Atmospheric aerosol radiative effects

The effect of atmospheric aerosol properties on solar and infrarred radiation is crucial for climate model estimates, which are key for the development of strategic plans for climate change mitigation and for policymakers worldwide. Vertically-resolved aerosol properties obtained with remote sensors such as lidar systems are fundamental in this sense. At the Universitat Polit├Ęcnica de Catalunya, the optical remote sensing group routinely performs lidar measurements of aerosol vertical profiles, in combination with photometer measurements of the solar and sky radiation. The acquired data feed the radiative transfer model GAME (Global Atmospheric ModEl), developed at the University of Lille, in order to compute the aerosol 1-D radiative effect. Pyranometers and pyrgeometers, also operated by the group, provide continuous and direct radiation measurements and are used for the validation of GAME flux estimates, prior to the computation of the radiative effect.

Additionally, in collaboration with different research groups within EARLINET (European Aerosol Lidar Network) and taking advantage of satellite measurements such as those performed by CALIOP (Cloud-Aerosol Lidar with Orthogonal Polarization) instrument onboard CALIPSO (Clouds-Aerosol Lidar and Infrared Pathfinder Observations), the group has recently gained the capability to conduct detailed analysis of the aerosol 2-D radiative effects above the Mediterranean region.

Figure 1. CALIOP attenuated backscatter on 31 May 2013, during a dust event affecting Limassol EARLINET site (indicated by the red square).

Figure 2. (top) Mineral dust aerosol radiative forcing retrieved with GAME along CALIPSO track on 31 May 2013 (bottom) Aerosol optical depth at 550 nm and mineral dust forcing at the surface for the same track segment.