Data access

ids.equipex-geosud.fr

  • Occitanie Region (France): Soil moisture maps available for the period between September 2016 and March 2019.
  • Provence-Alpes-Côte-d’Azur Region (France): Soil moisture maps available for the period between September 2017 and April 2019
  • Beqaa (Lebanon): Soil moisture maps available for the period between September 2017 and April 2019
  • Agia (Greece): Soil moisture maps available for the period between September 2017 and September 2018
  • Düren (Germany): Soil moisture maps available for the period between September 2017 and December 2018
  • Sardinia (Italy): Soil moisture maps available for the period between September 2017 and September 2019.
  • Vienna (Austria): Soil moisture maps available from September 2017 to September 2018
  • Haouz (Morocco): Soil moisture maps available from October 2017 to September 2018

Presentation

The “Soil moisture with very high spatial resolution” SEC offers soil moisture maps with frequent repetition (a map every six days) at the sub-parcel scale on several sites in France, in Europe and around the Mediterranean basin.

Algorithms were developed and moisture maps produced with the support of IRSTEA (UMR TETIS) and CNES (TOSCA Project). This work was carried out in close collaboration with Mehrez Zribi at CESBIO.

The data used come from the Sentinel-1 radar and Sentinel-2 optical Copernicus image series. The radar signal inversion algorithm uses neural networks. It is applied to agricultural parcels (with or without vegetation) extracted from the 2016 and 2017 land cover maps produced by the Theia Land Cover SEC (Jordi Inglada et al., CESBIO).

Sentinel-2 images were used to calculate the NDVI (normalized difference vegetation index). This index is a necessary input for the inversion algorithm, both in order to divide the agricultural areas resulting from the land cover map and to simulate the contribution of vegetation to the total radar signal received by the satellite. Segmentation allows homogeneous polygons inside agricultural parcels to be extracted, and, as a result, allows objects to be offered that are finer than the outline of the parcels.

Thanks to a large field campaign close to the city of Montpellier (almost 500 in situ measurements), the precision for the soil moisture estimate reaches 6 vol.%.


The two moisture maps below use two radar images from 19 and 26 January 2017 over a small area of the Occitanie region. The 19 January 2017 map shows that the soil of the study site is dry, with humidity values between 5 and 15 vol.%. The 26 January 2017 map shows humid soils, with humidity values between 25 and 35 vol.%.

Authors

Nicolas Baghdadi (Tetis), Mohammad El Hajj (Tetis), Hassan Bazzi (Tetis), Michael Aaron Arhinful (Tetis) et Mehrez Zribi (Cesbio)

Contact

Nicolas Baghdadi
IRSTEA, Tetis
ResearchGate
@N.Baghdadi

Mehrez Zribi
CNRS | Cesbio
ResearchGate
@M.Zribi