Impacts of climate change and deforestation on fire risk in the Amazon basin

Abstract

Fires in the Amazon rainforest are a result of anthropogenic activity in the region. As the Amazon rainforest becomes vulnerable to fire through deforestation and climate change, it is imperative to understand how the fire risk will change in future years—not only for the potential of the forest to become a source of carbon to the atmosphere if burned but also for the potential loss of unique biodiversity and its critical role in regional and global climate. Therefore, we used the Eta regional climate model driven by 3 global climate models to simulate 2 distinct scenarios: one with a high CO2 emission (RCP8.5-DEF15) path and another with a high CO2 emission path and the total deforestation of the Amazon rainforest (RCP8.5-DEFTOT). Combining the multi-model ensemble of temperature and precipitation, we calculated the Keetch-Byram Drought Index (KBDI) and analyzed the results for the dry and wet seasons. In both scenarios, precipitation is reduced and maximum temperature increased. The greatest changes occur during the dry season and with the RCP8.5-DEFTOT scenario. In RCP8.5-DEF15, the KBDI is greatly affected, showing positive anomalies in both seasons. With the addition of deforestation, the fire risk is further exacerbated, thus highlighting the role of the forest in suppressing optimal conditions for fire. Additionally, more than half of the basin area is predicted to experience a high risk of fire in extreme years. Our results emphasize the importance of reducing global emissions and deforestation of the Amazon, given that fire activity could threaten the future of the Amazon rainforest.