甘肃民勤地区沙尘暴变化趋势及影响因素

Changing Trend of Sandstorm and Its Influencing Factor in Recent 57 Years in Minqin of Gansu Province

利用民勤国家基准气候站1954～2010年气象观测资料,运用线性拟合、Mann-kendall和相关性检验等方法分析了民勤地区近57 a来沙尘暴变化趋势及影响因素,结果表明:民勤沙尘暴的出现时间和频次有明显的日变化,沙尘暴有月际、季节差异,年际和年代际变化趋势明显,年际变化出现突变,1992年为突变点;沙尘暴强度和所造成的危害有增大的趋势。影响民勤沙尘暴的因素主要是大风次数、风力、气温和自然环境,降水增加相对湿度增大在一定程度上抑制沙尘暴的出现,人为因素和局部环境对沙尘暴的发生、发展有一定的影响。

Based on meteorological observation data from Minqin national reference climate station during 1954 -2010, the changing trend and its influencing factor of sandstorm were analyzed by using linear regression and Mann - kendall test in recent 57 years in Min- qin. The results show that sandstorm frequency and occurrence time had obvious daily variation, and there were monthly and seasonal difference. The annual and decadal variation of sandstorm days presented obvious change tendency, and appeared abrupt change in 1992. The intensity and harm of sandstorm presented increasing trend. The main factors affecting dust storm were gale days, wind speed, temperature and the natural environment in Minqin. Increase of precipitation and relative humidity would bate sandstorm occur- rence in some extent. Human factors and local environment had a certain impact on dust storm occurrence and development.