The monthly Outgoing Longwave Radiation (OLR) Climate Data Record (CDR) measures the amount of terrestrial radiation released into space, as well as the amount of cloud cover and water vapor that intercepts that radiation in the atmosphere. Input data for the monthly OLR record primarily comes from the high-resolution infrared radiation sounder (HIRS) radiance observations since 1979, and new generation infrared hyperspectral sounded radiance data, including from the Infrared Atmospheric Sounding Interferometer (IASI) since 2007 and the Cross-track Infrared Sounder (CrIS) since 2012. The final record was developed through a combination of statistical techniques, including OLR regression, instrument ambient temperature prediction coefficients, and inter-satellite bias corrections. This dataset spans from 1979 - present.