Wildfire case studies · Castellón · Spain · 2022
Bejís Fire 2022: Satellite Burn Severity and the Limits of Area Comparisons
Scope: Historical documentary analysis. Spanish primary sources reviewed 2 November 2026; interpretations are identified separately.
The Bejís fire of August 2022 provides a concrete example of how satellite-derived burned area differs from an operational perimeter. The University of Valencia’s published assessment includes image dates, indices and limitations, making it possible to examine the measurement rather than merely repeat a headline number.
What the university product measures
PRISE reports 17,529 hectares of classified burned area for the fire declared on 15 August. Its analysis compares Sentinel-2 tile T30TXK imagery from 8 and 23 August 2022. It uses changes in NBR2 for delineation and vegetation information from pre-fire NDVI, with additional spectral indices used to assign severity classes. Source: University of Valencia, PRISE Bejís assessment.
The product warns that 20-metre resolution, clouds and atmospheric conditions introduce limitations. It also explains that ground-reported outer perimeters may include unburned areas. The published classified area therefore should not be relabeled the definitive official incident perimeter.
Severity is not flame intensity
Tecnobosque interpretation: This product assesses change between observations. It does not measure the flame height or heat-release rate at every location during the fire. A pixel classified at high severity represents the result of the selected method and thresholds; it is not a direct inventory of all dead trees or all soil damage within that pixel.
For a reproducible comparison, retain the product’s observation window and method. A later image may reflect additional burning or vegetation change. A different classification threshold may include different marginal pixels. Without checking those choices, a difference between two maps cannot automatically be called an error.
A useful comparison checklist
| Before comparing two areas | Check |
|---|---|
| Geographic meaning | Classified burned pixels or enclosing perimeter? |
| Observation window | Which pre-fire and post-fire acquisitions? |
| Classification | Which indices, thresholds and vegetation masks? |
| Spatial detail | Which resolution and minimum mapped patch? |
| Validation | Which field observations support the interpretation? |
From a severity map to restoration decisions
MITECO’s 18 October 2022 announcement included urgent works at Bejís and other fire-affected sites. It identified channel obstructions, vulnerable burned vegetation and erosion risk as reasons for action. Its combined area statement for Bejís and Vall d’Ebo is not a Bejís-only measurement. Source: MITECO emergency works announcement.
The ministry’s separate compilation lists approved amounts of €599,748.30 for Bejís and €393,003.25 for Bejís II. These are entries in a restoration-works register, not estimates of total fire damage or proof of ecological recovery. Source: MITECO register of hydrological-forest restoration actions.
What further analysis would require
A severity map can help identify places to examine, but prioritizing a specific slope or channel requires more evidence: terrain, exposed assets, soil conditions, vegetation response and expected rainfall. This page does not turn the satellite classification into a site-specific prescription. Nor does it calculate emissions or health impacts from mapped area.
The main value of this case is methodological transparency. Readers can trace a published number to its images and stated limitations, then compare it with administrative records without assuming that all sources measure the same object. Related reading: Soberanes satellite progression and Sierra de la Culebra restoration evidence.
Cite this analysis: Tecnobosque, “Bejís Fire 2022: Satellite Burn Severity and the Limits of Area Comparisons.” 2 November 2026. Consult the linked original documents for their definitions and findings.