Surface Net Solar Radiation Estimated from Satellite Measurements: Comparisons with Tower Observations

Abstract

A parameterization that relates the reflected solar flux at the top of the atmosphere to the net solar flux at the surface in terms of only the column water vapor amount and the solar zenith angle was tested against surface observations. Net surface fluxes deduced from coincidental collocated satellite-measured radiances and from measurements from towers in Boulder during summer and near Saskatoon in winter have mean differences of about 2 W m−2, regardless of whether the sky is clear or cloudy. Furthermore, comparisons between the net