Environmental drivers of burned area and fire severity during the 2025 extreme fire season in the NW Iberian Peninsula

[EN] Background Wildfires have long shaped the ecosystems of southwestern Europe, but in recent decades, their frequency, size, and severity have become a widespread socio-ecological threat. In this study, we assessed the 2025 extreme fire season in the north western Iberian Peninsula through remote...

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Detalles Bibliográficos
Autores: Beltrán Marcos, David, Calvo Galván, María Leonor, Fernández Guisuraga, José Manuel
Tipo de recurso: artículo
Estado:Versión publicada
Fecha de publicación:2026
País:España
Institución:Universidad de León
Repositorio:BULERIA. Repositorio Institucional de la Universidad de León
OAI Identifier:oai:dnet:buleria_____::0392f206d70e3506fef7047360d4aa55
Acceso en línea:https://link.springer.com/article/10.1186/s42408-026-00465-9
https://hdl.handle.net/10612/28104
Access Level:acceso abierto
Palabra clave:Botánica
Ecología. Medio ambiente
Ingenierías
Extreme wildfire events
Fire severity
Fuel amount
Fuel type
Iberian peninsula
Vapor pressure deficit
Remote sensing
3106 Ciencia Forestal
2508 Hidrología
3308 Ingeniería y Tecnología del Medio Ambiente
2417 Biología Vegetal (Botánica)
Descripción
Sumario:[EN] Background Wildfires have long shaped the ecosystems of southwestern Europe, but in recent decades, their frequency, size, and severity have become a widespread socio-ecological threat. In this study, we assessed the 2025 extreme fire season in the north western Iberian Peninsula through remote sensing and modelling workflow aimed at identifying drivers of burned area and fire severity. Large wildfires (≥ 500 ha) occurred during the summer fire season (June–September) were extracted from the EFFIS database, while Sentinel-2 imagery was used to estimate spectral fire severity. Pre-fire vegetation, topography, and fire weather were integrated as explanatory variables by fitting separate Random Forest (RF) regression models. Results Our results revealed that a total of 66 large wildfires burned over 520,000 ha across Spain and Portugal, with only one-quarter of these events accounted for over 75% of the total burned area. Grasslands, shrublands, and transitional shrub-woodlands were the most affected land cover types, with protected areas disproportionately affected mainly in NW Spain where 40% of burned area was located in Natura 2000 sites. Fire severity patterns were also remarkable, with high and moderate-high severity classes exceeding 65% of the total burned extent. RF models revealed that this anomalous burned area was driven by top-down atmospheric drivers, particularly exceptionally high vapor pressure deficit (VPD > 4 kPa), strong winds and drought conditions during prolonged heatwave periods. Conversely, fire severity was mainly associated with bottom-up drivers, namely high fuel loads, extensive forest cover, and complex topography. Conclusions Our findings indicate the need to strengthen adaptive management strategies into conservation and land-use policies in order to reduce fire hazard and associated ecological impacts under worsening climatic conditions