Increase in yearly ultraviolet radiation The % increase from 1980 to 1997 in erythemal UV radiation (causing the skin to turn red) is calculated using observed total ozone values from the TOMS satellite instruments and assuming clear sky conditions. Environment in the European Union at the turn of the century, European Environment Agency, Chapter 3.2. Ozone-depleting substances http://reports.eea.eu.int/C3S2I92-9157-202-0/en

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