近44a毛乌素沙地西缘气候特征及其未来可能变化趋势

利用1971—2014年毛乌素沙地西缘气象观测资料,分析了该地区的气温、降水、相对湿度的时空变化特征,运用R/S分析法预测未来毛乌素沙地西缘气候要素可能变化趋势。结果表明:(1)近44 a毛乌素沙地西缘气温呈显著上升趋势,降水量呈弱的增加趋势,相对湿度呈弱的下降趋势,但是二者趋势并不显著。(2)近44 a毛乌素沙地西缘气温空间分布呈南高北低,降水和相对湿度均呈东多西少,各地气候倾向率存在明显的差异性,中部气温增幅较大,东部降水增加较多,南部相对湿度减少较多。(3)近44 a来毛乌素沙地西缘各气象要素变化均表现出一定的周期性,年平均气温主要存在4~5、8~10 a的振荡周期,降水量主要存在3~4、6~8 a振荡周期,相对湿度主要存在2~4、6~8 a的振荡周期。(4)毛乌素沙地西缘未来气温仍呈上升趋势可能性较大,未来降水量可能变为减少趋势,未来相对湿度变化不稳定。

The characteristics ofclimate changes in western edge of Mu UsSandy Land During the past 44 years and Estimation of future climatetrend

The temporal and spatial characteristics of temperature, precipitation and relative humidity in the western margin of Mu Us sandy land were analyzed by using the meteorological data from 1971 to 2014, and R / S method was used to predict the future climate change trend. The results showed that: 1) The temperature of the western margin of Mu Us sandy land increased significantly in the past 44 years and the rate of rise was 0.33°C/10a. Precipitation showed a weak upward trend and relative humidity showed a weak decreasing trend, but the two trend was not significant. In the future, the temperature of the western edge of Mu Us sandy land is likely to still rising, precipitation will become decreasing and relative humidity is not stable; 2) The spatial distribution of temperature in the west margin of Mu Us sandy land in the recent 44 years was in the south and north. Precipitation and relative humidity are in the east and west. There are obvious regional differences in climatic tendency of each climate element, the temperature increased greatly in the central region, and the precipitation increased more in the east than in the west, and the relative humidity in the south decreased faster than that in the north; 3) The temperature, precipitation and relative humidity of the western margin of Mu Us sandy land have obvious periodical oscillation in the recent 44 years. The average temperature is mainly 4-5a, 10-12 scales around the period of oscillation, precipitation exists 4-6a scale periodic oscillations and relative humidity is 4-6a scale periodic oscillations.