The spectral nature of solar irradiance variability and its phase relationship to solar activity

Rather firm conclusions regarding the nature of short term solar variability have been reached on the basis of recent studies of continuous time series of solar irradiance measurements. The measurements have been conducted with the aid of satellite mounted cavity radiometers. The present paper provides an interim report on further analysis concerning the spectral nature of solar variation and its relationship to other indicators of solar variability. It is pointed out that the Nimbus 7-ERB mission was able to deliver rather precise and continuous measures of solar irradiance at a variety of spectral bands. Spectral variations observed in the Nimbus 7-ERB solar monitor measurements appear to correspond to a quasi-black body shift due to the appearance of large earth-facing sun spots.