The study and monitoring of radiative transfer processes taking place in the atmosphere turns out to be essential in order to understand important mechanisms ruling Earth's climatic system.

Variable atmospheric constituents like aerosols, trace gases and clouds have a large role in determine radiation balance and modulating short-wave and long-wave terms at the surface (Bottom Of Atmosphere - BOA) as well as at the Top Of the Atmosphere (TOA). These direct effects on radiation fluxes at BOA and TOA can be relevant at local, regional and global scale. Reflectance characteristics of the Earth surface can largely influence these processes mainly in polar regions, where high values of surface albedo occur for the most part of the year. Than, they need to be accounted for with accuracy when radiative transfer code are used to determine effects of changes on the climate system.

Interest of our group is devoted to investigate processes above described in polar areas as well as in the Mediterranean region. Measurements as well as radiative transfer code suitably modified and constrained by experimental results are used to deepen our knowledge on radiative processes, role played by aerosols, clouds, trace gases and surface characteristics, and forcing on the Earth's climatic system arising at local and regional scale by changes in concentration, distribution and physico-chemical characteristics of these atmospheric constituents.

Main experimental activities are characterization of aerosol population in the vertical column, making use of both passive remote sensing techniques (sun and sky photometers) and in-situ instruments, accurate measurement of radiation fluxes at the surface and evaluation of the radiation balance, measurement of surface reflectance characteristics (albedo), measurements of UV fluxes and evaluations of relevant quantity for biological organisms. These activities are routinely carry out at Italian stations in Antarctica and in the Arctic, as well as at Bologna and at a near rural site of the Po Valley.

Modeling activities include evaluations of direct effects of aerosols on radiation budget at the BOA, TOA and into the atmosphere at local scale as well on a regional scale (using satellites data), study of effects introduced by Bi-Directional Reflectance Surface characteristics (BDRF), closure experiments between evaluations and measurements, study of role of different atmospheric conditions on UV fluxes at the surface and possible biological effects of UV radiation.