Influence of Rainfall on the Spatiotemporal Dynamics of Wildfires in Guinea

Abstract

The Republic of Guinea, characterized by significant eco-climatic diversity and four major natural regions, has a population heavily reliant on natural resources. Rainfall plays a crucial role, influencing not only agriculture and water availability but also the dynamics of bushfires. These fires are a recurring phenomenon, linked to human activities (slash-and-burn agriculture, hunting, and pasture management) and climatic conditions. However, few studies have thoroughly explored the relationship between rainfall patterns and bushfires, despite these interactions being crucial for the sustainable management of ecosystems and the prevention of environmental risks. The overall objective of this study is to analyze the spatio-temporal impact of rainfall indices on wildfire dynamics in the Republic of Guinea, in order to make a dual scientific and operational contribution: understanding climatic mechanisms and supporting public policy. The data used come from satellite rainfall estimates from the CHIRPS (Climate Hazards Group InfraRed Precipitation with Station data) product, covering the period 2010 - 2018, as well as wildfire data from the AVHRR-LTDR Burned Area Grid v1.1 product, allowing for the assessment of the spatial and temporal dynamics of burned areas and the intensity of wildfires. The methodology is based on the calculation of monthly and annual climatology, the analysis of standardized anomalies, and the correlation between rainfall and burned areas. The results show a clear inverse relationship between rainfall and wildfires. Burned areas peak in January-February and November-December, periods of extreme drought, and almost completely disappear during the rainy season (June-September). Spatially, fires are more intense in the east and southeast during the dry season, while they become almost nonexistent during the wet periods. Standardized anomalies confirm a negative correlation between rainfall and burned areas, although this correlation is not statistically significant over the period 2010–2018. Finally, this study reveals the crucial role of rainfall patterns in the seasonal and spatial regulation of wildfires in Guinea. It highlights the need to integrate rainfall indices into prevention and adaptation strategies in the face of climate change, while also taking into account human activities.