利用乌鲁木齐市2011—2012年08时、20时L波段（1型）雷达探测的高空资料，分析了乌鲁木齐边界层内气温、风向、风速和相对湿度的垂直分布及其时间变化特征。结果表明：边界层内温度廓线的日变化和季节变化比较显著；各月均有逆温出现，且08时较20时更易出现逆温，20时只有冬季出现脱地逆温，冬季08时逆温层厚度较厚且强度最大。边界层内夏、冬两季风速随高度变化波动较大，春、秋两季变化较小。冬季在距地1000 m附近风速明显大于其它3个季节。地面层春、夏、秋三季08时盛行西南偏南风，冬季盛行偏东风和西南风；20时春季盛行东北风，夏秋盛行偏北风，冬季则盛行东风。随高度增加，大气环流对风的影响逐渐增强，至2500 m附近逐渐转换为西北风；日风向的变化具有明显的山谷风特点。08、20时的相对湿度冬季最大，夏季最小，且随高度增加，春、夏两季08、20时相对湿度的变化较大。%Based on the L-band radar system data during 2011-2012, we built the atmospheric boundary layer structure database in Urumqi. Atmospheric boundary layer conditions such as vertical distribution and time variation characteristics of temperature, wind velocity, wind direction and humidity were analyzed. The results show that there were significant changes in daily and seasonal variations in profiles of temperature in atmospheric boundary layer below 1 500 m, and they were basically stabile above 1 500 m. There was temperature inversion in each month which occurs more in the morning (8:00)than in the evening (20:00),and generally thicker and the strongest temperature inversion occured in winter. The wind velocity had more change with altitude increase in summer and winter, and less in spring and autumn. The wind velocity near 1 000 m altitude was significantly greater than that of the other 3 seasons. The prevailing wind direction in surface layer was SSW in spring, summer, and autumn, and E, SW in winter in the morning, as well as NE in spring, N in summer, E in winter in the evening. The wind direction had a significant characteristics of mountain valley breeze. There was the highest humidity in winter, and the lowest in summer, as well as a higher variation with altitude change in spring and summer.
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