新疆区域近50a积雪变化特征分析

利用新疆91个气象台站1960-2011年的观测资料, 对南北疆及天山山区冬春年(10月-翌年5月)的积雪日数、最大积雪深度、积雪初始、终止日期等因子进行了统计分析, 并通过Kringing插值计算了新疆区域平均最大积雪深度的空间分布.结果表明: 新疆冬春季积雪主要分布在天山以北, 厚度可达30 cm以上, 天山以南积雪比较浅薄, 大部分在10 cm以下;50 a来, 南北疆及天山山区的积雪深度均呈小幅增长(天山山区增幅最大), 积雪日数呈略微降低趋势, 积雪初始、终止日期无明显变化. 天山山区的积雪变化与北疆有较高的相关性, 它们积雪深度和积雪日数的相关系数分别达0.708和0.614, 南疆积雪变化与它们几乎没有相关性;积雪深度与冬春年降水量的变化均有很好的一致性, 尤其在北疆,二者相关系数高达0.702, 但与平均温度呈低的负相关;积雪日数与冬春年降水量变化没有明显相关关系, 但均与气温呈较好的负相关, 在北疆二者的相关系数达-0.742.

Analysis of the Variation Characteristics of Snow Covers in Xinjiang Region During Recent 50 Years

Based on the meteorological data from 91 stations in Xinjiang from 1960 to 2011, the number of days with snow cover, the maximum snow depth, and snow beginning date and ending date are analyzed. The spatial distribution of maximum snow depth is calculated by the Kringing interpolation. The results show that snow is mainly distributed in the north of the Tianshan Mountains. Its depth can reach more than 30 cm. Snow depth in the south of the Tianshan Mountains is relatively small, mostly less than 10 cm in winter and spring. Snow depths in North Xinjiang, South Xinjiang and the Tianshan Mountains have increased slightly in recent 50 years (especially in the Tianshan Mountains). However, the number of days with snow cover has decreased slightly, and the snow beginning date and ending date have changed insignificantly. It is found that the correlation of snow cover change is significant between the Tianshan Mountains and North Xinjiang, with a correlation coefficient of 0.708 for snow depth and that of 0.614 for number of days with snow cover. It seems no significant correlation of snow cover change between South Xinjiang and the others. Snow depth is positively correlative to precipitation, with a correlation coefficient of 0.702 in North Xinjiang. There is a good negative correlation between the number of days with snow cover and air temperature, with a correlation coefficient of 0.742 in North Xinjiang, but there is no obvious correlation between the number of days with snow cover and precipitation in winter and spring.