A cross-sensor semantic EO data cube to open and leverage essential climate variables with scientists and the public

Short Description

Starting point / motivation

Long time series of essential climate variables (ECVs) derived from satellite data are an important contribution to climate research. They are a critical, independent source of information for comparison with climate model results, but they can also be used to directly detect and monitor changes in our environment.

The Remote Sensing Research Group at University of Bern's Institute of Geography has compiled and archived the longest European time series (1981-2019) of AVHRR data that has been processed using physical methods and algorithms (e.g., lake surface temperature, snow cover, vegetation dynamics).

Contents and goals

In SemantiX, this time series will be complemented and expanded using Sentinel-3 A/B data and made accessible in a newly developed EO-midstream technology, a semantic EO data cube. This technology will be linked to a mobile citizen science application giving the public a new, direct and interactive access point to EO data and derived information products.

SemantiX will combine AVHRR and Sentinel-3 A/B data using new methods to create a unique, long time series that can be carried into the future through continued integration of newly acquired Copernicus Sentinel 3 data. Until now, AVHRR data have only been accessible via sequential access, requiring a significant time investment and expert knowledge to find relevant data for analysis. Interested scientists from other disciplines or the broader public currently do not have any access to these methods or data.


In the scope of this project, a prototypical cross-sensor semantic EO data cube, considered as a new EO-midstream technology, will be created using pre-processed AVHRR satellite data, Sentinel-3 A/B Copernicus data and derived analysis results. The cube will be linked to a smartphone application that will allow a demonstration of semantic queries of ECVs over a long time series (e.g., vegetation dynamics, snow cover over the last few years) as well as providing visualisation targeted to non-expert users. Anyone, whether domain experts, interested citizen scientists or the broader public, can query for changes in their immediate surroundings over time.

Users of this app can contribute their own observations to extend the information available to everyone as well as help in validating semantic query results. The smartphone app will be a prototypical demonstration within an already established citizen science project, Nature's Calendar (i.e., Naturkalender). This app already has an active user community and is actively being tested by students studying at academic partner institutions.

Expected results

The project results from SemantiX contribute to continuing a unique data pool and expanding the portfolio of available EO-midstream technologies. For the first time, various target groups will have simplified access to these EO data and derived information, including ECVs. Scientists from disciplines unrelated to remote sensing, students (i.e., the next generation of scientists) as well as interested members of the public will have direct access to long EO data time series for a variety of applications without insurmountable technical hurdles.

Access will be possible via the Web (i.e., in the browser) as well as using the mobile citizen science application. SemantiX will focus on the Austrian-Swiss alpine region, a European region that is currently experiencing serious changes due to climate change that will continue to create challenges well into the future.

Project Partners


University of Salzburg

Project partner

  • Spatial Services GmbH
  • University of Bern - Institute of Geography

Contact Address

University of Salzburg
Kapitelgasse 4-6
A-5020 Salzburg
Tel.: +43 (662) 8044-0
Fax: +43 (662) 8044-145