Variability of cloud-free ultraviolet dose rates on global scale due to modeled scenarios of future ozone recovery.

Simulations of the total ozone content and vertical ozone and temperature profiles during the period 1980-2080 from three chemistry climate models (CCMs) were used and the future variability of five UV dose rate types in global scale was simulated. For each CCM, radiative transfer calculations for cloud-free skies and constant values of aerosol optical properties and surface reflectivity were performed and the percentage difference, relative to the mean over the period 1996-2005, was calculated. The potential biological consequences of ozone recovery are quantified due to the different influence of ozone-absorbing wavelengths on the selected UV action spectra: average percentage differences between a few and 60% are revealed during the 2070s, depending on the latitude zone and the season. Although the research into the prediction of UV radiation levels is ongoing, due to the possible future changes in cloudiness, aerosols or surface reflectivity, the long-term changes in ozone, as projected by the CCMs in a similar way, will affect strongly some of the selected UV dose rates in the future.