- February 21, 2018
- Posted by: EARSC
- Category: Archive
The web map of Open Data Sicilia showing the Emergency Management activations in summer 2017
The Copernicus Programme, with over 12 TB of Earth Observation (EO) data generated daily, is the third largest data provider globally. Our full, free and open data policy allows anyone anywhere in the world to access and use the data and information. But that is not the full picture. There is another community that often provides an important link to these vast amounts of data and the end user by providing tools, plug-ins and libraries to handle the data and make it easier for the end users to use it – this community is organised under the umbrella of the Open Source Geospatial Foundation (OSGeo).
The Open Data Institute defines good open data as follows:
*It can be linked to for easy sharing
*It is available in a standard, structured format
*It has guaranteed availability and consistency over time
*It is traceable to its sources
These are the guidelines that we follow for Copernicus data and information. We are constantly striving to make the data easier to access, simpler to share, and more relevant to support your research or solve your business problem with EO. The upcoming Copernicus Data and Information Access Services (to be operational in mid-2018) will represent a considerable leap forward in this mission.
In this Copernicus Observer, we shall showcase some examples of tools linked to Free and Open Source Software (FOSS) initiatives. We will show how these tools make access, processing and visualisation of Copernicus data and information more approachable and open, and how community resources invested into FOSS are boosting the growth of the Copernicus ecosystem.
Accessing Copernicus Sentinel Data
There are many different official access portals for Copernicus data, however, especially for using the Sentinel satellite data, you do need to have remote sensing experience. Some of the GIS (Geospatial Information Systems) enthusiasts recognised this problem and developed software to solve it.
If you’re using open source GIS software, you might be interested in Sentinel Hub, a free (for non-commercial use) web service that allows you to create Web Mapping Services (WMS) instances of Sentinel data and derived images and indicators. You can plug in satellite data into your GIS without downloading it or needing to convert it to a format that is usable in a GIS. The operators of the Sentinel Hub have even created a QGIS plugin so you can create WMS instances of Sentinel data directly inside QGIS (an open source GIS software). When the DIAS platforms become operational this offer of alternate and free of charge access points will be significantly widened.
Readers who have more experience with geospatial data and GIS software, and have used satellite imagery before, can try a fully free and open source Semi-Automatic Classification Plugin in QGIS. This plugin allows to download Sentinel-2 scenes directly into QGIS. At the same time, the plugin allows you to directly process the data into a more useful information product. You can for instance generate reflectance values, calculate spectral indices such as the Normalized Difference Vegetation Index (NDVI) or perform a classification on the data you have downloaded.
Processing Sentinel images
For more advanced users, remote sensing experts and scientists who prefer to work directly with the data, the best choice is the free and open source SNAP Toolbox. Its development was funded by the European Space Agency. SNAP provides all elements you need for opening and processing Sentinel-1, -2 and -3 data to higher level products. It is possible to develop Python plugins to extend the current toolset, and to automate processes using batch-processing. The toolbox is complemented by a very useful community forum.
Visualising data and information
The Copernicus Programme also offers higher-level information products, mostly but not exclusively based on Sentinel data. Information products from the Marine Environment, Land, Atmosphere, Climate Change and Emergency Management Services are also freely and openly accessible. Visualisation of Copernicus data and information is essential to extract their value for use in operational processes. Free and Open Source Software tools can again be useful when working with these information products. Two examples can be seen here.
Raster data often come in formats that scientists in the marine and atmosphere fields are familiar with, but which are not always easily readable by a standard GIS. This video shows how to visualise data from the Copernicus Marine Environment Monitoring Service, in NetCDF format, with QGIS.
Another free software that allows you to read NetCDF, HDF and GRIB formats, although not open source, is Panoply.
An Example of Copernicus Data in Action
Copernicus is an ambitious programme that will continue growing and improving. To do so, it needs the open source community, and other enthusiastic developers, creators and users – because only by working all together will we achieve the true goal of Copernicus – making our planet healthier, safer and better.