Effects Of Different Types Of Aerosols On Ice Clouds At SACOL

The research on the influence of aerosols on the macro and micro quantities of ice clouds in Yuzhong can further understand the indirect effects of aerosols in semiarid climate areas and reduce the uncertainty of aerosols and ice clouds in semi-arid climate areas.In this paper,the relationship between ice clouds and aerosols at SACOL is studied by using KAZR cloud radar ground-based observation data and ice cloud identification data at SACOL,combined with ERA5 meteorological field reanalysis data and MERRA2 aerosol products.The aerosols are classified according to the contribution of each component,and are divided into eight categories in total.The aerosols of each category are analyzed and divided into two types of aerosols rich in dust and rich in sulfate.The relationship between the optical depth of each type of aerosol and the macro and micro parameters of ice clouds is discussed,combined with the analysis of the first principal component of the meteorological field,the conclusions are as follows:(1)The cloud top height and cloud layer thickness of ice clouds increase with the increase of the first principal component(PC1)of meteorological field,and increase with the increase of aerosol optical thickness(AOT).When the meteorological field is restricted,the correlation coefficients of ice cloud top height,cloud thickness and AOT decrease.(2)The thickness of the ice cloud corresponding to the sulfate-rich aerosol type is thicker,and its average thickness increases by 7.80% compared with the sand-dustrich aerosol type.The aerosols rich in sand and dust particles correspond to higher cloud top heights of ice clouds.Compared with the aerosols rich in sulfate,the average increase in cloud top height is 4.62%.(3)When the path of ice water is not restricted,the size of ice crystal particles increases with the increase of aerosol optical thickness.After using the partial correlation coefficient method,the aerosol-cloud interaction index(ACIr)analysis method,and the difference method to restrict the ice-water path,it is found that the increase of the aerosol optical thickness inhibits the increase of the ice crystal particles,and the range of the ACIr value is 0.013～0.067.(4)Different aerosols will lead to differences in the size of ice crystal particles.After using the difference method to limit the path of ice water,the ice crystal particles corresponding to the sulfate-rich aerosol type are smaller than the dust-rich aerosol.Changes in the meteorological field will lead to changes in the ACIr.After using the difference method to limit the path of ice water,the ACIr value when the difference of the first principal component(d PC1)is less than-0.40 is the ACIr value when d PC1 is greater than 0.40 1.6 times.