An Integrated Surface Radiation Measurement System

Abstract

Abstract An integrated surface radiation measurement system has been developed to measure the surface radiation exchange flux. The system employs upward- and downward-looking Eppley pyrgeometers and pyranometers to separately measure four components: downwelling and upwelling, as well as short- and longwave atmospheric radiation. Additional thermisters, installed by Eppley Laboratories, give a more accurate measurement of dome temperature, and the analog battery-powered thermopile temperature compensation circuit is replaced with a voltage-standard circuit. This circuit also serves to produce accurate thermisters excitation. All the parameters of the pyrgeometers, including the output of the thermopile, the temperature of the upper surface of thermopile, and the dome and the case temperatures, are monitored directly. This allows corrections to be made for the thermal emission of the thermopile and a realistic Stefan–Boltzmann calculation to correct for the solar heating of the pyrgeometer dome. The signal...