Estimating wildfire potential in Taiwan under different climate change scenarios

Abstract

Wildfires are a significant environmental hazard that pose threats to ecosystems, human livelihoods, and infrastructure. The impact of climate change on wildfires has been widely documented, and Taiwan, an island in East Asia, is no exception to this phenomenon. Given the increasing frequency and intensity of drought conditions in recent years, there is a pressing need to better understand and predict future wildfire risk in Taiwan. In this study, we evaluate changes in wildfire potential during historical and future periods based on satellite observation and regional downscaled projection data. Additionally, we investigate the relationship between past climate conditions in Taiwan and the occurrence of wildfires to gain insights into the characteristics of wildfires and estimate future wildfire frequency under the influence of climate change. Our findings reveal a significant upward trend in historical temperature and wind speed in Taiwan, accompanied by increased variability in rainfall and humidity, and the alternation of which has resulted in a significant increase in wildfire risk. Notably, wildfires in Taiwan are found to be more influenced by the degree of dryness rather than extreme high temperatures. When compared to the baseline of the average wildfire occurrences in recent years (1992–2021), the projected increase in the late twenty-first century (2070–2099) is approximately 35.6% under the RCP8.5 scenario. The wildfire potential during the fire seasons in the southwest and northeast regions of Taiwan is projected to experience an increase of 51.8–90.6% and 40.0–50.0%, respectively. Conversely, wildfire occurrences are projected to decrease by about 12.2% under the RCP2.6 scenario, suggesting that reducing global warming could potentially mitigate the enhanced wildfire potential. These findings provide concrete information that can inform policy decisions and actions to address the increasing wildfire risk in Taiwan. They also emphasize the need for continued monitoring and research to better understand the complex interplay between climate change and wildfire occurrences in Taiwan.