中文摘要：

利用2011年7月1-31日在青藏高原北侧民丰站进行加密探空观测获取的高空气象资料,分析了民丰夏季大气结构和塔里木盆地南缘上空的水汽特征。结果表明：（1）受青藏高原地形热力影响,民丰夏季对流层高度可达到16 000m以上,其绝对高度与珠峰地区对流层绝对高度相近;0℃层高度约为3 450m,略低于珠峰地区。（2）夏季副热带西风急流在青藏高原北侧表现强劲,呈东西向分布,厚度约为12 000m,最大风速中心带位于10 700～11 400m高度,最大风速达到45m.s-1以上。（3）受副热带西风急流底部西风和西西南风影响,夏季青藏高原西北部上空的水汽被输送到塔里木盆地南缘,若羌、民丰及和田站上空3 000～7 500m高度存在湿度大值层,平均相对湿度在60%～70%之间,最大湿度可达到85%以上。（4）民丰夏季白天对流边界层可达到3 200m高度,夜间稳定边界层高度约为1 200m,远远高于珠峰地区的观测结果,但低于敦煌地区的边界层高度。

英文摘要：

In order to meet the third Tibetan Plateau Experiment of Atmospheric Sciences,the Urumqi Institute of Desert Meteorology of China Meteorological Administration carried out an atmospheric scientific experiment on the detection of troposphere and low stratosphere using a radiosonde at Minfeng station on the north side the Qinghai-Xizang Plateau in July 2011.By analyzing the intensive radiosonde data obtained at Minfeng sounding station from 1 to 31 July 2011,the results show that：（1） Because of the thermal influence of plateau terrain,the height of troposphere may reach more than 16 000 m in summer at Minfeng station,its absolute height is approximately same with the absolute height of troposphere at Everest region.（2） Summer subtropical westerly jet on the north side of the Qinghai-Xizang Plateau behaves strongly,showing the east-west direction distribution,and thickness is about 12 000 m.With the maximum wind speed center located in 10 700 to 11 400 m heights,the maximum wind speed can reach 45 m·s-1.（3） Affected by the subtropical westerly jet in the bottom of the west and southwest winds,the water vapor over the northwest of the Qinghai-Xizang Plateau will be transported to the south of Tarim basin in summer.There have a high relative humidity value layer from 3 000 to 7 500 m heights at Ruoqiang,Minfeng and Hetian stations.The average relative humidity is about 60% to 70%,maximum humidity 85%,below the height of 3 000 m and a height of 8 000 m above the atmosphere with low humidity.（4） The convective boundary layer in daytime can be up to 3 200 m heights and the stable boundary layer in nighttime is about 1 200 heights,which is far higher than the observations of the Mount Everest region,but lower than the boundary layer height in Dunhuang region.