Variability of Earth-Emitted Radiation from One Year of Nimbus-6 ERB Data

Abstract

Outgoing longwave radiation (OLR) measurements from the Nimbus-6 ERR wide field-of-view (WFOV) instrument are used to study daytime and nighttime radiation variability on a 15° regional, zonal and global scale. An analysis of components of variance is used to determine how much of the total variability is due to between-region and within-region variance. Most of the analysis is on July and January data from one yr of Nimbus-6 ERB. Different geographical scales are considered: regions within latitude zones and latitude zones within hemispheres. Results show that much of the variability is spatial, peaks in the tropics and subtropics, and is concentrated in the Northern Hemisphere. Daytime variability is generally larger than nighttime variability for July but not for January. Variance in OLR in the tropics and subtropics is largely a function of cloud variability.