加拿大林火天气指标系统在通化市的应用

针对通化市林火特点,引入加拿大林火天气指标系统,利用通化市1996—2010年气象资料和森林火灾数据,研究林火天气指标与林火的相关性,并划分森林火险等级.结果表明:除了干旱码(DC)外,林火次数与其他林火天气指标极显著相关;受害森林面积、火场总面积与林火天气指数(FWI)、初始蔓延指标(ISI)极显著相关,与细小可燃物湿度码(FFMC)虽然没有达到极显著相关,但显著度与0.01水平很接近,因此可以证明加拿大林火天气指标系统适合通化市进行林火天气预报.按照极端火险天气小于3%的原则和几何方法划分了森林火险级别.4级火险天气下林火频率、火场面积比例、受害森林面积比例最大,森林火灾发生近似于正态分布,因此此种等级划分方法比较适合通化市,但需要更多的森林火灾资料加以验证.

Applying Canadian Forest Fire Weather Index System in Tonghua City

According to the characteristics of forest fires in Tonghua City,we introduced the Canadian forest fire weather index system.We studied the correlation of fire weather indexes and forest fire,and division of forest fire danger rating with the forest fire data and the meteorological data of 1996—2010 in Tonghua City.The results indicate that number of forest fires and other forest fire weather indexes are highly significant in addition to Drought Code;forest area burnt, area burnt and Fire Weather Index, Initial Spread Index are also highly significant;forest area burnt, area burnt and Fine Fuel Moisture Code aren't highly significant, but the significances are very close to 0.01,so Canadian forest fire weather index system is suitable for Tonghua City.We divided forest fire danger ratings on the premise that extreme days should be less than 3% of the total study period and the geometric method.Forest fire frequency,area burnt ratio and forest area burnt ratio are the largest under level 4 of fire weather.Forest fire is similar to normal distribution,so the hierarchy method is suitable for Tonghua City,but further examination and comparison are required to make the system for forest fire forecast in Tonghua City.