鄂尔多斯高原西南部清代霜雪灾害研究

通过对鄂尔多斯高原西南部清代文献资料的搜集、整理和定量分析，研究了该区霜雪灾害等级、阶段、时空变化、周期及其成因。结果表明，鄂尔多斯高原西南部共发生霜雪灾害57次，其中轻度10次，中度43次，重度4次。灾害变化可分为1644-1733年、1734-1783年、1784-1833年、1834-1863年及1864-1912年等5个阶段。时间上，灾害主要发生在秋末冬初和初春；空间上，灾害主要分布在银川、中卫、平罗、永宁、盐池和定边，共6个地区。同时，小波分析结果表明，灾害存在着4个明显的发生周期，即3 a、6 a、27 a和58 a的周期。降雪或寒流引起的气温骤降至0℃以下是造成鄂尔多斯高原西南部霜雪灾害发生的主要原因。

Study of the frost and snow disasters in southwestern Ordos Plateau during Qing dynasty

Based on collection, arrangement and mathematical analysis of historical documents and materials, the grades, stages, spatiotemporal difference, period and cause of frost and snow disasters from 1644 through 1912 (i.e., Qing dynasty) in southwestern Ordos Plateau are researched. During this period 57 disaster events had occurred, of which there were 10 of mild grade, 43 of moderate grade and 4 of severe grade. Disaster period can be divided into five phases:1644-1733, 1734-1783, 1784-1833, 1834-1863 and 1864-1912, respectively. Temporally, frost and snow disasters in the region frequently occurred in November, December, April and March. Spatially, the disasters concentrated in Yinchuan, Zhongwei, Pingluo, Yongning, Yanchi and Dingbian. Wavelet analysis showed that the occurrence of frost and snow disaster events had four obvious periods (i.e., 3 years, 6 years, 27 years and 58 years). Sharp air temperature dropping to below 0℃ due to cold current was dominant inducement of frost and snow disasters in southwestern Ordos Plateau.