The Copernicus Global Land Service (CGLS), opens an external URL in a new window is a component of the Land Monitoring Service, opens an external URL in a new window of Copernicus, opens an external URL in a new window, the European flagship programme on Earth Observation. It systematically provides in near-real-time a versatile portfolio of state-of-the-art products on biophysical variables, describing the state of Earth’s land surface to monitor the vegetation, the water cycle, the energy budget and the terrestrial cryosphere. The CGLS offers its rich portfolio on geophysical variables on an open and free basis, to users worldwide.

The Remote Sensing Group at TU Wien’s GEO Department developed the scientific algorithms and processing chains for the products Surface Soil Moisture (SSM) and the root-zone Soil Water Index (SWI), which are among the top-ranked datasets in the CGLS user statistics. Together with our partners at the Earth Observation Data Centre (EODC), opens an external URL in a new window and GeoSphere Austria, opens an external URL in a new window, we develop and maintain the production software of these products, and also monitor the product’s quality and consistency on a regular basis. The soil moisture data is available as daily image products in near-real-time (NRT), one global SWI product at the 0.1° sampling (~12 km), and over Europe at a 1km sampling a SWI and a SSM product.

CGLS soil moisture products over western Europe

© GEO Department

A sequence of five days of the CGLS soil moisture products during August 2018, when several summer storms brought rain to western Europe. In the SSM1km product (first four images) observing the conditions in the surface top soil, the two-satellite constellation of Sentinel-1A and -1B were able to capture a highly dynamical interplay of rainfall and drying periods in western Europe, while sections with no satellite overpass remain as observational gaps. The SWI1km product (fifth image) estimates the less fluctuating conditions in the deeper root soil layers, through the aggregation and filtering the SSM dynamics of the previous days. In this process, the SWI1km product combines observations from the Sentinel-1 and Metop-ASCAT satellites and thus achieves a complete coverage every day.

In the 2024-25 timeframe, several algorithmic enhancements developed in dedicated research activities co-funded by Austrian Space Applications Programme (ASAP), opens an external URL in a new window, Austrian Development Agency (ADA), opens an external URL in a new window, and European Space Agency (ESA), opens an external URL in a new window will be implemented in the CGLS operational production chains. The improvements include a dynamic vegetation modelling and the masking of snow and frozen soil or seasonal water bodies and floods. At the final phase of these so-called CGLS evolution activities, an extension of the 1 km soil moisture products to global coverage will be carried out, reaching out local users worldwide.