Wildfire Risk Assessment
Improving wildfire risk assessment with soil moisture data
Experience
The Civil Protection of Veneto is a partner in the MOSAIC project (Managing prOtective foreSt fAcing clImate Change), funded by the Interreg Alpine Space Programme. The project supports climate change adaptation, disaster risk prevention and resilience through ecosystem based approaches. Within this framework, improving wildfire risk assessment is a key priority, as climate change increases the frequency and intensity of extreme events.
Today wildfire risk is commonly assessed using the Fire Weather Index (FWI), which combines weather driven fire spread (ISI) with fuel availability (BUI). While ISI depends on real time weather conditions, BUI is used as a proxy for soil moisture and is calculated from past rainfall. The actual water content in the soil, a key driver of fire susceptibility, is not measured directly. As a result, risk models may fail to fully capture real fuel conditions, limiting the accuracy of risk estimation and early warning.
During a three year proof of concept (2022 to 2025), Finapp installed six CRNS probes at different forest sites across the Veneto region, including Monte Avena and Montegrande, to capture the diversity of local conditions. Using cosmic rays, the probes measured soil moisture on a large scale, in depth and in real time.
The purpose of this collaboration was to combine real soil moisture data with classic weather data to make wildfire risk assessment more reliable.
Use
Comparing BUI with directly measured soil moisture, Finapp found a strong non linear correlation: as soil moisture increases, BUI decreases. Building on this, Finapp developed the Finapp Dryness Index (FDI). Replacing the traditional BUI with the FDI produced a modified FWI that closely matches real conditions, while revealing important differences across the seasons.
In winter with snow cover, the FDI correctly drops to near zero, reflecting the absence of fire risk, while the traditional model may still indicate risk. In winter without snow cover, the FDI captures higher risk levels, consistent with the dry fuel conditions observed in the field. In summer, despite high temperatures, the FDI often shows lower risk levels, reflecting frequent precipitation and higher soil moisture during the warm season.
These findings contributed to the development of Fin4Earth, Finapp’s web based platform for the early warning of landslides, wildfires and floods. Fin4Earth integrates real soil moisture data from Finapp probes into conventional models, defines custom risk thresholds based on each site’s characteristics and historical events, and, by combining local weather forecasts with proprietary AI algorithms, projects risk up to 72 hours in advance.
For the Civil Protection of Veneto, moving from indirect estimation to real observation means a more reliable and seasonally consistent understanding of fire risk, supporting more effective prevention and resource allocation.
“Finapp has developed a dryness index that has shown a strong correlation with existing ones. We were pleasantly surprised by this. We are integrating Finapp into our wildfire risk monitoring platform.”
Benefits
- More accurate wildfire risk estimation, based on real fuel conditions rather than indirect proxies
- Improved seasonal reliability, capturing snow cover and dry winter events
- Finapp Dryness Index (FDI) integrated into the standard Fire Weather Index
- Continuous soil moisture monitoring on a large scale, in depth and in real time
- Site specific early warning tailored to each forest area
- Risk forecasts up to 72 hours in advance with Fin4Earth
- More effective prevention and allocation of resources
