重庆两场森林火灾蔓延特征的数值模拟  

Numerical Simulation Study on Spread Characteristics of Two Wildfires in Chongqing

作　　者：王宇虹[1] 陈仲榆 杨晓丹[1] 赵鲁强[1] 袁晓玉[1] 梁莉[1] WANG Yuhong;CHEN Zhongyu;YANG Xiaodan;ZHAO Luqiang;YUAN Xiaoyu;LIANG Li(CMA Public Meteorological Service Center,Beijing 100081)

机构地区：[1]中国气象局公共气象服务中心,北京100081

出　　处：《气象科技》2024年第2期205-217,共13页Meteorological Science and Technology

基　　金：国家重点研发计划(2022YFC3003004);国家重点研发计划(2020YFC1511602);中国气象局创新发展专项(CXFZ2023P066);中国气象局公共气象服务中心创新基金项目(Y2022007)共同资助。

摘　　要：为了深入认识同时段内发生的两场森林火灾蔓延特征以及大气、地形等对不同林火行为的影响,进而为多起林火扑灭火工作提供科学支撑,选取2022年8月17日发生在涪陵两场森林火灾,利用高分辨率地理信息、植被数据和气象数据对两场林火行为进行分析研究,同时运用林火大气耦合WRF-Fire(Weather Research and Forecasting Model with Fire Module)模式进行数值模拟。研究发现:①受深厚高压控制,两场林火是在持续高温、干燥背景下发生的,气象干旱等级达到重旱,火险气象等级高。②模式模拟风向风速变化与实况较为一致,基本体现出火场风向和风速突变,表明WRF-Fire模式可以较准确地再现火场蔓延情况。③基于林火蔓延特征时间和空间变化可将大梁山林火发展分为6个阶段、北山坪林火分为4个阶段,造成直线距离相隔4.4 km两个火场蔓延发展程度不同的原因在于地形差异造成的局地风场差异。In order to gain a deep understanding of the spread characteristics of two wildfires that occur simultaneously,as well as the impact of atmosphere,terrain,and other factors on different wildfire behaviours,and to provide scientific support for extinguishing multiple wildfires.Two wildfires that occurred in Fuling on August 17,2022 are selected to analyse and study the behaviour of the two wildfires using high-resolution geographic information,vegetation data,and meteorological observations.At the same time,numerical simulation is conducted using the wildfire-atmosphere coupled WRF-Fire model(Weather Research and Forecasting Model with Fire Module).The research results are found as follows.(1)Under the control of deep and high pressure,the two wildfires break out under the background of continuous high temperature and dryness.Ten days before the wildfire,the daily average temperature is 5.2-8.8℃higher than the same period as usual,the daily maximum temperature is 6.2-8.4℃higher than the same period as usual,and the daily average relative humidity is 26.3%lower than the same period as usual.The drought meteorological level reaches severe drought,and the fire risk meteorological level is high or extremely high.(2)The test results show that the simulated wind direction and wind speed changes of the model are relatively consistent with the actual situation,basically reflecting the sudden changes in wind direction and wind speed of the fire site,indicating that the WRF-Fire can accurately reproduce the spread of multiple real fire sites at the same time.(3)The analysis of temporal and spatial changes in wildfires spread characteristics indicates that the wildfire development in Daliangshan can be divided into 6 stages during this simulation phase,and the wildfire in Beishanping can be divided into 4 stages.The main reason for the difference in the spread and development of the two fires with a linear distance of 4.4 km is the difference in local wind fields caused by differences in terrain.There is a southwest-nort

关 键 词：重庆 林火大气耦合模式 林火蔓延特征 数值模拟 

分 类 号：P435[天文地球—大气科学及气象学]