Measurements of surface and underwater UV radiation in Greenlandic waters and the response of phytoplankton production rates to UV exposure levels
Abstract
The impact of UV radiation on phytoplankton production was investigated during a measurement campaign in late May 2001 in the Disko Bay area on the westcoast of Greenland (lat. 69N, long. 53W). The surface UV irradiance was measured with a Robertson Berger type radiometer (Solar Light, Biometer) and a set of narrowband filterradiometers (Biospherical Instruments, PUV510). The underwater downwelling irradiance was measured with narrowband filter-radiometers (Biospherical Instruments, PUV500) from which the extinction coefficient (K_d) was deduced. Instruments were calibrated before the campaign started with a 1 kW spectral irradiance standard lamp. We will present surface and underwater UV measurements and the deduced extinction coefficients. From the surface measurements and the extinction coeffients deduced from the profiling the underwater irradiance was calculated and agreed well with the measured underwater irradiance. Analysis of exposed and unexposed phytoplankton shows inhibition of production at exposures above approximately 1000 J/m^2 (unweighted total UVB).
- Publication:
-
EGS - AGU - EUG Joint Assembly
- Pub Date:
- April 2003
- Bibcode:
- 2003EAEJA....14437E