The Copernicus Climate Change Service (C3S) contribution to Earth Observation Activities.

The Copernicus Climate Change Service (C3S) of the European Commission combinesobservations of the Earth System with state-of-the-art science to develop and make availableauthoritative and quality-assured data about the past, present and future climate, both inEurope and worldwide. The portfolio of service products includes the generation of ClimateData Records (CDRs) of Essential Climate Variables (ECVs) based on Earth Observation(EO) sensors and in-situ observations, reprocessing of Fundamental CDRs and data rescueactivities. Monitoring ECVs over long-term periods covering a minimum of several decades iscrucial, as they provide empirical evidence needed to understand the evolution of climate.C3S is currently producing global gridded CDRs of 22 ECVs divided in five themes:atmospheric physics, atmospheric composition, ocean, land hydrology and cryosphere andland biosphere. Several expert European consortia use advance methods to generate timely,consistent CDRs of ECVs with the satellite data record. Methodologies includeinter-sensor calibration, data harmonization and bias correction. This view of climateby remote observations is complemented with the generation of gridded CDRs ofECVs for the European domain, from 1950, based on surface in-situ data. Theseactivities support the work of international bodies such as the UNFCCC and theIPCC. Another activity for climate monitoring based on EO data is the comprehensivereprocessing of satellite data records from the satellite era (1979-). They can be used withclimate models or reanalysis to accurately describe the climate of the past. C3S supportsactivities encompassing the reprocessing of infrared and microwave sounding radiances;radio occultation and scatterometer data, as well as geostationary radiances and atmosphericmotion vectors derived from GEO and LEO satellites. In addition, C3S is engaged in therescue, assessment and characterisation of new data from the early satellite era (dating backto the late 1960s). This presentation will provide an overview and current status of the above activities, aswell as the main methodologies used in the service. [ABSTRACT FROM AUTHOR]