1971—2015年鄂尔多斯市大雾天气特征分析

The characteristics analysis of heavy fog of Ordos from 1971 to 2015

利用1971—2015年内蒙古鄂尔多斯市11个国家区域自动站能见度≤1km大雾天气地面观测资料，进行分类整理，对大雾时空分布、日变化、持续时间等气候特征及气象要素的特点，进行分析判断，结果表明：鄂尔多斯市大雾西北部最少，东南部最多，有很大的波动性和明显的季节性。21世纪70年代呈下降趋势，80年代呈上升趋势，近2ａ出现猛增趋势。出现大雾高峰期07—10时，持续时间主要在0～4h。适宜的气温、微弱的风力、潮湿的空气和一定厚度的逆温层，有利于形成大雾天气。

According to the observation data of foggy visibility which is no more than1km of11national regional automatic meteorological stations in Ordos from1971-2015,temporal-space distribution、daily variation and the duration of heavy fog were analyzed.The results show that the heavy fog of southeast is more than northwest in Ordos,and it is volatility and seasonality.The dates of foggy is down trend in the70s and rising trend in the80s of21century,moreover,it grows rapidly in recent two years.The heavy fog usually appears at7am to10am and lasts0to4hours.The heavy fog can be resulted by suitable temperature、breeze、moist air and inversion layer.