CAL_LID_L3_Tropospheric_APro_AllSky-Standard-V5-00 is the Cloud-Aerosol Lidar and Infrared Pathfinder Satellite Observation (CALIPSO) Lidar Level 3 Tropospheric Aerosol, All-Sky, data product. This data product was collected using the Cloud-Aerosol Lidar with Orthogonal Polarization (CALIOP) instrument. This data product, generated separately between day and night, reports monthly mean profiles of aerosol optical properties on a uniform spatial grid. It is a tropospheric product, so data are only reported below altitudes of 12 km. All parameters are derived from the version 5.00 CALIOP Level 2 data and have been quality screened prior to averaging. The primary quantities reported are vertical profiles of the aerosol extinction coefficient at 532 nm and its vertical integral, the aerosol optical depth (AOD). Aerosol type and spatial distributional information are also included. The All-Sky designate indicates that all level 2 columns are averaged, regardless of the occurrence of clouds.

CALIPSO was a partnership between NASA and the French Space Agency, CNES. CALIPSO was launched on April 28, 2006 to study the many roles played by clouds and aerosols 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 its orbit from 705 km to 688 km (428 miles) above the Earth to resume formation flying with CloudSat as part of the “C-Train”. The CALIPSO satellite carried three remote sensing instruments: the Cloud-Aerosol Lidar with Orthogonal Polarization (CALIOP), the Imaging Infrared 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.