Spatial and Temporal Patterns of Wildfires in the Basque Country (1995-2022)

Wildfires represent a growing challenge for weather and climate science, with significant impacts on ecosystems, air quality, infrastructure, and human safety. In the Basque Country (CAE), wildfire ignition is predominantly driven by human activity, but understanding spatial and temporal patterns provides crucial insight into the interaction between environmental conditions and anthropogenic behavior. Characterizing these patterns supports predictive modelling, early-warning systems, and risk management strategies under both current and changing climate conditions.

Wildfires in the CAE show complex spatial and temporal patterns driven by both environmental and human factors. This study analyzes a dataset of 5,053 wildfire incidents recorded between 1995 and 2022, including small fires (<1 ha), medium fires (1–50 ha), and large fires (>50 ha), providing a comprehensive overview of wildfire dynamics over more than two decades.

Results indicate that small fires are the most frequent type of incident (54.9% of all events) but contribute minimally to the total burned area (3.8%), while medium (43.7% of events; 51.9% of burned area) and large fires (1.4% of events; 44.2% of burned area) dominate landscape-level impacts. Monthly patterns reveal that fire frequency peaks in March (829 events), whereas burned area reaches its maximum in February (~3,200 ha). Spatial analysis across historical territories shows broadly similar patterns, with small fires dominating in all provinces (52–58%). However, Araba exhibits a slightly higher proportion of small fires (57.7%), while Bizkaia shows a greater relative contribution of medium fires (47.0%), and Gipuzkoa presents an intermediate distribution.

Temporal analysis reveals clear weekly and hourly patterns: ignitions peak during weekends and during the late afternoon, with a maximum around 16:00, reflecting the predominance of human-driven fires. Most fires (98.3%) are controlled within 24 hours, although large fires show significantly longer durations (mean 27.3 hours) compared to medium (5.2 hours) and small fires (2.6 hours). Fire size distributions indicate that a very small proportion of large events contributes disproportionately to total burned area, consistent with heavy-tailed behavior observed in other temperate fire regimes.

These results provide an updated and comprehensive overview of wildfire dynamics in the Basque region, corroborating patterns strongly influenced by human activity. Spatial and temporal variability further highlights the value of territory-specific management strategies