河西走廊东部冬季浅层地温与春季沙尘天气的关系

利用河西走廊东部民勤、凉州、永昌3个气象站1960~2010年冬季0、5、10、15、20 cm地温和1961~2011年春季沙尘暴和扬沙天气的常规观测资料,分析了河西走廊东部冬季浅层地温和春季沙尘天气日数的时空特征,进而探讨了春季沙尘天气与冬季浅层地温的关系。结果表明:受海拔高度、地理位置等影响,河西走廊东部冬季浅层地温有明显地域差异,其中高海拔的永昌最低,低海拔的民勤次之,而海拔介于民勤和永昌之间的凉州最高;春季沙尘天气日数自低海拔地区向高海拔地区逐渐减少,即民勤最多、凉州区次之、永昌最少;河西走廊东部的沙尘天气日数与浅层地温在空间上呈一定的负相关,二者的年变化趋势明显相反,即冬季浅层地温总体呈逐年升高的趋势,而春季沙尘日数呈逐年减少的趋势,且都存在6~7 a和9~10 a的周期;相关分析表明,河西走廊东部春季沙尘日数与冬季浅层地温呈负相关,其中与0 cm地温的相关性最显著。

Relationship Between Winter Shallow Soil Temperature and Spring Sand-dust Days in East of Hexi Corridor

Based on the shallow soil temperature at 0 cm,5 cm,10 cm,15 cm and 20 cm depths in winter during 1960-2010 and the sand-dust days in spring during 1961 -2011 from Minqin,Liangzhou and Yongchang meteorological stations in east of Hexi Corridor, the temporal and spatial distribution characteristics of winter shallow soil temperature and spring sand-dust days were analyzed,and their relationship was discussed.The results showed that the spatial distribution of soil temperature at different depths had obvious dis-tinction due to the altitude and geographic location influence.The winter shallow soil temperature in Yongchang with the highest alti-tude was the lowest,and that in Minqin with the lowest altitude was lower,while that in Liangzhou with altitude between Minqin and Yongchang was the highest.The spring sand-dust days decreased gradually from low altitude areas to high altitude areas,and it was the most in Minqin and the fewest in Yongchang.The annual changes of spring sand-dust days and winter shallow soil temperature were obviously contrary,and there were an increasing trend of winter soil temperature and decreasing trend of spring sand-dust days. The vibration periods of them were 6-7 years and 9-10 years.The sand-dust days had significant negative relation with soil temper-ature at different depths,especially for 0 cm soil temperature,the correlation was the most significant.