国网辖区火险等级评估及山火时空特性分析

Fire hazard rating assessments and temporal and spatial properties of wildfires in China grid administrative regions

通过中国气象台2015年2月11日16时至4月20日20时周期内发布的全国热源点监测和森林火险气象等级数据,对国家电网辖区内各省份和区位进行热源点和各级(较高、高和极高)森林火险气象等级出现项次和频次进行统计,给出危险性排序并赋予权重后计算总体危险性分级,以此确定较高等级代表性省份,对其2012-2014年代表案例进行时空特性分析。结果发现:统计周期内四川省热源点总体危险性排序为7,四川南部和西部在森林火险气象等级较高区位内对应总体危险性排序分别为2和5,四川西南部、西部和南部在森林火险气象等级高区位内对应总体危险性排序分别为3、4和5,四川西南部在森林火险气象等级极高区位内对应总体危险性排序为1,可作为代表性省份和区位;山火现场通常地形复杂、地势陡峭、天气干燥、风力较大、风向不定、火线漫长、浓烟密集;山火发生主要月份为3月和4月(比例均约为33.3%),主要时段为12:00-18:00(比例约为53.3%),主要火场林相为云南松、冷云杉、栎类和杂草灌木。

Based on the monitoring data of hot spots and forest fire danger weather indexes （three ratings of relatively high. high and extremely high） from Feb. 11 at 16：00 to Apr. 20 at 20：00 of 2015 issued by National Meteorological （;enter of Chi na Meteorological Administration （CMA）, their occurrence i- tems and frequencies were counted for the State C-rid＇s adminis trative regions llke provinces and zones. Total fire hazard rat ings were determined by ranking seven single hazard items and calculating via their weight ratios. The province with higher to taI fire hazard rating was figured out. Its typical wildfire acci dents in 2012 2014 were analyzed. Results show thai Sichua~ Province can be taken as the typical region since its tolal hazard rating of hot spots ranks seventh, the hazard ratings of relative ly high forest fire danger weather indexes for Southern Sichuan and Western Sichuan rank second and fifth respectively, the hazard ratings of high forest fire danger weather indexes for Southwestern Sichuan, Western Sichuan and Southern Sichuan rank third, fourth and fifth respectively, the hazard rating of extremely high forest fire danger weather index for Southwest ern Sichuan ranks first. The spots of wildfires usually hold complex topographies, steep terrains, dry climate, strong wind force, casual wind direction, winding fire fronts and dense fumes. Wildfires usually break out in Mar. and Apr. with por tions of 33.3% and time frames of 12：00--18：00 with a portion of 53. 3%. The primary forest forms on spot are Pinus yuu nanensis, spruce, oak, grass and shrub.