UV irradiance and the risk of skin cancer in the Arctic

摘要

Abstract: Solar irradiance in the spectral region 280 to 400 (800) nm was measured with a double monochromator at two Arctic locations, Tromso (70$DGR@N) and Longyearbyen (78$DGR@N). During the observational (midnight sun) period in Longyearbyen, the maximum UVB irradiance recorded was less than 0.3 W/m$+2$/, and no radiation was detected for wavelengths below 300 nm. Such low levels are believed to be a consequence of the low solar elevation angle and the high ozone content of the Arctic ozone layer, which absorbs the incident UV light. With ozone levels between 280 and 350 DU over the period of study, Tromso and Longyearbyen recorded only one-ninth of the calculated UVB radiation at the equator. Malignant melanoma of the skin is three times higher in Oslo than in the northernmost parts of Norway and the rate of skin cancer is 7-8 times higher in the white population of equatorial countries than in Arctic regions. The low UVB radiation combined with a high protective ozone shield in the Arctic means people are at little risk from sun induced skin damage and development of skin cancer in this region. !12