Satellite-based surface solar radiation data records from the CM SAF – developing towards the new SARAH-4 climate data record

The incoming surface solar radiation is an essential climate variable as defined by GCOS. Long term monitoring of this part of the earth’s energy budget is required to gain insights on the state and variability of the climate system.

The EUMETSAT Satellite Application Facility on Climate Monitoring (CM SAF) generates and distributes high quality long-term climate data records (CDR) of energy and water cycle parameters, which are freely available.

The CLARA and SARAH data records will be extended and updated in their next releases. Especially the latter will become a quasi-global data record in its upcoming edition - SARAH-4. Data from five geostationary orbits will be processed, allowing the provision of global data (excluding the high latitudes) in high spatial (0.05°) and temporal (30 minutes) resolution. In addition, SARAH-4 will employ daily varying aerosol information from MERRA-2 (in contrast to climatological aerosol information used in SARAH-3). Finally, the successor of the METEOSAT SEVIRI instrument, FCI, will be used for a consistent near-realtime data processing for the METEOSAT-Prime orbit.

The presentation will give an overview of the status quo of CM SAF’s surface solar radiation data records and will give insights into the ongoing developments. The current status and the recent results of the upcoming SARAH-4 data records will be presented. The focus will be on the impact of the daily aerosol information on the surface solar radiation record, which leads to improvements in case of aerosol-loaded atmospheric conditions. Some general validation results of the intermediate SARAH-4 data records will be shown as well.