【摘要】 高火险时段是形成森林火灾重灾时段（年、季）的必要外部环境条件，也是可燃物安全管理的重要依据［１］。本文运用异常度法、分析了大兴安岭林区高火险时段年及其前后各３年、北半球副热带高压面积指数的变化及具规律。研究发现，北半球副热带高压面积指数具有在高火险时段前３年的４月至前１年的９月持续呈负距平、而在当年１～２月呈正距平的规律，为高火险时段的超前预测预报．提供了理论依据。更多还原

【Abstract】 The MDPFF is a necessary external environmental factor forming serious forest fire period(year,season)and is also an important basis for the safe management of fuel.By means of the anomaly degree method, the variation and its regulation of the index of SHPZNH in the year of the MDPFF and each three years before and after this year in Daxing’an Mountains were analysed in this paper.It discovered that the index of SHPZNH appears negative departure from April of the previous third year to September of the previous first year of the MDPFF and appears positive departure from January to February of the present year of the MDPFF.This regulation provides a theoretical basis for prediction and forecast of the MDPFF in advance.更多还原