山地冰川因具有高反照率、冰川风、逆温层及高值降水等特征而形成了独有的局地微气候，尤其是作为高值降水中心，对径流变化具有重要影响。本文基于祁连山中段北坡摆浪河21号冰川末端（海拔4 350 m）2020年9月2日—2021年8月28日的气象观测资料，开展了微气象特征分析，与临近不同海拔、下垫面的同期降水以及祁连山典型冰川区降水进行了比较，并对最大降水事件过程开展环流成因分析。研究发现：摆浪河21号冰川区气温超过0 ℃的天数有84 d，集中在5—9月；冰川风盛行，不同于其他冰川区的山谷风循环；天气主要以多云为主；入射与反射短波辐射月最大值分别出现在5月和4月。摆浪河21号冰川降水主要集中在4—8月，降水频次和强度均随着云量的增加而增加。观测年最大降水事件（2021年7月25—27日）属于局地对流降水，中高纬西北-东南向水汽输送为降水区提供了大量水汽；低层辐合和高层辐散、层结不稳定造成了强烈的暖空气上升，加之降水区位于槽后脊前不断有冷空气输入，冷暖交汇促使降水发生。

Alpine glacier areas have unique glacial microclimates due to the characteristics of high albedo， glacier wind， inversion layer and high-value precipitation， especially high-value precipitation is an important factor influencing the change of runoff. Based on the in-situ meteorological observations on the Bailanghe Glacier No. 21 from 2nd September 2020 to 28th August 2021， the micrometeorological characteristic analysis was carried out， and the similarities and differences were compared with the simultaneous precipitation observations at different elevations and underlying surfaces in the vicinity and the precipitation observations in typical glacier areas of Qilian Mountains. Furthermore， the circulation mechanism of different types of precipitation events was analyzed. The study shows that the number of days that the daily mean temperature exceeded 0 ℃ is 84 days， only occurring from May to September. Bailanghe Glacier No. 21 is dominated by glacier wind all year round， unlike the valley wind cycle in other glacier areas； the weather is mainly cloudy； the monthly maxima of incident and reflected shortwave radiation are in May and April， respectively. Precipitation in this region is mainly concentrated in April-August， and both the frequency and intensity of precipitation increase with the increase of cloudiness. A typical precipitation process （July 25-27， 2021） was selected to analyze the circulation drive. It was found that this precipitation process belongs to local convective precipitation in mountainous areas. The northwest-southeast-oriented water vapor transport belt from high latitude to mid-latitude provides water vapor. Moreover， low-level convergence and high-level dispersion， stratification instability and strong upward motion induce the warm air rising and the precipitation area is located in front of the ridge behind the trough with constant cold air input， and then the cold and warm convergence prompt precipitation to occur.