The Long Term Data Record (LTDR) project generates and distributes a validated global land surface climate data record (CDR) from processing of the Advance Very High Resolution Radiometer (AVHRR) onboard NOAA’s Polar Orbiting Environmental Satellites (POES) between 1981 – 2021, and the European Space Agency’s (ESA) MetOp platform from 2012 to present, using a combination of mature and tested algorithms. The project creates the daily surface reflectance product as the fundamental climate data record (FCDR), and daily Normalized Differential Vegetation Index (NDVI) and Leaf Area Index/Fractional Photosynthetic Active Radiation (LAI/FPAR) as two thematic CDRs (TCDRs).