额济纳绿洲夏末典型晴天小气候特征分析

绿洲系统特有的地理地貌形成了绿洲特殊的小气候特征。利用额济纳绿洲2003年9月8～10日小气候观测资料，分析了绿洲柽柳林的小气候特征。在柽柳林内，地表和近地层大气温度有明显的日变化，日间地表给大气加热，大气温度呈超绝热递减率随高度递减；夜间大气给地表加热，大气为稳定层结。近地层空气湿度的日变化与温度相反。林内空气温度的垂直分布主要取决于冠层与地表吸收太阳辐射状况。在林冠顶层，白天以上升气流为主，夜间以下沉气流为主，绿洲荒漠环流效应已经不明显。绿洲上空大气浑浊度小，对太阳辐射的削减较少，绿洲具有很好的光资源背景。

Analysis on Microclimate Characteristic of Typical Clear Day in Ejina Oasis in Late Summer

The geographical characteristic of the oasis system has formed the special microclimate characteristic in oasis. Utilizing the observation data of Ejina oasis on 8-10 September 2003, the microclimatecharacteristic of oasis Tarnaris Spp has been analyzed. In the Tarnaris Spp, the ground surface temperature and surface layer temperatures have obvious daily change. At daytime, ground surface heats up the atmosphere and the atmospheric temperatures decreases with height in superadiabatic state; at night, the atmosphere heats up the ground surface, and the atmosphere is steady stratification layer. The daily change of air humidity in surface layer is contrary to that of temperature. The vertical distribution of air temperature in Tarnaris Spp depends on mainly the absorbing solar radiation of ground surface and canopy layer. In canopy, it is mainly updraft at day time and downdraf at night. The desert circulation effect is not obvious. The atmospheric turbidity in oasis is small; the solar radiation is decreased less. So the oasis has good light resource background.