An automatic all sky scanning radiometer

Abstract

A microcomputer controlled all sky scanning radiometer covering the short wave (0.3–3.0 μm) and long wave (3.0–80.0 μm) regions and using a pyroelectric detector has been constructed for continuous automatic measurement of sky radiance. Angular distributions of short, long, and total wave sky radiance are recorded and plotted at each solar hour angle from which irradiances of tilted surfaces are computer calculated. Measurement of the local earth surface radiance facilitates estimation of short wave earth surface albedo and net income of radiation to variously oriented black surfaces. Total scanning, computation, and plotting time for each hour angle observation is 8 min.