A 42-year global sea surface temperature (SST) climate data record (CDR) from 1980 to 2021 has been produced using satellite observations, with minimal reliance on in situ measurements. The data include SSTs from 22 satellite platforms, with 1.4 × 10¹² suitable SST observations. The data are provided at a 0.05° latitude-longitude grid and include quality levels, standard uncertainties, and time-depth adjusted SSTs. The dataset improves accuracy, spatial coverage, and record length compared to previous versions. It includes satellite-based SSTs, time-depth standardised estimates, uncertainties, and quality flags. The data are processed using physically based methods to minimize dependence on in situ measurements. The CDR includes adjustments for time of day and depth to avoid aliasing the diurnal cycle into long-term trends. The dataset includes SSTs from infrared and microwave sensors, with adjustments for cloud cover, land, and ice. The data are available at four processing levels: Level 2 (single-sensor data), Level 3 (gridded data), Level 4 (daily gap-filled analysis), and Level 3 collated (daily data). The data are archived at CEDA and available through the ESA Open Data Portal under a Creative Commons license. The dataset is used for climate applications, including climate change quantification, model evaluation, and oceanography. The data include adjustments for depth and time to provide SST estimates at 20 cm depth and 10:30 or 22:30 local time. The dataset includes quality levels, uncertainty estimates, and adjustments for cloud cover, land, and ice. The data are used for climate applications, including climate change quantification, model evaluation, and oceanography. The dataset includes adjustments for depth and time to provide SST estimates at 20 cm depth and 10:30 or 22:30 local time. The dataset is available at four processing levels: Level 2 (single-sensor data), Level 3 (gridded data), Level 4 (daily gap-filled analysis), and Level 3 collated (daily data). The data are archived at CEDA and available through the ESA Open Data Portal under a Creative Commons license.A 42-year global sea surface temperature (SST) climate data record (CDR) from 1980 to 2021 has been produced using satellite observations, with minimal reliance on in situ measurements. The data include SSTs from 22 satellite platforms, with 1.4 × 10¹² suitable SST observations. The data are provided at a 0.05° latitude-longitude grid and include quality levels, standard uncertainties, and time-depth adjusted SSTs. The dataset improves accuracy, spatial coverage, and record length compared to previous versions. It includes satellite-based SSTs, time-depth standardised estimates, uncertainties, and quality flags. The data are processed using physically based methods to minimize dependence on in situ measurements. The CDR includes adjustments for time of day and depth to avoid aliasing the diurnal cycle into long-term trends. The dataset includes SSTs from infrared and microwave sensors, with adjustments for cloud cover, land, and ice. The data are available at four processing levels: Level 2 (single-sensor data), Level 3 (gridded data), Level 4 (daily gap-filled analysis), and Level 3 collated (daily data). The data are archived at CEDA and available through the ESA Open Data Portal under a Creative Commons license. The dataset is used for climate applications, including climate change quantification, model evaluation, and oceanography. The data include adjustments for depth and time to provide SST estimates at 20 cm depth and 10:30 or 22:30 local time. The dataset includes quality levels, uncertainty estimates, and adjustments for cloud cover, land, and ice. The data are used for climate applications, including climate change quantification, model evaluation, and oceanography. The dataset includes adjustments for depth and time to provide SST estimates at 20 cm depth and 10:30 or 22:30 local time. The dataset is available at four processing levels: Level 2 (single-sensor data), Level 3 (gridded data), Level 4 (daily gap-filled analysis), and Level 3 collated (daily data). The data are archived at CEDA and available through the ESA Open Data Portal under a Creative Commons license.