以1961-2010年间东北地区逐日气象观测数据为基础,计算春季逐日森林火险气象指数(FFDI)并用广义帕累托分布(GPD)模型对FFDI极值进行了拟合,结果表明:东北地区春季FFDI高值区分布于吉林西部、辽宁西部和内蒙东四盟市南部区域,高值区基本位于山脉背风坡一侧.春季各站FFDI值的趋势变化大致以大兴安岭山脊为界,山脊以东站点的FFDI趋势系数大部分为负值,其中部分站点趋势系数通过了95％置信水平检验,山脊以西站点趋势系数为正值,但趋势均不显著.GPD模型的概率分布能很好的拟合FFDI极值,96.5％站点的FFDI极值经验分布和理论分布相一致.20年一遇和50年一遇的FFDI极值空间分布大体一致,在50年一遇极值高值区中FFDI值超过40,低值区的FFDI值普遍低于25.%Based on daily observational data in northeast China region in the period 1961-2010,the forest fire danger index (FFDI) were calculated and Generalized Pareto Distribution (GPD) was also used to fit the extreme value of FFDI,the main results show as following:the high value area of FFDI were located in western Jilin prov ince,western Liaoning province and Chifeng,Tongliao,Hinggan league in Inner Mongolia,and all these areas are basically located in the leeward slope.The distribution of trend coefficient of FFDI were divided into two parts,the stations located to the east of the ridge of the Greater Khingan presented a negative trend and the trend were significant for some stations,the trend were positive for stations west of the ridge of Greater Khingan,but none of them was significant.The probability distribution of GPD model can be well fitted to the extreme value of FFDI,and the empirical distributions of 96.5％ station were consistent with the theoretical distribution.The spatial distributions were substantial agreement for the 20-year and 50-year return values of extreme FFDI,the high value of 50-year return value were greater than 40 and low value were generally less than 25.
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