The Calculation of Solar Radiation over Lake Ontario

Abstract

<p> Simultaneous solar radiation and meteorological observations were taken from an instrumented tower located in southwestern Lake Ontario. During the four month period of this study (July-November, 1969) it was found that short-term fluxes of incoming global radiation could be predicted with a standard error which was better than 0.05 cal cm^-2min^-1 under cloudless conditions. Under cloudy conditions the lowest standard of prediction error (0.14 cal cm^-2min^-1) was obtained using a model which takes into account cloud type transmission. Under cloudless conditions the Fresnel curve underpredicts the albedos observed for low zenith angles and overpredicts when the zenith angle is high. This is mostly due to a backscatter effect estimated to be between 1.5 to 2% and to the albedo of diffuse radiation which was confirmed to be 6.5 to 7%.</p>