论文部分内容阅读
利用2007-2010年和2013-2014年CloudSat卫星资料,分析了中国11个地理区域的深对流云发生率、冰/液态水路径、冰/液态水含量等分布特征及其季节变化.结果显示,深对流云发生率整体呈现从东南到西北递减的趋势,高值区主要集中在西北地区东南部、西藏东南部、西南地区东部和南部、黄淮西部和南部、江汉、江淮、江南和华南等地,就各个地区不同季节而言,江南地区夏季的值最大,达到10.34％.在垂直高度上,深对流云发生率分布在18km以下,最大值为11.31％,出现在江南夏季4.08～4.56km高度上.深对流云中冰水路径最大值出现在华南夏季,液态水路径最大值出现在黄淮秋季,西藏地区的深对流云中冰水路径的比例明显高于液态水路径.冰水含量在垂直高度上存在两个高值区,分别位于6～8km、14～18km,最大值发生在江南夏季19.44km左右高度上,达到1018.87mg·m-3,季节差异较大的高度位于14～18km.液态水含量最大值发生在江淮冬季,达到411.50 mg·m-3,高度在9.36km左右,垂直高度上最大值在2～6km上均有出现.该结果可以更好地揭示深对流云的气候特征,并为人工影响天气以及数值模式中对深对流云物理量的模拟提供一定的参考依据.“,”The deep convective clouds are important regulators of the earth-atmosphere system and also closely relate to the formation of many extreme weathers such as downbursts,storms and lightning.The measurement of cloud profile radar (CPR) from CloudSat has the advantage in detecting the accurate properties in deep convective clouds in different altitudes.The spatial and temporal variations of the probability and cloud microphysical properties in deep convective clouds,for exemple,the ice water content (IWC),liquid water content (LWC),ice water path (IWP) and liquid water path (LWP),were analyzed across eleven sub-regions in China based on the CloudSat dataset during 2007-2010 and 2013-2014.The results indicate that the probability of deep convective clouds decreased from southeast to northwest parts generally.The high values were mainly concentrated over the southeast of Northwest China,the southeast of Tibet,the east and south of Southwest China,the west and south of Huanghuai,Jianghan,Jianghuai,Jiangnan,and South China.Generally,it can be demonstrated that the deep convective clouds are more likely to occur in summer.For each area in different seasons,the highest value of the probability of deep convective clouds in total altitudes was 10.34％ over Jiangnan in summer.The value of probability was much larger over Jiangnan,Jianghan,Jianghuai or Huanan than other areas,while it was lower over Northwest China.Moreover,among the different altitudes,the probabilities were located below 18 km and the maximum reached 11.31％ at roughly 4.08～4.56 km over Jiangnan.The maximum value of IWP and LWP occurred over South China in summer and Huanghuai in autumn,respectively.Over Tibet,the value of IWP was much larger than that of LWP in the deep convective clouds,because the average altitude of Tibet was relatively high and the ice clouds were formed much easily than liquid clouds.Vertically,the maximum IWC with a magnitude of 1 018.87 mg · m-3 occurred near the altitude of 19.44 km over Jiangnan in summer.Two peaks of IWC were detected at 6～8 km,and 14～18 km where the significant seasonal difference occurred.In addition,the maximum LWC was 411.50 mg · m-3at the altitude of 9.36 km over Jianghuai in winter and the peak of LWC in the vertical height occurred from 2 km to 6 km.The results in this work can explain climatic features of deep convective clouds and provide an observational basis for weather modification and simulations of deep convective clouds in models.