Effect of ambient temperature on Robertson-Berger-type erythemal dosimeters
Huber, M., M. Blumthaler, J. Schreder, A. Bais, C. Topaloglou
[περίληψη] To quantify the effect of ambient temperature on the voltage signal of Solar Light Biometers, spectral response functions of two instruments have been determined in the laboratory under varying external temperature conditions. Despite the Biometers internal temperature stabilization, a temperature increase at the outside of the instruments housing by 20°C results in a reduction of the instruments spectral response by up to 10% in the UVB range and by up to a factor of 2 in the UVA range, depending on the individual instrument and on its internal humidity status. Significance of this effect for outdoor measurements is demonstrated by data from the LAP/COST/WMO Intercomparison of Erythemal Radiometers on Sept., 16, 1999 in Thessaloniki (Greece), when 12 out of 16 Solar Light Biometers have shown significant diurnal variation in their sensitivity by up to 10% for some individual instruments.