to: 29 Sep 2021




ECMWF’s Summer of Weather Code (ESoWC) has launched its fourth edition on 1 February 2021. It aims to bring together teams to solve technical challenges and to work on innovative weather-, climate- and atmosphere-related open-source software solutions.

The Copernicus Climate Change Service (C3S) and Copernicus Atmosphere Monitoring Service (CAMS), which are implemented by ECMWF on behalf of the European Commission, are participating again this year by providing mentors and being featured in some of the challenges teams are asked to work on.

As in previous years, the challenges of the 2021 edition cover a wide range of topics, including machine learning applications and visualisation projects. For the first time, ESoWC will be supported by WEkEO, the Copernicus Data and Information Access Service, a joint initiative by ECMWF, EUMETSAT and Mercator Ocean.

Six challenges that will be highly beneficial to ECMWF’s Copernicus activities have been proposed on Github, where interested parties can submit a proposal on how to tackle the challenge:

  1. Challenge 12: Size, precision, speed -pick two: implementation
  2. Challenge 21: Machine Learning to improve the CAMS global air quality forecasts
  3. Challenge 14: Atmospheric composition data comparison toolbox
  4. Challenge 33: WEkEO in a glance
  5. Challenge 23: Mapping Emissions of Air Pollutants
  6. Challenge 15: The CDS-RTTOV-box

The application period will end on 16 April 2021 and the selected teams for the coding phase will be announced on 30 April 2021. ESoWC’s coding phase between May and the end of August is an intense and fruitful collaboration among mentors and developers, leading to a mutual learning experience. During this time, the initial proposals are implemented into feasible software developments and innovations.

After the coding period, provided that all milestones and deliverables are fulfilled, the developers will receive a stipend of £5,000. The presentation of the final results will be a virtual event, the Final ESoWC Day, to take place in September 2021.

Does this sound like something you would like to be a part of? Learn more about ECMWF’s Summer of Weather Code, this year’s challenges, as well as deadlines, proposal guidelines and other practical information at and as well as on Twitter: @esowc_ecmwf.