ABSTRACT

Due to a possible decrease of the total ozone abundance - which is expected to lead to an increase in harmful UV Radiation - the measurement of UV Radiation reaching the surface has become to an important part of climatic observations. So we are interested in possible long-term trends in UV doses related to health and environmental issues.

Further factors controlling the amount of UV-radiation on the surface are the solar elevation, cloud cover and ground reflection (single scattering albedo). Therefore, direct UV irradiance measurements, in combination with a radiative transfer model, allow determination of biologically effective UV doses, albedo and cloud transmission. At UNIS (The University Courses on Svalbard) in Longyearbyen, we use a 5-channel UV irradiance measurement instrument (NILU-UV), combined with a continuously measuring spectrometer. The measurement site in Longyearbyen could be of a special interest because of its high latitude in a polar region (78.2 deg N) and could become an important part in the observations of the middle polar atmosphere.

Examples: "Determination of an effective spectral surface albedo from ground based global and direct UV-irradiance measurements" (A.Kylling, T.Persen, B. Mayer, T.Svenoe),
http://www.nilu.no/avd/reg-glo/uv/publications/albedo.html
or "Effect of aerosols on solar UV irradiances during the photochemical activity and solar ultraviolet radiation campaign" (A.Kylling, A.F. Bais, M.Blumthaler, J.Schreder, C.S. Zerefos, E. Kosmidis),
http://www.nilu.no/avd/reg-glo/uv/publications/paur-irr.html