06 January 1989
Vol 243, Issue 4887

About The Cover

Depiction of the effect of clouds on the radiative heating of the planet as determined from the NASA Earth Radiation Budget Experiment. Regions where clouds have a cooling effect are shown in green and blue (dark blue, strongest effect). The cooling effect arises because the reflection of solar radiation by clouds exceeds their greenhouse effect. In yellow regions the two effects nearly cancel; rust indicates slight heating. Globally, the satellite data revealed that clouds have a large cooling effect on the radiation budget of the planet. See page 57. [V. Ramanathan et al., Department of Geophysical Sciences, University of Chicago, Chicago, IL 60637; color images processed at NASA Langley Research Center, Hampton, VA 23665]