Cloud-Aerosol LIDAR and Infrared Pathfinder Satellite Observation (CALIPSO): Data Users Guide Browse Image Tutorial

This document describes the interpretation of CALIPSO’s standard suite of data product browse images for the three instruments on-board; Cloud Aerosol Lidar with Orthogonal Polarization (CALIOP), Imaging Infrared Radiometer (IIR), and Wide Field-of-View Camera (WFC).

CALIOP is an elastic backscatter lidar that emits pulsed laser light and measures the energies scattered directly back to the satellite from molecules and particulates (i.e. aerosols, clouds) in the atmosphere. CALIOP is a three-channel instrument operating at two wavelengths: 532 nm and 1064 nm. In the CALIOP receiver, the 532 nm backscatter is decomposed into polarization planes parallel (∥) and perpendicular (⊥) to the polarization plane of the transmitted laser light. Once the signals have been range-scaled, energy and gain normalized, geolocated and altitude registered, and calibrated, the measured backscatter from each detector.

IIR provides observations at 1-km resolution in three channels centered at 8.65, 10.6, and 12.05 μm. The swath is 69-km wide and is centered on the CALIOP track. Brightness temperatures reported in the Version 4 IIR Level 2 swath product are derived from the calibrated radiances reported in the Version 2 IIR Level 1 product using the relationships detailed in Garnier et al. (2018).

WFC is a narrow-band push-broom imager that provides continuous high spatial resolution (125m) images of radiance and reflectance during the daylight segments of a CALIPSO orbit over a 61 km swath centered on the lidar footprint. The spectral band of the WFC is designed to match the Aqua MODIS instrument channel 1 having a central wavelength of 645 nm and a bandwidth of 50 nm.