Cloud Climatology Derived from the AFGWC (Air Force Global Weather Central) 3D-Nephanalysis for January and July 1979.
Abstract
Cloud climatologies of the Northern Hemisphere have been developed utilizing the AFGWC 3D-Nephanalysis (3DNEPH) cloud data base for January and July 1979. The vertical resolution of the 3DNEPH was reduced from 15 layers to 3 low, middle, and high (LMH) cloud layers. The horizontal grid points were mapped to the Nimbus-7 ERB/STA LAT/LON grid system to facilitate data comparison. Valid analysis times (Greenwich) were converted to local times. Zonal average total cloudiness correlates well with observed large-scale features for both months. The 3DNEPH compares reasonably well with other climatologies in the zonal average case except near the poles in the wintertime hemisphere. In this region, the 3DNEPH analysis overestimates the amount of midlevel cloudiness. This is thought to be caused by a lack of surface observations in the polar region, which may result in the infrared cloud processor misinterpreting cold snow-covered surfaces as clouds. Hemispherical plots of LMH and total cloud fields on a monthly mean scale are also presented.
Document Details
- Document Type
- Technical Report
- Publication Date
- Jan 15, 1987
- Accession Number
- ADA183686
Entities
People
- George Koenig
- Kuo-nan Liou
- Michael K. Griffin
Organizations
- University of Utah