中文摘要：

应用1995～2009年冬季（11月至翌年1月）共45个月,内蒙古地区118个地面观测站沙尘暴、能见度、气温、相对湿度、风速、降雪量、积雪深度和常规格点场资料,确定了不同范围的强和特强沙尘暴标准,分析了环流形势和气象要素。结果表明：近15年内蒙古地区冬季发生强和特强沙尘暴共9次,其中强沙尘暴6次、特强沙尘暴3次,均是局地性;在强或特强沙尘暴发生的前期或当年均有不同程度的旱情发生;500hpa平均高度场环流为两槽一脊型,海平面平均气压场为南高北低型,冷空气的路径多为西北路或北路;强和特强沙尘暴发生期间,旬和月的气温、相对湿度、风速均有不同程度的变化,而强和特强沙尘暴出现前1至2天,最高气温、最低气温、相对湿度的值可达到最大,风度值为最小,当强和特强沙尘暴出现当日,最高气温达到最小,相对湿度达到最大,当强和特强沙尘暴过后,最低气温达到最小,相对湿度呈下降趋势。

英文摘要：

Based on the data including sandstorms,visibility,air temperature,relative humidity,wind speed,snowfall,snow depth and regular grid point data,which coming from 118 ground stations in Inner Mongolia,during the 45 months,from 1995 to 2009（from November to the following year′January） in winter,the standards of heavy and extra-heavy sandstorms belonging to different areas are determined,and convection situation and meteorological elements were analyzed.The results of the research were as follows： There are 9 heavy and extra-heavy sandstorms in Inner Mongolia in winter during the past 15 years,including 6 heavy sandstorm and 3 extra-heavy sandstorms,both of them fall into local phenomenon;Drought had occurred in varying degrees in the early stage or that year before heavy and extra-heavy sandstorms broke out;Circulation situation manifested itself as ＂the two troughs and one ridge＂ in 500hpa average height field,and the situation of ＂high in south and low in north ＂ was existed in the average sea level pressure field,and the path of cold air generally presented the northwest path or north path.During the period of the heavy and extra-heavy sandstorms,there were different extent variations existing in every ten days and monthly which embodied not only in temperature but also in relative humidity and wind speed;Before the onset of the heavy and extra-heavy sandstorms,about 1 to 2 days,the highest temperature,lowest temperature,and relative humidity climbed to the peak,however,the wind velocity slided into the bottom;At the time of the heavy and extra-heavy sandstorms occured,the highest temperature reached its lowest point and the relative humidity reached its highest point;When the heavy and extra-heavy sandstorms passed through,the lowest temperature reached the minimum and the relative humidity declined.