Baijnath-Rodino Janine A, Le Phong V V, Foufoula-Georgiou Efi, Banerjee Tirtha
Department of Civil and Environmental Engineering, University of California-Irvine, Irvine, CA, USA.
Department of Civil and Environmental Engineering, University of California-Irvine, Irvine, CA, USA; Faculty of Hydrology Meteorology and Oceanography, University of Science, Vietnam National University, Hanoi, Viet Nam; Environmental Sciences Division, Oak Ridge National Laboratory, Oak Ridge, TN, USA.
Sci Total Environ. 2023 Apr 20;870:161954. doi: 10.1016/j.scitotenv.2023.161954. Epub 2023 Feb 2.
This study 1) identifies the seasons and biomes that exhibit significant (1980-2019) changes in fire danger potential, as quantified by the Canadian Fire Weather Index (FWI); 2) explores what types of fire behavior potentials may be contributing to changes in fire danger potential, as quantified by the United States Energy Release Component (ERC) and the Ignition Component (IC); 3) provides spatiotemporal insight on how fire danger potential and fire behavior potential are responding in relation to changes in seasonal precipitation totals and seasonal mean air temperature across biomes. Time series of these fire potentials, as well as seasonal mean temperature, and seasonal precipitation totals are generated using data from the 0.25° ECMWF spatial resolution Reanalysis 5th Generation (ERA5) and the Climatic Research Unit gridded Time Series (CRU TS). The Mann-Kendall test is then applied to identify significant spatiotemporal trends across each biome. Results indicate that the September-November season (SON) exhibits the greatest rate of increase in fire danger potential, followed by the June-August season (JJA), December, January-February season (DJF), and March-May season (MAM), and this is predominant over the Tropical and Subtropical Moist Broadleaf Forest Biome, as well as all vegetation types of the temperate biomes. Similarly, the temperate biomes experience the greatest rate of increase in fire intensity potential and ignition potential, but prevalent during the DJF and MAM seasons. Furthermore, there is a significant positive correlation between fire danger potential and seasonal mean air temperature during JJA in the Northern Hemisphere for the temperate biomes in North America and Europe, as well as the Tropical and Subtropical biomes in Africa. Our analysis provides quantitative insight as to how fire danger potential and fire behavior potential have been responding to changes in seasonal mean temperature and seasonal precipitation totals across different ecoregions around the world.
1）确定了1980 - 2019年期间，加拿大森林火险天气指数（FWI）量化显示火险潜力有显著变化的季节和生物群落；2）探讨了美国能量释放分量（ERC）和点火分量（IC）量化的何种火灾行为潜力可能导致火险潜力的变化；3）提供了关于火险潜力和火灾行为潜力如何响应不同生物群落季节性降水总量和季节性平均气温变化的时空洞察。这些火灾潜力以及季节性平均温度和季节性降水总量的时间序列是使用0.25°欧洲中期天气预报中心（ECMWF）空间分辨率第五代再分析（ERA5）和气候研究单位网格化时间序列（CRU TS）的数据生成的。然后应用曼-肯德尔检验来识别每个生物群落的显著时空趋势。结果表明，9月至11月季节（SON）火险潜力的增加速率最大，其次是6月至8月季节（JJA）、12月、1月至2月季节（DJF）和3月至5月季节（MAM），这在热带和亚热带湿润阔叶林生物群落以及温带生物群落的所有植被类型中都很突出。同样，温带生物群落的火灾强度潜力和点火潜力增加速率最大，但在DJF和MAM季节普遍存在。此外，在北半球，北美和欧洲的温带生物群落以及非洲的热带和亚热带生物群落，JJA期间火险潜力与季节性平均气温之间存在显著正相关。我们的分析提供了关于火险潜力和火灾行为潜力如何响应全球不同生态区域季节性平均温度和季节性降水总量变化的定量洞察。
