机构地区: 喀什师范学院物理系
出 处: 《西北师范大学学报(自然科学版)》 2013年第3期105-109,共5页
摘 要: 依据喀什地区喀什、巴楚和莎车3个气象站1991—2010年逐日地面观测资料,采用多元线性回归分析方法,探讨日平均温度、日平均气压、日平均相对湿度、日平均风速、气温日较差、气压日较差及地温日较差7个气象要素对喀什地区浮尘日数变化的影响.结果表明,在年序列上,浮尘日数变化主要影响要素是日相对湿度和日平均气温.日相对湿度越大,沙粒起动困难,浮尘天气越不易发生;日平均气温越大,下垫面越干燥,易形成浮尘天气.在季节序列上,春、夏、秋3季,下垫面增温剧烈,热力扰动加强,气温日较差和地温日较差对浮尘天气影响显著;春、夏、秋3季,降水较多,日相对湿度对浮尘天气发生有显著抑制作用;冬季,动力学条件影响加强,在各影响要素中气压日较差和平均风速占主要地位.由于喀什地区特殊的地理位置,日平均风速在春、夏、秋3季与浮尘日数呈负相关关系,较小风速有利于浮尘天气维持. According to the daily weather observation data in Kashgar area,including Kashi,Bachu and Shache from 1991 to 2010,the influence degree of seven meteorological factors including daily average temperature,daily average pressure,relative humidity,mean wind speed,daily range of temperature,daily range of pressure and daily range of ground temperature on floating dust weather are discussed.Multinomial linear regression analysis showed that the main meteorological factors affecting floating dust weather in Kashgar in annual series are the relative humidity and the daily mean temperature.Higher daily humidity and harder activity of the sand are less favorable for the dust weather.The higher of the daily temperature and the drier of the underlying surface,the more frequent of the dust weather.In spring,summer and autumn,the temperature of the underlying surface increases rapidly,the thermodynamic disturbance strengthens and the daily range of temperature,daily range of pressure and affected the floating dust weather markedly.In spring,summer and autumn,the rain is relatively heavy,so the daily humidity restrained the dust weather markedly.While in winter the dominant factors affecting the occurrence of floating dust weather are daily range of pressure and mean wind speed because of the dynamical condition strengthen.For the special geography of Kashgar,the mean wind speed has a negative correlation with the occurrence of floating dust weather from spring to autumn,and weaker wind is favorable for the persistent of the dust weather.