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利用石羊河流域上游、中游、下游当地气象站1961~2007年的冬季气温、降水、蒸发、最大冻土深度和1962~2008年沙尘天气的常规观测资料,分析了近47 a石羊河流域冬季最大冻土深度和春夏沙尘日数的空间分布以及时间变化特征,近而采用相关系数法分析了冬季各气象因子与冬季最大冻土深度和次年春夏沙尘天气之间的相关关系,以进一步探讨石羊河流域冬季最大冻土深度与次年春夏沙尘天气的关系,结果表明:空间分布上,受地理位置和海拔高度等因素影响,石羊河流域冬季最大冻土深度分布呈东南—西北走向,而沙尘日数分布呈西北—东南走向,北部荒漠低海拔地区的冻土深度小于南部山区高海拔地区,而低海拔地区的沙尘日数明显高于高海拔地区。时间分布上,石羊河流域以及流域上、中游冬季最大冻土深度和沙尘日数线性趋势一致,皆随时间递减,在下游冬季最大冻土深度和沙尘日数线性趋势相反。相关系数法分析表明,石羊河流域冬季冻土深度与次年春夏沙尘天气发生日数之间都存在正相关,究其原因可能归根于冬季热力因子和水分因子对冬季最大冻土深度和次年春夏沙尘发生日数影响的一致性,其中热力因子的作用大于水分因子。
Based on the observation data of winter temperatures, precipitation, evaporation, maximum frozen soil depth and dusty weather from 1962 to 2008 in the upper, middle reaches and downstream of the Shiyang River basin from 1961 to 2007, The spatial distribution of the maximum frozen soil depth and the number of spring-summer dust days in the basin are also analyzed. Correlation coefficients are used to analyze the relationship between the meteorological factors in winter and the maximum frozen soil depth in winter and the dust weather in the following spring and summer The relationship between the maximum frozen soil depth in winter in Shiyang River Basin and the dust and sand weather in the following year was also discussed. The results show that the spatial distribution of winter maximum frozen soil in Shiyanghe River Basin is affected by the geographical location and altitude, The distribution of depth of dust shows the trend of southeast to northwest while the distribution of dust days shows northwest and southeast. The depth of permafrost in low altitude of north desert is less than that of southern mountain, while the number of dust days in low altitude is obviously higher than that of high altitude. On the time distribution, the linear trend of the maximum frozen soil depth and the number of dust days in the upper and middle reaches of the Shiyang River Basin and the middle reaches of the river basin all coincide with each other, all decreasing with time. The linear trend of the maximum frozen soil depth and the number of dust days in the lower reaches of winter is opposite. Correlation coefficient analysis shows that there is a positive correlation between the winter frozen soil depth in Shiyanghe River Basin and the number of dusty weather in the next spring and summer. The reason may be attributed to the influence of winter heat and water factors on winter maximum frozen soil depth and The following year the impact of spring and summer sandstorm consistency, of which the role of thermal factors greater than the water factor.