ECMWF, as the Entrusted Entity for the Copernicus Climate Change Service (C3S), invites tenders for the provision of Essential Climate Variable (ECV) products and services in the domain of atmospheric composition, specifically for Carbon Dioxide and Methane, Ozone, and Aerosols Properties. The purpose of this Invitation to Tender (ITT) is the provision of operational services aimed at ensuring dependable access to high-quality, consistent, and globally homogeneous satellite climate data products via the Climate Data Store (CDS) in the domain of atmospheric composition.

ECMWF intends to award a single Framework Agreement for a period of maximum 44 months, which shall be implemented via a single Service Contract expected to commence in May 2024.

The services shall include the following technical activities:

- Operation and maintenance of processing systems to generate CDR / ICDR datasets (unless these operations are supported by other initiatives).

- Implementation and/or improvement of operational production chain components as needed to achieve Full Operational Capacity.

- Provision of access to datasets via the CDS.

- Quality assurance and validation of the resulting datasets.

- Provision of supporting documentation that describes the operational algorithms employed in dataset generation, outlines the results of quality assessments, and a user guide to assist users in the appropriate utilisation of the datasets.

- Maintenance of metadata describing CDR datasets and their associated documentation.

- Provision of user support services.

- Contribution to the European State of the Climate, contingent upon the maturity and latency of the ECV data, or an alternative form of support for climate intelligence.