DESAF

DESAF is developing the first operational observatory for the annual monitoring of desertification across the whole of France (mainland France and the overseas departments and regions). Using satellite and meteorological data, it enables annual estimates of aridity and land degradation indicators, which are available as open data via an interactive web portal.

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Desertification: Automated Assessment and Monitoring in France

Overview

Context

Desertification (land degradation in arid areas) is now affecting Europe. Nearly 8% of European territory is affected, particularly in the Mediterranean region. In December 2024, France officially joined the list of affected countries and is required to draw up a National Action Plan. Reliable annual monitoring has become essential.

The DESAF (Désertification: Évaluation et Suivi Automatisé en France) project is establishing the first national observatory for the annual monitoring of desertification, covering mainland France and the overseas departments and regions (DROM-COM). Each year, it enables the estimation of three monitoring indicators:

aridity (climate-related)
land degradation (loss of vegetation, changes in land use, decline in soil carbon).
desertification, a combination of the two previous indicators.

Methodology

The methodology is aligned with the reference framework of the United Nations Convention to Combat Desertification (UNCCD) and the European soil degradation indicators provided by the European Soil Data Centre of the Joint Research Centre (JRC).

The indicators are produced at a resolution of 250 m using recent satellite and meteorological data. An automated processing pipeline (open-source R scripts) recalculates the results annually.

Innovations

Adaptation of the method to a temperate country
Combination of UNCCD and JRC indicators for an internationally comparable assessment
An automated, open and reproducible service, applicable across the whole of Southern Europe.

A consortium combining innovation and scientific infrastructure

DESAF brings together three complementary partners. This partnership, combining operational engineering, innovative Earth observation processing and national digital infrastructure, ensures the reliability and sustainability of the project’s deliverables.

Nitidæ is an association that designs and implements projects reconciling environmental conservation with the development of local economies. Drawing on its expertise in remote sensing, geographic information systems (GIS) and soil carbon, it is responsible for project coordination, the design of indicators and the development of the automated processing chain.
CSFD is the French Scientific Committee on Desertification. It ensures the scientific quality of the project by carrying out methodological validation, interpreting results and contributing to training and knowledge dissemination activities.
CNRS / Data Terra is the national research infrastructure dedicated to Earth system observation. It contributes its expertise in geospatial data processing, generates desertification products and indicators, and disseminates the results through the FAIR data services of the THEIA / Continental Surfaces cluster.

Application site(s)

France (mainland and overseas departments and regions)

Data

Satellite

MODIS (NASA) – MOD13Q1 NDVI series, 250 m, 2000→present
ESA CCI Land Cover – annual land cover, 300 m

Other

SAFRAN-ISBA (Météo-France) – precipitation and potential evapotranspiration, 8 km
SoilGrids (ISRIC) – soil organic carbon, 250 m
ESDAC (JRC) – European soil degradation indicators (erosion, salinisation, acidification)

Results – Final product(s)

DESAF will implement an operational web platform, hosted and maintained by Data Terra / THEIA. This platform will ensure the annual updating of three key indicators (aridity, land degradation, desertification) as well as SDG indicator 15.3.1, relating to the proportion of degraded land compared to the total land area, at a resolution of 250 m and dating back to 2016.

Freely accessible (open-source code, open data), the platform will offer an interactive map visualization interface, multi-scale statistical analyses (national, regional and local), and will enable year-on-year comparisons as well as GIS/CSV exports.

References

Bouvier, M., Montfort, F., Grinand, C., Nourtier, M., & Chotte, J.-L. (2025). Évaluation de l'état des terres affectées par la désertification en France métropolitaine https://doi.org/10.5281/zenodo.14957142