近20年来我国夏季强对流云顶气压的空间分布及变化趋势

Spatial Distribution and Variation Tendency of Summer Convection Cloud-Top Pressure over China in Recent 20 Years

利用ISCCP(International Satellite Cloud Climatology Project)最新的D2云气候资料集,分析了1988至2007年6-8月我国云顶气压的空间分布及变化趋势,并结合中国气象局国家气象信息中心发布的中国均一化历史气温、相对湿度和大气压强数据集,进行了相关分析,讨论了其变化成因。结果表明:近20年来我国夏季强对流云顶气压在青藏高原、新疆天山地区、甘肃、云南、两广沿海、四川中西部和内蒙古中部较低,云顶发展较高。新疆天山以北和华北地区的变化趋势最明显,其中,新疆天山以北地区云顶气压降低,云顶高度升高,主要与该地区变暖变湿有关;而华北地区云顶气压升高,云顶高度降低,这很可能是由于该地区气溶胶含量的增加造成的。

Based on the latest ISCCP （International Satellite Cloud Climatology Project） D2 cloud climate data, with the historical homogenization temperature, relative humidity and atmospheric pressure from National Meteorological Information Center, the spatial distribution and the variation tendency of cloud-top pressure over China during June to August from 1988 to 2007 was analyzed. The results show that in Tibeten Plateau, Xinjiang Tianshan Mountains, Gansu, Yunnan, Guangdong and Guangxi coast, central and western Sichuan, central Inner Mongolia, cloud-top pressure is low and cloud-top height develops high. The northern Tianshan Mountains in Xinjiang and North China show the most obvious variation tendency with cloud-top pressure reducing and cloud-top height rising in the northern Tianshan Mountains in Xinjiang. cloud-top pressure has good correlation with temperature and specific humidity. On the contrary, the rise of cloud-top pressure and the reduce of cloud-top height in North China are possibly relative to the increase of aerosol.