Evaluation of the Impact of Climatic, Morphometric, and Geophysical Factors on Thunderstorm-Ignited Wildfires in the Altai Republic

The results of a study of the contribution of climatic and geophysical conditions of the terrain to thunderstorm fire danger in the Altai Republic are presented. The research utilized information on natural fires recorded in the Altai Republic from 2016 to 2020. Climatic and geophysical characteristics of fire locations were determined based on SRTMGL3, EIGEN-6C4, EMAG2, WorldClim 2.1 data. Information on lightning discharges was provided by the WWLLN network. Data processing was conducted using factor analysis based on the principal component method. The study revealed that the largest variance (46 %) in the considered data was attributed to differences in climatic characteristics (annual mean temperature, precipitation, and lightning density), which were in turn influenced by changes in elevation above sea level. The first principal component, combining these characteristics, can be used as a comprehensive indicator to classify fires with similar climatic parameters and landscapes. The second largest variance (14.8 %) was determined by annual average lightning density and values of magnetic and gravitational anomalies at fire locations. It was demonstrated that the values of the second principal component reflect an increasing trend in lightning density with higher values of magnetic and gravitational anomalies in the studied area. The application of factor analysis based on principal component method allowed for the determination of typical climatic and geophysical conditions contributing to thunderstorm fires in the investigated territory