydrometeor vertical profile,cloud water path,cloud optical thickness,and the droplet effective radius in the development,maturity,and decay stages.The results indicate the significant differences of cloud characteristics in the maturity stage in comparison with the other two stages.Expect for the cloud effective radius,the other optical properties always have the prominent features in eye wall than the other structures of the cloud system.Influenced by the aerosols around the tropical cyclone cloud system,the effective radius in the development stage is larger than the other two stages.In addition,based on these quantified results,several ideal fitting equations and the models are constructed to reflect the properties of TC cloud system.A case study is analyzed to examine the accuracy of the quantified mean state for different stages of cloud properties and it reflected the model has the applicability to a single tropical cyclone.(2)The high spatial and temporal resolution of L-band radio-sounding data are in acquisition to help us discover the variation of PBL characteristics when attacked by TCs in eastern coastal China.Influenced by the TC,the meteorology elements such as temperature,relative humidity and the wind field always have a drastic change.The virtual potential temperature method,Holzworth method and bulk Richardson number method are applied as independent measurements of the PBL height(PBLH)estimation.Data analysis shows that the PBLH produced by these methods always varies in several hundred meters and they tend to distinct from each other in different focus like kinetic or thermodynamic theory.The virtual potential temperature method always produces the lowest PBLH among these methods.Only the extent of vertical mixing and the ground surface temperature are considered in the Holzworth method,and the landfall of TC could lead to temperature falling in the PBL therefore the PBLH will decrease.The importance of horizontal mixing in atmospheric dispersion and the dynamic process are emphasized in bulk Richardson number method and it can make the PBLH increase when TCs make landfall.(3)We select two heavy pollution processes in December 2015 in China.The result from the HYSPLIT trajectory model shows that the aerosol did not transfer from Beijing,Tianjin and Hebei(BTH)to Yangtze River delta(YRD)in the first pollution process.However,in the second pollution process,the aerosol could be brought from BTH to YRD through the north wind.We also use the MODIS and CALIPSO data to discover the distinction of the aerosol optical properties in the two processes.Although they have the similar aerosol optic depth,only the small size particulate can be transfer from BTH to YRD.In addition,the larger size particulate always has irregular shape and weaker backscatter coefficient compared to the small size particulate.The ground-based dataset also indicate that the transmission from BTH to YRD lead to the particulate content decreasing in Beijing and increasing in Jinan and Nanjing.In conclusion,the integrated analysis of ground-based and satellite remote sensing data is crucial not only to the weather forecasting and climate prediction,but also to the research of the TC and heavy pollution process.