Analyzing climate variability of surface solar radiation parameters from the CM SAF SARAH-3 climate data record

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 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 CM SAF SARAH-3 climate data record is based on satellite observations from the first and second METEOSAT generations and provides various surface radiation parameters, including global radiation, direct radiation, sunshine duration, photosynthetic active radiation and others. The SARAH-3 climate data records are accompanied by a corresponding near-realtime processing (so-called interim climate data records). With that, SARAH-3 covers the time period since 1983 with a timeliness of 1 day and offers 30-minute instantaneous data as well as daily and monthly means on a regular 0.05° x 0.05° lon/ lat grid. SARAH-3 enables a wide range of applications – from operational climate monitoring and model verification to renewable energy assessments.

The presentation will include validation and climate analysis of the SARAH-3 surface solar radiation parameters. A focus will be on the assessment of the temporal stability of the data record by comparison to alternative data records and surface reference measurements. Further, the climate variability and trends of the surface solar radiation will be analyzed. SARAH-3 reveals that there is a positive trend of surface solar radiation in Europe during the last decades, superimposed by decadal and regional variability. Also, potential causes for the found variability and trends (clouds, aerosols) will be discussed. Finally, an outlook on planned further developments will be given.