Study On Optimization And Inspection Of Diagnosing Three Dimensional Cloud And Cloud-Water Region In China And Global

Cloud water as an important part of the atmospheric water cycle plays a key role in climate change,weather analysis and artificial weather.In the past,there have been few studies on the diagnosis of three-dimensional cloud and cloud water region.This paper based on the diagnosis methods of three dimensional cloud and cloud-water region in China proposed by Cai miao et al,joining with CloudSat/CALIPSO data to identify the cloud,and according to the vertical temperature stratification,optimized the cloud discriminant threshold and its vertical profile,which is applied to the diagnosis of three-dimensional cloud region,and compared with the satellite and other cloud data.At the same time,the global cloud distribution characteristics and the globally applicability of three dimensional cloud and cloud-water region diagnosis methods have been discussed.The main conclusions include:1 TS score and correct rate of cloud region diagnosis using the optimized relative humidity threshold method are generally higher than that of using the original method.The position of cloud and cloudless in Heilongjiang region and Xinjiang region diagnosed by the optimized relative humidity threshold are more corresponding to the measured results,The cloud vertical direction diagnosed by the optimized relative humidity threshold is is also more consistent with satellite and ground observation,which the identification of cloud top and cloud base is better than the original method.The optimized vertical profile of water content and particle effective radius is more advantageous to distinguish the phase of the particle,and reduces the impact of the terrain.2 The frequency of clouds in ocean,land area,with the temperature of the decrease,appears first increase after the decrease in the trend of change.The global average total cloud cover by CloudSat/CALIPSO Joint detection is about 0.69.Joined the CALIPSO cloud observation data,the cloud amount in most region has increased.CALIPSO observed mainly ice clouds in the-60?-40 ? temperature range of-ITCZ and the southern hemisphere near 60°S westerlies and the north Pacific storm track belt area,warm cloud in 10?20? temperature range of California and west coast of Peru,and cloud of supercooled water in-10??0? temperature of the southern hemisphere near westerlies.3 Using diagnosis methods of three dimensional cloud and cloud-water region,identification of warm clouds and mixed clouds in ocean areas are generally better than that in land.The results which used diagnosis method of the global three-dimensional cloud region are consistent with ECMWF data and CERES cloud observation data in terms of the distribution of cloud in each level,but generally larger in value.lt is found that the LWC in the global land and sea area are the most abundant at low temperature,and decrease with the decrease of temperature,all of them are less than 0.35g/m3,while in the high temperature the LWC of ocean area is slightly larger than that of land;The IWC is smaller than the 0.13g/m3,IWC with the increase of the height of the first decrease after the increas'e in the last reduction of the trend of change,the maximum value of-20 ?;the whole layer of liquid phase particle effective radius is about 11 ?m.The mean value of th e ice phase particles effective radius is between 40 and 120?m,and decreases with the decrease of temperature.