Value-Adding Products and Algorithms for Land Surfaces

Theia at a glance

Theia is pursuing four main objectives :

  1. Promoting and facilitating the use of space data, for science and public
    actors, in terms of  imagery, added-value products as well as in-situ data;
  2. Developing added -value products and services for the science communities
    and national public actors;
  3. Developing networks of competences
  4. Supporting French realizations at European and international level.

Observing Earth

Theia is now one of the active members of the Earth System Research Infrastructure, Data Terra.

Along, three other French Earth Observation consortia:

  • Aeris – the French thematic consortium on Atmosphere
  • ForM@Ter – the French thematic consortium on Solid Earth
  • Odatis – the French Thematic consortium on Ocean spatial observation.
  • and Dinamis, the French pooled system for access to satellite imagery.

Theia in images

Theia offers monthly surface reflectance syntheses for the Iberian peninsula. Here a synthesis of cloudless observations over 45 days for the month of August 2019. Theia offers monthly surface reflectance syntheses for Metropolitan France. Here a synthesis of cloudless observations over 45 days for the month of September 2019. Theia offers monthly surface reflectance syntheses for the Italian peninsula. Here a synthesis of cloudless observations over 45 days for the month of September 2019. Localisation of all Hydroweb virtual stations in November 2020 Theia Hydroweb product documenting the level of lakes and rivers. Here the Loire River (France) variations from 2008 to 2019 The product Theia Inland Water Quality measures, among other things, the level of suspended solids. Here in the Rhône at Arles in December 2016. Soil moisture measured by SMOS-IC, summer 2017 Soil moisture measured by SMOS-IC, summer 2018 Gabon biomass map with a 50x50m resolution, Above-ground biomass map of of the savannahs and woodlands of continental Africa and Madagascar at a resolution of 50m x 50m. This DHI mapping is designed for biodiversity assessment and for describing the natural habitats of different species. Artist's view of a β diversity mapping obtained with the application of biodivMapR on an area of the Peruvian Amazon. Theia product presenting the irrigated crops in 2015 in the South-West of France. Produced from 13 LANDSAT8 level 2A images. Carte d'humidité du sol à THRS à l'échelle parcellaire pour la région d'Arles. Binary "urban/non-urban" classification obtained from Sentinel-2 images for the city of Brussels in 2018. Binary "urban/non-urban" classification obtained from Sentinel-2 images for the city of Perpignan 2018. Binary "urban/non-urban" classification obtained from Sentinel-2 images for the city of Strasbourg 2018. Theia Land Cover for Metropolitan France, 2018. 23 classes. Available both at raster et vector formats. Theia 2018 Land Cover Product for Lot-et-Garonne region (France) Theia Land Cover Product for Paris (France) 2018 Theia Reunion Land Cover Product distinguishes 11 classes of land uses. Produced by synthesis of Sentinel-2 and Spot-6 data, its resolution is 1,5 m. Map of the snow coverage in the Pyrenees during a hydrological year (1 September 2016 to 31 August 2017) produced by synthesis of Theia snow-covered surface products. Theia L2-Snow Product detects the presence of snow (in blue) and cloud (in white). Cartography of annual snow coverage for the Alps in number of days between 1st of September and 20 of January for the years 2017, 2018, 2019. Advancing ice front, Quirlies and St-Sorlin glaciers. Spot 6-7. 2014-2019. Mapping Tiger Mosquitoes risk in Montpellier (France). Senegal - Spatial distribution of mosquitoes carrying Rift Valley Fever GeoV2 FCover, October 2019

Latest news

ForM@Ter and THEIA release a serie of very high resolution topographic models of 140 glaciers worldwide through the PGO FAIR collection

The Pléiades Glacier Observatorywas initiated in 2016 by French Space Agency (CNES), by the Laboratoire d’Etudes Géophysiques et Océanographiques Spatiales (LEGOS) and by the Institut National des Sciences de l’Univers […]

MAJA is already ready for CAMS

From the end of September, the MAJA processing chain will be using CAMS 48r1 data for the production of Theia Surface Reflectance products.

A World Glacier Atlas to understand glacier mechanisms in a global warming context

The 3 glacier products available on Theia offer an unprecedented global overview of the evolution of glaciers.


But also

Hydroweb | More than 22800 stations on the world’s rivers

The database Hydroweb offers River Height and Lake Height products derived from spatial altimetry. These time series provide the height of rivers and the height of lakes and reservoirs around the world […]

Land cover Theia product update

Like every year at this time, you’re invited to discover the new version of the OSO product, from the S.E.C Land cover. The 2022 version was released a few days […]

A new GeoDEV website, with resources tailored to your profile

The website of the ART GeoDEV, the Theia Regional Animation network that CIRAD, IRD and CNES have been leading since 2017 in the direction of Southern countries, is evolving to […]

Exemple de traitement Arbocarto pour Mayotte, avril 2023

May 2023, Montpellier | Arbocarto user meetings

Three days of workshops for users of the Arbocarto tool were organised in Montpellier and in “hybrid” mode, from 9 to 12 May 2023. These days were organised in hybrid […]


The development of CAMS aerosol products requires MAJA to be adapted and has an impact on the production of Reflectance Theia products.

Kakhovka: HYDROWEB data shows a reservoir turned back a river

Hydroweb data is used to track the world’s major rivers and reservoirs. It documents the end of the Kakhovka reservoir.