Specification of Cloud Amount over Local Areas from GOES Visual Imagery
Abstract
Albedos derived from GOES visual imagery data are compared with the cloud cover reported at seven sites in the northeastern United States in the spring through autumn of 1977 and 1978. The data sample was closely edited to remove all cases containing unexplainable inconsistencies between the satellite and surface data. Statistics were generated for the aggregate of stations for spring/summer and autumn periods separately, as well as the two years separately. The seasonal data were further divided into those cases that contained predominantly ice crystal clouds or water clouds. The characteristics of the satellite data were computed for a 9 by 9 one-mile pixel box and were the average, maximum and minimum albedos, the range of albedo, and the texture. Detailed attention was given to the relationship between average albedo and cloud amounts. Equations were generated for each station for each year for the water droplet clouds during the spring/summer season. There were not sufficient cases to do the same for the autumn of the ice crystal cloud cases. There is a logical, consistent variation in the equations from station to station despite noisy data and a serious shortage of data throughout most of the scattered and broken cloud cover ranges. A multivariate analysis including infrared characteristics is indicated. (Author)
Document Details
- Document Type
- Technical Report
- Publication Date
- May 28, 1981
- Accession Number
- ADA109325
Entities
People
- Michael Niedzielski
- Thomas J. Keegan
Organizations
- Air Force Research Laboratory