Characteristics of the earth radiation budget experiment solar monitors

The earth radiation budget experiment solar monitors, active cavity pyrheliometers, have been developed to measure every two weeks the total optical solar irradiance from the earth radiation budget satellite (ERBS) and the National Oceanic and Atmospheric Administration NOAA-9 spacecraft platforms. In the unfiltered 0.2-50-microm wavelength broadband region, the monitors were used to obtain 1365 W/m(2) as the mean value for the solar irradiance with measurement precisions and accuracies approaching 0.1 and 0.2%, respectively. The design and characteristics of the solar monitors are presented along with the data reduction model. For the Oct. 1984 through July 1985 period, the resulting ERBS and NOAA-9 solar irradiance values are intercompared.