【摘要】 本文分析了1987年5月大兴安岭特大森林火灾的气象成因。前期干旱、少雨及5月上旬气温的显著偏高;是发生特大火灾的气候背景。大兴安岭位于我国最北部,属于寒温带,年平均气温只有-3—-6℃,有机物分解缓慢,使林内可燃物越积越多,是发生火灾的物质基础。在已有大量火源存在的情况下,正逢有强干冷锋过境,平均风速达8—12m/s,最大17.0m/s,使火势急速蔓延,是造成特大森林火灾的最关键因素。地形与气温、积雪有密切关系,也对火场的蔓延有一定的影响。更多还原

【Abstract】 In this paper,the meteorological factors of the catastrophic forest fire in Da Hinggan Lingregion of northeastern China in May,1987 have been analysed.It is found that the drought andless rainful in the previous period,and much higher temperature in the first ten-day of May arethe climatic conditions of the forest fire.Da Hinggan Ling region is located in northeastern China,which is part of the frigid-tempe-rate zone and the annual mean temperature is—3 to—6℃.Therefore,the organic matters aredecomposed rather slowly and make more and more combustibles accumulated in the forest.Itprovides the material condition of the fire.A very strong dry cold front with the average wind speed 8—12m/s,and the extreme speed17.0m/s,just passed away when a large number of fire points were in existence,which spreadedthe fire over wide areas rapidly.This is the key factor of the fire.In addition,the topographicfactor which related to the temperature and the snow cover also affected the extension of thefire.更多还原