UV radiation below an Arctic vortex with severe ozone depletion B. M. Knudsen1, H. Jønch-Sørensen1, P. Eriksen1, B. J. Johnsen2, and G. E. Bodeker3 1Danish Meteorological Institute, Copenhagen, Denmark 2Norwegian Radiation Protection Authority, Oslo, Norway 3National Institute of Water and Atmospheric Research, Lauder, New Zealand
Abstract. The erythemally weighted (UV) irradiance below the severely depleted Arctic
vortices in spring 1996 and 1997 were substantially elevated. On average the
UV increased 36 and 33% relative to the 1979-1981 mean assuming clear
skies from day 80-100 in 1996 and 1997, respectively. On clear sky days
large regions of the Arctic experienced maximum UV increases exceeding 70
and 50% on single days in 1996 and 1997, respectively. A minor fraction
of these increases are not anthropogenic and have a dynamical origin as seen
by comparison to 1982, when hardly any ozone depletion is expected.
Citation: Knudsen, B. M., Jønch-Sørensen, H., Eriksen, P., Johnsen, B. J., and Bodeker, G. E.: UV radiation below an Arctic vortex with severe ozone depletion, Atmos. Chem. Phys., 5, 2981-2987, doi:10.5194/acp-5-2981-2005, 2005.