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Abstract. Clouds warm the surface in the longwave (LW), and this warming effect can be quantified through the surface LW cloud radiativeeffect (CRE). The global surface LW CRE has been estimated over more than2 decades using space-based radiometers (2000–2021) and over the 5-year period ending in 2011 using the combination of radar, lidar and space-basedradiometers. Previous work comparing these two types of retrievals has shown that the radiometer-based cloud amount has some bias over icy surfaces. Here we propose new estimates of the global surface LW CRE from space-based lidarobservations over the 2008–2020 time period. We show from 1D atmosphericcolumn radiative transfer calculations that surface LW CRE linearly decreases with increasing cloud altitude. These computations allow us toestablish simple parameterizations between surface LW CRE and five cloud properties that are well observed by the Cloud-Aerosol Lidar and InfraredPathfinder Satellite Observations (CALIPSO) space-based lidar: opaque cloud cover and altitude and thin cloud cover, altitude, and emissivity. We evaluate this new surface LWCRE–LIDAR product by comparing it to existingsatellite-derived products globally on instantaneous collocated data atfootprint scale and on global averages as well as to ground-based observations at specific locations. This evaluation shows good correlationsbetween this new product and other datasets. Our estimate appears to be animprovement over others as it appropriately captures the annual variabilityof the surface LW CRE over bright polar surfaces and it provides a datasetmore than 13 years long.