LIVAS: a 3-D multi-wavelength aerosol/cloud database based on CALIPSO and EARLINET

Abstract. We present LIVAS ( LIdarclimatology of Vertical AerosolStructure for space-based lidarsimulation studies), a 3-D multi-wavelength global aerosoland cloud optical database, optimized to be used for future space-based lidarend-to-end simulations of realistic atmospheric scenarios as well as retrieval algorithm testing activities. The LIVAS database provides averaged profiles of aerosoloptical properties for the potential spaceborne laser operating wavelengths of 355, 532, 1064, 1570 and 2050 nm and of cloud optical properties at the wavelength of 532 nm. The global database is based on CALIPSO observations at 532 and 1064 nm and on aerosol-type-dependent backscatter- and extinction-related Angstrom exponents, derived from EARLINET (European AerosolResearch LidarNetwork) ground-based measurements for the UV and scattering calculations for the IR wavelengths, using a combination of input data from AERONET, suitable aerosolmodels and recent literature. The required spectral conversions are calculated for each of the CALIPSO aerosoltypes and are applied to CALIPSO backscatter and extinction data corresponding to the aerosoltype retrieved by the CALIPSO aerosolclassification scheme. A cloud optical database based on CALIPSO measurements at 532 nm is also provided, neglecting wavelength conversion due to approximately neutral scattering behavior of clouds along the spectral range of LIVAS. Averages of particle linear depolarization ratioprofiles at 532 nm are provided as well. Finally, vertical distributions for a set of selected scenes of specific atmospheric phenomena (e.g., dust outbreaks, volcanic eruptions, wild fires, polar stratospheric clouds) are analyzed and spectrally converted so as to be used as case studies for spaceborne lidarperformance assessments. The final global data set includes 4-year (1 January 2008–31 December 2011) time-averaged CALIPSO (Cloud- Aerosol Lidarand Infrared PathfinderSatellite Observations) data on a uniform grid of 1° × 1° with the original high vertical resolution of CALIPSO in order to ensure realistic simulations of the atmospheric variability in lidarend-to-end simulations.