Sun Chenling, Touge Yoshiya, Shi Ke, Tanaka Kenji
Disaster Prevention Research Institute, Kyoto University, Gokasho, Uji, Kyoto, 611-0011, Japan.
China Institute of Water Resources and Hydropower Research, Beijing, 100038, China.
Sci Rep. 2024 Oct 10;14(1):23759. doi: 10.1038/s41598-024-75563-2.
Drought is the primary driver of wildfires in humid regions, and the main drought drivers for wildfire occurrence and spread vary across different humid climatic areas. This study explores the suitability of different drought descriptions for wildfires under various humid temperate climates in Japan. Based on wildfire data from 1995 to 2012, statistical and correlation analyses were conducted to examine the performance of effective humidity (EH) and soil moisture (SM) as indicators of atmospheric and soil drought. EH is used for nationwide wildfire and drought warnings in Japan. The results show that EH is significantly influenced by seasonal and regional factors, with its ability to assess drought for wildfire varying accordingly, whereas SM demonstrates a more consistent ability to assess drought across different seasons and regions. Correlation analysis revealed that atmospheric drought better explains the drought conditions for wildfire ignition in 11 prefectures, mainly concentrated in the northern regions along the Sea of Japan. In contrast, the correlation coefficients for SM were higher in 33 prefectures, particularly along the Pacific coast, indicating that soil drought better explains the drought conditions for burned areas in these prefectures.
干旱是湿润地区野火的主要驱动因素，不同湿润气候区域野火发生和蔓延的主要干旱驱动因素各不相同。本研究探讨了在日本不同湿润温带气候下，不同干旱描述对野火的适用性。基于1995年至2012年的野火数据，进行了统计分析和相关性分析，以检验有效湿度（EH）和土壤湿度（SM）作为大气干旱和土壤干旱指标的性能。EH被用于日本全国范围的野火和干旱预警。结果表明，EH受季节和区域因素的显著影响，其评估野火干旱的能力也相应变化，而SM在不同季节和区域表现出更一致的评估干旱的能力。相关性分析表明，大气干旱能更好地解释日本海沿岸北部地区11个县野火着火点的干旱状况。相比之下，33个县（特别是太平洋沿岸地区）的SM相关系数更高，这表明土壤干旱能更好地解释这些县过火面积的干旱状况。
