【摘要】 ＲＡＭＳ模式被应用于内蒙半干旱草原地区地气系统水热通量交换及水循环过程研究。本文通过敏感性试验，模拟了在半沙漠化和土壤水含量变化的情况下内蒙地区地气通量交换的变化及其对降水的影响。模拟结果表明，在半沙漠化条件下，地表感热通量大大增加，潜热减少，表面温度日振幅增大。对降水影响的分析证实，沙漠化对短期的由明显大尺度天气系统引发的降水影响与其长期的气候意义上的降水影响显著不同。对短期的天气系统引发的降水过程而言，沙漠化在一定程度上更加有利于不稳定能量的释放和降水机制的触发。从而使局地降水有一定程度的增加。土壤体积含水量对降水的响应也较为敏感。更多还原

【Abstract】 Regional Atmospheric Model System is used in the study of water and energy flux exchange in Inner Mongolia. Sensitive experiments show that under semi-desert condition, surface sensible heat flux increases while latent heat flux decreases. Diurnal amplitude of surface air temperatur becomes bigger. Analysis of precipitation proves that desertificatoin impact on precipitation is different for short term rainfan event caused by synoptic scale circulation and for long term total rainfall. To some extent, desertification is more favorable to initiate the release of unstable energy and makes precipitation easier to occur, thus cause increase of short-term precipitation.更多还原