O3AS is a service mainly for scientists working on the CCMI (http://blogs.reading.ac.uk/ccmi/ccmi-phase-two/) and writing the quadrennial global assessment of ozone depletion (https://www.esrl.noaa.gov/csl/assessments/ozone/2018/).

The recent ozone assessment report consists of six chapters and five appendices with about 25 people actively working on each chapter and a multitude of people working in support of the preparation of the document. The O3AS service shall provide an invaluable tool to extract ozone trends from large climate prediction model data to produce figures of stratospheric ozone trends in publication quality, in a coherent way. Figure shows the architecture of the O3AS technical service. O3as service is split in several actions and components:

Architecture of the O3AS Thematic Service.


A user configures his/her request in the Web Application.


This request is passed to O3as service via the O3as REST API call.


O3as service processes the request, where the pre-processed data (aka skimmed data) is accessed via WebDav and OIDC.


In order to produce skimmed data, regular tasks run on HPC to copy primary data and perform data preparation (e.g. data reduction and parameter unification).

O3AS thematic service includes or will include the following services listed in the EOSC marketplace:

  • EOSC OIDC providers, e.g. EGI Check-In: to access certain functionalities of the service.
  • OIDC-Agent: To mount data servers using WebDAV – HTTP authentication.
  • udocker: To perform data skimming in the HPC environment.
  • Infrastructure Manager: To deploy service resources (e.g. K8s).