Automated Measurements of Atmospheric Visibility

Abstract

The concept of using a solid-state, linear-array imaging device coupled with computerized scene analysis and display to measure daytime atmospheric visibility is described. Computer software is implemented for routine conversion of observed target and sky radiances into measurements of horizon contrast, visual range, target color impairment, and target modulation depth, i.e., target texture and clarity. An assembled, working instrument has been applied to field measurements. Several examples of field measurements are presented. The instrument is fully automated, and is available for visibility research; its applicability to routine visibility monitoring and as an operational tool for aircraft operations is explored.