CAL_IIR_L1-Standard-V3-00 data are Cloud-Aerosol Lidar and Infrared Pathfinder Satellite Observations (CALIPSO) Infrared ImagingRadiometer (IIR) Level 1B radiance data. The IIR Level 1B data product contains a half orbit of geolocated, calibrated radiances. Earth view images are registered to a 1 km grid centered on the lidar track. CALIPSO was a partnership between NASA and the French Space Agency, CNES.CALIPSO was launched on April 28, 2006, to study the many roles clouds and aerosols play in Earth’s climate and weather. It flew in the international A-Train constellation for coincident Earth observations from launch until September 13, 2018, when CALIPSO began lowering itsorbit from 705 km to 688 km (428 miles) above the Earth to resume formation flying withCloudSat as part of the “C-Train”. The CALIPSO satellite carried three remote sensing instruments: the Cloud-Aerosol Lidar with Orthogonal Polarization (CALIOP), the ImagingInfrared Radiometer (IIR), and the Wide Field-of-View Camera (WFC). By mutual agreement between NASA and CNES, the CALIPSO science mission concluded on August 1, 2023.