Analysis Of Distribution Characteristics And Sources Of Aerosols In The UTLS Of Asian Summer Monsoon Region

In this paper,we use the aerosol data from the 2006-2017 CALIPSO(V4.10)to analyze the distribution characteristics of aerosols in the UTLS of Asian summer monsoon region,and combine NCEP reanalysis data to study the impact of meteorological elements on aerosols in the UTLS region,and select a cases to analyze the UTLS aerosol sources and types of aerosols in Kunming.The main conclusions are as follows:(1)The aerosol total backscatter coefficient in the UTLS of Asian monsoon region in summer and winter are both of high in the south and low in the north,and there is almost no aerosol in the 18-19 km.At 13-18 km in summer,aerosols are mainly distributed south of 35°N,and high-value areas are mainly located on the land in the range of 70-110°E and 10-30°N.The aerosol total backscatter coefficient in winter is obviously shifted to the low latitude south of 20°N,and there is almost no aerosol in the middle part of the Asian continent.(2)The large-scale circulation in the Asian summer monsoon region is conducive to the upward transport of aerosol particles.The formation and distribution of aerosols in the UTLS region are caused by the combination of dynamic effects and the distribution of surface sources.The distribution of high values of the UTLS aerosol backscatter coefficient in the Asian summer monsoon region is related to the seasonal movement of South Asia High anticyclone circulation,and is located in the southeast of the anticyclone.In the weaker years of the South Asia High,the aerosol distribution of the relatively strong year is smaller and the location is southerly.(3)In the summer,the five sub-regions of the South Asia High anticyclone circulation have a high value area of total aerosol backscatter coefficient near 13-18 km.The North India is the largest region and the East China is the smallest region.In the winter,only slightly less aerosol layers exist in the South China at 13-16 km.The aerosol total backscatter coefficient profile corresponds well with the temperature and relative humidity profile,and the low temperature and high humidity environment can significantly enhance the aerosol scattering ability.In summer,the temperature of UTLS in North India is the lowest and the relative humidity is the highest.In winter,the temperature of UTLS in South China is the lowest and the relative humidity is the highest.(4)In the summer of 2014,15 km of aerosols in Kunming area mainly came from the southeast of the Qinghai-Tibet Plateau.Types of aerosols were dust aerosols,polluted continental aerosols,polluted dust aerosols,soot,and a small amount of clean continental air aerosols.