基于灾情数据的新疆雪灾的评估与区划

Study on snow disaster assessment method and snow disaster regionalization in Xinjiang

选取1955-2017年新疆因雪灾造成的牲畜受灾数量、作物受灾面积、经济损失三大灾情数据,揭示新疆雪灾时间和空间分布特征,通过构建雪灾灾损指数,对新疆雪灾进行区划。分析表明:新疆雪灾的发生北疆多于南疆,山区多于盆地,西部多于东部,主要集中发生在阿尔泰山区、天山山区及昆仑山区,灾情最重的是阿勒泰地区、伊犁地区、塔城地区;进入2000年以后,雪灾呈现明显高位震荡特点;利用多指标综合评估法,运用连续型随机变量分布密度近似求法,求得的新疆雪灾灾损指数,能客观反映新疆雪灾灾情;雪灾灾损指数遵从Γ分布,根据Γ分布函数属性及各类雪灾事件发生概率,进行了新疆雪灾等级区划。研究成果可为决策服务及气候可行性论证提供理论依据,对科学准确地制定防灾备灾措施、及时组织开展雪灾应急救助工作以及灾后的恢复重建决策给予一定参考。

In this study, the disaster data by the snowstorm(e.g. number of livestock affected, crops affected area and economic losses) were used to reveal the temporal and spatial distribution characteristics of snow disasters in Xinjiang Uygur Autonomous Region from 1955 to 2017. Firstly, the snow disaster index in Xinjiang was constructed by using the multi-index comprehensive evaluation method. Then, the approximate algorithm for acquiring the distribution density of continuous random variables was used to calculate the distribution function of the snow disaster index. Finally, according to the characteristics of the distribution function and the probability level distribution of natural disaster risk events, the zoning of snow disaster level in Xinjiang was conducted. The results show that:(1) the occurrence of snow disasters in northern Xinjiang is more than that in southern Xinjiang, in mountain regions are more than in basin regions and in the west is more than in the east of Xinjiang. Furthermore, this mainly occurs in the Altai Mountains, Tianshan Mountains and Kunlun Mountains. The worst disasters are located in Aletai, Yili and Tacheng Prefectures. Particularly, after 2000, the snow disaster has showed obvious high-level shock characteristics;(2) the snow disaster index constructed by the multi-index comprehensive evaluation method can objectively judge the magnitude of the snow disaster.(3) the snow disaster in Xinjiang follows the gamma distribution, and the zoning based on this theory shows that the high-incidence areas and heavy disaster areas take place in Altay, Tacheng and Yili, the frequent areas in the south foot of the Tianshan Mountains and the Kunlun Mountains, and the snow disaster occurs less in Eastern Xinjiang. The above research provides a theoretical basis for decision-making services and climate feasibility demonstration, meanwhile, which is helpful for scientifically and accurately formulating disaster prevention and preparedness measures, timely organizing snow disaster emergency rescue work, and recovering the post-disaster reconstruction.