LSA SAF Land Surface Temperature: Evolution and Validation of Version 2 suite of Products

Abstract. The main objective of the Satellite Application Facility on Land Surface Analysis (LSA-SAF) is to provide Earth Observation data to support land, land–atmosphere and biosphere applications, with commitments to maintain operational near-real time products that are consistent with corresponding Climate Data Records (CDR) produced offline. The LSA-SAF has been providing estimates of Land Surface Temperature (LST) for over two decades, based on observations from EUMETSAT satellites. This article describes the new developments introduced in the generation of LST from EUMETSAT satellites by the LSA-SAF. The so-called version 2 suite of products includes LST from SEVIRI on-board the MSG series, for both the 0-degree (MLSTv2) and IODC (IODC MLSTv2) coverage, and from AVHRR on-board Metop satellites (EDLSTv2). It also includes an all-sky product (MLST-ASv2) that combines clear-sky LST from MLSTv2 with cloudy skin temperature from a surface energy balance model developed within the LSA-SAF (METv3). The main algorithm developments with respect to the older operational version include a revision of the calibration database used to train the LST retrieval algorithm and of the land surface emissivity algorithm. The sensors calibration was also revised to solve discontinuity issues. The overall accuracy of the LSA-SAF datasets, when compared to in-situ data, is 0.20 K, 0.21 K, -0.22 K and 0.24 K for MLSTv2, IODC MLSTv2, EDLSTv2 and MLST-ASv2, respectively. The LSA-SAF also aims to provide LST datasets that meet the GCOS requirements for climate applications. Analyses of the products’ stability shows that all datasets meet the GCOS requirements, with exception of the IODC MLSTv2. The LST algorithms presented here have also been adapted and implemented for the generation of LST from the new Meteosat Thrid Generation (MTG) and Metop Second Generation (Metop-SG), ensuring continuity of the Meteosat and Metop services. Monthly averages from each product for the respective data record period on a 0.25^ox0.25^o regular grid are available from https://doi.org/10.5281/zenodo.20705177 (Ermida et al., 2026). The full resolution data is available from the LSA-SAF data server at https://datalsasaf.lsasvcs.ipma.pt/.