摘要
利用2005年中国科学院珠穆朗玛峰地区科学考察期间的无线电高空探测资料和超声风温仪观测资料,分析了珠穆朗玛峰地区边界层高度、风速、风向和比湿的日变化以及两个海拔高度不同的观测站（珠峰站和曲宗站）的近地层能量交换特征,得到珠穆朗玛峰地区5月份边界层高度日变化比较明显,因冰川风的存在影响了大气边界层,边界层高度最高为3888 m;白天珠穆朗玛峰地区低层都存在逆湿现象.因珠峰站和曲宗站海拔高度、下垫面状况不同,能量交换特征也不同：4～5月份白天珠峰站感热大于潜热,而曲宗站潜热大于感热;珠峰站土壤热通量转为正、负值的时间早于曲宗站.
The Mt. Qomolangma （Everest）, the highest peak of the Plateau, is a representative region of mountains of Himalayas. During the Scientific Expedition to Mt. Qomolangma （Mt. Everest） of Chinese Academy of Sciences in spring of 2005, one radio sonde system and one turbulent measurement system [sonic anemo-thermometer （CSAT3）] were set up in the base camp of Mt. Qomolangma（28. 137°N, 86. 854°E, and 5149 m above m. s. l. ）. Another turbulent system [sonic anemo-thermometer （CSAT3）] was set up at Quzong Station （28. 310°N, 86. 896°E, and 4475 m above m. s. l. ）. The turbulent flux measurement was set up at 3 m above the ground at both the Stations. The density of water vapor and concentration of carbon dioxide was obtained by an LI-7500 device at the two stations. The field turbulence data, after removing noise and bad records caused by instrument failures, are given every 30 minutes.
With the observational radio sonde and turbulent measurement data, the structure of atmospheric boundary layer and the characteristics of energy exchange in the near surface were analyzed over Mt. Qomolangma region. The results showed that： （1） The diurnal variation of boundary layer height is obvious, the structure of boundary layer is affected by glacier wind, and its highest is 3888 m which is observed at 14：00 on 21 May when it blows downward north wind. When blowing downward south wind at low layer, the height is less than 600 m. In daytime there is moisture inversion at low layer over Mt. Qomolangma region. （2） The characteristics of energy exchange in the near surface is different with vary altitude and underlying surface at Qomolangma and Quzong Stations. In daytime the sensible heat flux dominates at Qomolangma site, but the latent heat flux is larger than the sensible heat flux at Quzong station. The change time from positive to negative value of soil heat flux at Qomolangma site is earlier than of at Quzong station. （3） Downward shortwave radiation at Quzong station is smaller than those at Qomolangma station, but upward long wave radiation at Quzong station is significant larger than those at Qomolangma station. Upward shortwave radiation at Qomolangma station is larger resulting from high albedo. Such variation is due to sunrise at Qomolangma station earlier than it at Quzong site, underlay situation is different between two sites, the altitude at Qomolangma site is higher than it at Quzong site, and surface temperature at Quzong site is higher than it Qomolangma site. （4） Because of glacier wind prevailing, the structure of boundary layer becomes more complex in this region.
出处
《高原气象》
CSCD
北大核心
2006年第5期807-813,共7页
Plateau Meteorology
基金
中国科学院知识创新工程重要方向项目(KZCX3-SW-231
KZCX3-SW-339)
国家自然科学基金项目(40520140126)
科技部社会公益研究专项"珠穆朗玛峰地区对全球变化的响应"(2005DIA3J106)共同资助
关键词
边界层结构
涡旋相关法
近地层能量交换
珠穆朗玛峰地区
Structure of the atmospheric boundary layer
Eddy correlation method
The energy exchange in the near surface layer
Mount Qomolangma region
