CALIPSO Total Attenuated Backscatter
The CALIPSO lidar level 1.5 data product contains profiles of attenuated backscatter and aerosol extinction coefficients for which clouds, overcast, surface, subsurface, and totally attenuated samples have been removed before being averaged to a 20 km horizontal resolution. This product is a synthesis of CALIPSO lidar level 1B and lidar level 2 aerosol profile products with the lidar level 2 vertical feature mask used for feature identification and screening. Thus, it is deemed a “level 1.5” product.
The lower panel of the image demonstrates that level 1.5 cloud-cleared attenuated backscatter is comprised solely of molecular and aerosol scattering. The level 1.5 data product is generated using two production strategies: standard and expedited. The standard production strategy uses the most recent CALIOP version 4 data as input, thus providing accurately calibrated attenuated backscatter and the benefits of the most sophisticated CALIOP scene classification algorithms.