This paper describes the All Sky Infrared Visible Analyzer (ASIVA), amulti-purpose visible and infrared sky imaging and analysis instrument whoseprimary function is to provide radiometrically calibrated imagery in themid-infrared (mid-IR) atmospheric window. This functionality enables thedetermination of diurnal fractional sky cover and estimates of sky/cloudtemperature from which one can derive estimates of sky/cloud emissivity andcloud height. This paper describes the calibration methods and performanceof the ASIVA instrument with particular emphasis on data products beingdeveloped for the meteorological community. Data presented here werecollected during the Solmirus' ASIVAcampaign conducted at the Atmospheric Radiation Measurement (ARM) SouthernGreat Plains (SGP) Climate Research Facility from 21 May to 27 July 2009.The purpose of this campaign was to determine the efficacy of IR technologyin providing reliable nighttime sky cover data. Significant progress hasbeen made in the analysis of the campaign data over the past several yearsand the ASIVA has proven to be an excellent instrument for determining skycover as well as the potential for determining sky/cloud temperature,sky/cloud emissivity, precipitable water vapor (PWV), and ultimately cloudheight.
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