基于多源实况资料的森林火灾期间的气象特征分析——以西昌“3·30”森林火灾为例  

Analysis of Meteorological Characteristics during Forest Fire Based on Multi-source Live Data——A Case Study of“3.30”Forest Fire in Xichang

作　　者：陈文龙 李兵 程晓龙[2] 陈永攀 陈倩 CHEN Wenlong;LI Bing;CHENG Xiaolong;CHEN Yongpan;CHEN Qian(Meteorological Bureau of Liangshan Prefecture,Xichang 615000,China;Chengdu Institute of Plateau Meteorology of CMA,Chengdu 610072,China)

机构地区：[1]凉山州气象局,四川西昌615000 [2]中国气象局成都高原气象研究所,四川成都610072

出　　处：《灾害学》2023年第1期111-116,共6页Journal of Catastrophology

基　　金：中国科学院A类战略性先导科技专项(XDA23090103);中国气象局创新发展专项(CXF2021Z014)。

摘　　要：基于地面观测资料、四川省雷电监测网、NCEP再分析资料、ECMWF再分析资料以及雷达基数据,从天气实况、大气环流、气象物理量、雷达回波四个方面对西昌“3·30”森林火灾期间的气象特征进行了分析,结果表明:“3·30”森林火灾发生前后,西昌泸山周边气温高、风速大、相对湿度低;在高空低槽、低空切变线、低空急流、地面热低压、地面冷锋的共同作用下,西昌泸山火场附近出现了气温突升突降和偏南大风转偏北大风的现象;对流层中层辐合、低层辐散且中低层存在下沉运动是高空动量下传的重要表现,有利于热低压的维持和地面偏南大风的出现;西昌C波段多普勒雷达对火灾烟尘有较好的探测效果,烟尘回波的强度为5—30 dBZ,随着距火场距离的增加,烟尘回波的水平范围增大,强度减小且底部不再接地,烟尘回波的相对径向速度能近似反映出一定高度上的风向和风速。Based on the surface observation data,data of lightning monitoring network of Sichuan Province,reanalysis data of NCEP,reanalysis data of ECMWF and the basic data of radar,the meteorological characteristics during the“3.30”forest fire in Xichang are analyzed from the weather reality,atmospheric circulation,meteorological physical quantity and radar echo,results indicated that:before and after the fire,the temperature and the wind speed was high and the relative humidity was low around Mt.Lu in Xichang.Due to the joint action of high-altitude low trough,low level shear line,low level jet,warm low pressure and cold front,the sudden rise and fall of temperature and the wind direction conversion of southerly gale to northerly gale occurred near the fire site on Mt.Lu.Convergence in the middle troposphere,divergence in the lower troposphere and subsidence in the middle and lower troposphere were important manifestations of high-altitude momentum downward,which was conducive to the maintenance of warm low pressure and the emergence of southerly gale on surface.Xichang Doppler radar of C-band had a good detection effect on fire smoke.The intensity of the smoke echo was 5-30 dBZ.With the increase of the distance from the fire site,the horizontal range of smoke echo increased,but the intensity decreased,and the bottom was no longer grounded.The relative radial velocity of smoke echo can approximately reflect the wind direction and wind speed at a certain height.Through the depth analysis,the ability and level of meteorological service of forest fire scientific prevention and extinguishing will be improved in Liangshan Prefecture in the further.

关 键 词：森林火灾 气温 风 动量下传 雷达回波 

分 类 号：X43[环境科学与工程—灾害防治] P426[天文地球—大气科学及气象学] S762[农业科学—森林保护学]