潍坊冰雹时空分布特征和对农业的影响及对策

为了揭示潍坊地区冰雹的发生规律和分布特征，根据1971—2010年潍坊地区9个气象观测站的冰雹日观测资料，利用气候倾向率、M-K突变检验及EOF正交经验函数等统计方法，分析了潍坊地区冰雹的时空变化特征。结果表明：1971—2010年潍坊地区冰雹出现次数的气候倾向率为-0.55站次/10 a，呈减少趋势，且在2008年发生突变；冰雹一般出现在3—10月，呈明显的单峰型，5—7月出现次数最多，占冰雹出现总次数的77.74%；冰雹出现的日变化明显，以午后型为主，14—18时冰雹出现次数占52.26%。潍坊冰雹出现次数具有明显的地域分布特征，由西南向东北方向呈递减分布，临朐、安丘、诸城一带属多雹区，平原地区属少雹区，冰雹的发生受地形的影响，通过空间特征向量分析，冰雹出现次数具有空间一致性变化特性，它的分布呈西南—东北反向特征。由灾害调查知，潍坊冰雹灾害对农业的主要影响有粮食、黄烟、果树和设施农业等。加强冰雹预警预测，科学实施人工防雹作业是比较有效的防御手段。

Hail in Weifang: Temporal and Spatial Distribution and Its Influence on Agriculture

The paper aims to reveal the occurrence rule and distribution characteristics of Hail in Weifang. According to the hail daily data of 9 meteorological stations from 1971 to 2010, the authors analyed the characteristics of temporal and spatial distribution of hail in Weifang by using methods of linear tendency estimation, Mann-Kendall and EOF orthogonal empirical function etc. The results showed that: the hail climate tendency rate was -0.55 times/10 a in Weifang from 1971 to 2010, it showed a decreasing trend, a significant mutation occured in 2008; the hail generally appeared in the March to October, showing a single peak, most hail frequently from May to July, accounting for 77.74% of the total number of hail; the diurnal variation of hail was obvious, mainly in the afternoon type, the number of hail accounted for 52.26% from 14:00 to 18:00; the number of hail occurrence has obvious regional distribution characteristics, descending from southwest to northeast, hail-prone areas were concentrated in Linqu, Anqiu and Zhucheng, the plain area were relatively less; hail was affected by terrain, the number of hail occurrence had the characteristics of spatial coherence, and its distribution was reverse form the southwest to northeast, through the spatial feature vector analysis. According to the investigation, agricultural food, tobacco, fruit trees and agricultural facilities, etc,which were mainly affected by hail disaster in Weifang. Therefore, strengthening hail warning and forecasting and the implementation of artificial hail suppression are the effective means of defense hail disaster.