Aerosol optical-to-microphysical conversion factors for lidars and ceilometers from extended AERONET data analyses: POLIPHON update

Abstract

Updated POLIPHON (Polarization Lidar Photometer Networking) conversion factors for the laser wavelengths of 355, 532, 911, and 1064 nm are presented. The conversion factors allow us to transfer profiles of aerosol-type-dependent optical properties measured with lidars and ceilometers into profiles of microphysical particle properties, and to estimate cloud condensation nucleus (CCN) and ice-nucleating particle (INP) concentrations at observed cloud levels. These updates were necessary to permit a coherent and harmonized data analysis of different long-term spaceborne lidar observations at 355 and 532 nm and to support ground-based lidar and ceilometer network measurements and research on aerosol–cloud interaction. The POLIPHON conversion factors are obtained by analyzing long-term sun photometer observations conducted at 62 AERONET (Aerosol Robotic Network) stations. Conversion factors are now available for mineral dust, marine aerosol, urban and rural anthropogenic particles, tropospheric and stratospheric wildfire smoke and volcanic sulfate aerosol.