Cloud Attenuation Studies, Mount Washington, New Hampshire

Abstract : The objective of the work described was to obtain more reliable quantitative information than was available on the attenuation coefficient of clouds and to obtain the correlation between visual range and the attenuation coefficient. A cloud attenuation meter consisting of a source-detector unit, a reflector unit and a control-meter cabinet was used to make simultaneous observations of visual range and optical density. Values found for the coefficient, according to Lambert-Bouguet law, were between 1.4 and 5.9 per hundred feet.