SARAH-3 – satellite-based climate data records of surface solar radiation

The amount of energy reaching the Earth’s surface from the sun is a quantity of high importance for the climate system and for renewable energy applications. SARAH-3 is a new edition of a satellite-based climate data record of surface solar radiation parameters. It is generated and distributed by the European Organisation of Meteorological Satellites (EUMETSAT) Satellite Application Facility on Climate Monitoring (CM SAF). SARAH-3 covers more than 4 decades of data and provides a high spatial resolution of 0.05° x 0.05° and a temporal resolution of 30-minutes, daily means and monthly means. SARAH-3 consists of seven parameters including surface irradiance, direct irradiance and sunshine duration. SARAH-3 is the successor of SARAH-2.1 and is accompanied by an operational near-real time processing of all parameters – the so-called Interim Climate Data Record, enabling climate monitoring applications. The validation of SARAH-3 shows a good accuracy and stability of the data record and further improves over its predecessor. One reason for this improvement is the new treatment of snow-covered surfaces in the algorithm, reducing the misclassification of snow as clouds. The SARAH-3 climate analysis reveals an increase of the surface irradiance during the last decades in Europe.