O3as: an online ozone trend analysis service within EOSC-synergy

O3as is a service within the framework of the European Open Science Cloud-Synergy (EOSC-Synergy) project supporting scientists working on the Chemistry-Climate Model Initiative (CCMI, http://blogs.reading.ac.uk/ccmi/ccmi-phase-two/) for the quadrennial global assessment of ozone depletion (https://www.esrl.noaa.gov/csl/assessments/ozone/2018/). The next assessment will be due in 2022. 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. O3as shall provide an invaluable service to extract ozone trends from large data volumes created by climate projection models producing figures of stratospheric ozone trends in publication quality, in a coherent way. A web application shall be provided where a user configures their requests to perform simple analyse. This request is passed to the O3as service via an O3as REST API call. There, the O3as service processes the request, where the reduced data set is accessed via WebDAV and OIDC. In order to produce a reduced data set, regular tasks are run on an HPC to copy primary data and perform data preparation (e.g. ... mehrdata reduction and parameter unification). O3as uses EGI Check-In to access certain functionalities of the service, the OIDC-Agent and rclone to mount data servers using WebDAV—HTTP authentication, udocker (a tool to execute simple docker containers in multi-user space without root privileges) to perform data reduction in the HPC environment, and an infrastructure manager to deploy service resources (Kubernetes).