Abstract:

Based on the meteorological data of dustweather, the dailymean temperature and p recip itation inMinqin in sp ring from 1976 to 2005, the temporal and spatial characteristics of dustweather and relations between dustweather and weather conditions, water resources as well as human activitieswere analyzed. The results show thatmost of the dustweather occurred from noon to evening and lasted for 1 to 2 hours, and it p resented decreasing trend. Dust weather has negative correlation with p recip itation in Minqin area in sp ring. Itwas also revealed that the special geographical location, the significant reduction of Shiyang River runoff and population growth and so on resulted in more dustweather in sp ring.

Key words: Minqin area, sp ring, dustweather, cause

摘要：

用民勤气象站1976～2005年春季沙尘天气的观测资料,分析了沙尘天气的时空变化特征与气象条件、水资源以及人类活动的关系。结果表明:春季民勤地区的沙尘天气大多发生在中午至傍晚,持续时间一般在1～2 h。沙尘天气总的发展趋势在减少,它与降水量之间有很好的反相关性;民勤地区特殊的地理位置所形成的气候背景、石羊河流域来水的大幅度减少、水资源不合理的开采与利用、人口增长对生态环境的压力等方面的影响都造成该地春季沙尘天气较多。

　

关键词: 民勤地区, 春季, 沙尘天气, 成因