Based on the hail observation data at weather stations from 1 961 -201 0 in Shaanxi province,tem-poral and spatial distribution characteristics of Hail in 38 apple fruit industry base countries is obtained.According to disaster risk forming mechanism,the assessment model of hail disaster for apple is constructed by using meteoro-logical data,basic geographic information data,socio-economic statistic data,and history disaster situation data and so on,according to the factors,such as the risk of disaster causing,the vulnerability of disaster body,and the ability of disaster prevention/reduction.The results are shown as follows.(1 )Hail in apple fruit area has the char-acteristics of more in North,mountain,and plateau area than in north,plain,and basin area;more in Yan’an and western Weibei fruit area than in eastern Weibei and western Guanzhong fruit area.There are fluctuations of hail occurrence in the 1 970 s and 1 980 s,and has been decreased from the 1 990 s.Hails occurred mostly in summer, and spring and autumn took second place.The diurnal variation of hail is single peak type,and the peak period of hail occurrence is from 1 4∶00 to 1 9∶00,with the frequency of 78.7%.(2)The severe risk regions mainly distrib-ute in the midwest of Yan’an,and the annual hail day is 2 d.The moderate risk regions mainly distribute in most areas of Hancheng,Heyang,Chengcheng,Pucheng,northern Fuping,Yaozhou,Chunhua,Binxian,Changwu, and northern part of these areas of non-severe risk regions;and the annual hail day is 1 ~2 d.The mild risk re-gions mainly distribute in the part of the northwest and eastern of Guanzhong,and the annual hail day is less than 1 d.%选取陕西省1961－2010年气象观测站冰雹观测数据，分析38个苹果基地县冰雹的时空分布特征，结合基础地理信息数据、社会经济统计数据和历史灾情等方面资料，基于自然灾害风险形成原理，从致灾因子危险性、承灾体易损性以及防灾减灾能力3个方面，构建陕西苹果冰雹灾害风险评估模型，利用GIS技术完成陕西苹果果区冰雹灾害风险区划。结果表明：①陕西苹果果区冰雹北多南少，高原和高山多于平川、盆地；延安、渭北西部果区多于渭北东部、关中西部果区；1970－1980年代是冰雹高发期且波动较大，1990年以后有所减少；降雹随季节变化明显，夏季冰雹日数最多，春秋次之；冰雹日变化呈单峰型，14∶00－19∶00是陕西苹果果区降雹的高峰时段，出现频次为78.7％。②陕西苹果果区冰雹灾害重度风险区主要分布在延安中西部，该区年平均雹日约2d；中度风险区主要包括韩城、合阳、澄城、蒲城、富平北部、耀州区、淳化、彬县、长武大部及其北部所有非重度风险区，该区年平均雹日1～2d；轻度风险区主要分布在关中西北部及东部部分地区，该区年平均雹日不足1 d。
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