杭州单体钢架大棚风灾时空特征

基于杭州国家基准气候站1951—2018年大风逐日资料和经过质控后的373个自动气象站2014—2018年小时极大风速资料,采用MK方法和平均值法,分析杭州建站以来的大风年际变化规律和近5年不同风力等级风的空间分布特征,结合单体钢架大棚风灾等级指标和设施大棚第3次农业普查的乡镇级数据,提出农业发展建议。研究结果表明:造成单体钢架大棚重度受损的大风天数年际变化为波动中下降,2001年出现突变,下降趋势显著,各季变化类似;造成单体钢架大棚轻、中、重3个等级的各级风发生天数和时次数的多发地均为临安西北部山区、富阳安顶山和杭州湾等区域,其中杭州湾区域也是杭州设施农业主要发展地,需进行重点防御,适当提高建设标准;杭州中心区域为大风低值区,可进一步发展设施农业。一年四季中,造成单体钢架大棚中到重度风灾的风出现天数和时次数均为夏季最高、春季其次、秋季最少,持续时间以冬季最长、秋季次之、春季最短。

Temporal and Spatial Characteristics of Wind Disasters for Single Steel-Frame Greenhouses in Hangzhou

Based on the gale data of Hangzhou National Base Station from 1951 to 2018 and the maximum wind speed data of 373 automatic meteorological stations after the quality control from 2014 to 2018, to provide suggestions on agricultural development, the MK method and GIS mapping technology are used to analyze the inter annual variation of strong winds since the establishment of Hangzhou Station and the spatial distribution characteristics of different wind levels in recent five years, combined with the wind disaster grade index of single steel frame greenhouses and the town level data of the third agricultural census. The results show that the number of strong wind days in the year of severe disasters in the greenhouses decreases fluctuationally, and a sudden change happened in 2001, with a more obvious downward trend, and the changes in various seasons are similar. As a result, the areas where the greenhouses suffered from the light, medium and heavy wind disasters are in the northwestern Linan, Anding Mountain of Fuyang and the Hangzhou Bay in the northeastern Zhejiang Province. The Hangzhou Bay area is also the main development area of facility agriculture, which requires higher construction standards. The central area of Hangzhou is the low value area of high wind, which is conducive to the further development of facility agriculture. The number of days and times of serve wind disasters causing moderate to severe wind disasters in single steel frame greenhouses are the highest in summer, followed by spring, and the least in autumn, with the longest duration in winter, followed by autumn and the shortest in spring.