关键词: 沙尘天气, 年(际)变化, 季节变化, 空间分布, 青海

Abstract: The interannual,decadal and seasonal temporal changes of dust weather were analyzed with the regression method and Mann-Kendall test based on the daily dust weather data observed by 50 meteorological stations over Qinghai Province of China during the period from 1961 to 2015,and the spatial variations of dust weather at different levles were researched using the Inverse Distance Weighting interpolation.The results are as follows: ① The dust weather days were in a decrease trend in a fluctuation way during the period from 1961 to 2015,and the annual mean dust weather days increased by 3.42 d·a^-1 (P<0.01).The decrease speed of floating dust days was the highest,and that of dust storm days was the lowest.During the 55 years,the days of three kinds of dust events increased at first,and then decreased.The days of dust weather began to decrease from 1976.The abrupt change of dust weather days occurred in 1994,and dust weather occurred froquently in the 1970s with population growth and land use intensification; ② Curve of the seasonal variation of dust weather days was “V-shaped” from spring to winter,that was to say,the most dust weather days appeared in spring and winter,and then in summer and autumn.The decrease trend of the days of dust storm,blowing dust and floating dust were significantly high from November to next July (α=0.01),and slightly high from October to September (α=0.01); ③ Dust storm and float dust generally occurred most frequently in the Qaidam Basin.The center of frequent occurrence of blowing dust was in Wudaoliang south of the Kunlun Mountains,and the dust weather was dominated by blowing dust in Qinghai.

Key words: dust weather, interannual variation, seasonal variation, spatial distribution, Qinghai