EUMETSAT's contribution towards producing climate quality reanalyses

Climate change is currently one of the main threats our planet is facing. Observations are playing a pivotal role in underpinning the science to understand the climate system and monitor its changes including extreme events, which have adverse effects on human lives. Information generated from measurements by Earth observation satellites contribute significantly to the development of this understanding and to the continuous monitoring of ongoing climate change and its impacts. However, the meaningful use of data from these satellites requires them to be long-term, spatially and temporally homogeneous, and uncertainty characterised. The process of preparing satellite data for climate studies is tedious and only recently being recognised as fundamental first step in preparing records of Essential Climate Variables (ECV) from these data.

EUMETSAT has generated several fundamental climate data records (FCDR) consisting of measurements from instruments operating from microwave to visible frequencies. These measurements are not only from EUMETSAT’s own satellite but also from satellites operated by other agencies such as NOAA, NASA, and JMA. This presentation outlines the basic principles of FCDR generation illustrated through a few examples. Basic steps of the FCDR generation is comprised of quality control of the raw data, recalibration of the raw data to produce physical quantities, such as radiances or reflectance, generate quality indicators, and create the outputs in user-friendly formats, e.g., NetCDF4. Furthermore, harmonisation of a suit of instruments are performed. The presentation will further domonstrate how the assimilation of these data records improve the quality of ERA6, the upcoming version of the European Reanalysis.