Because of the importance of radiation in weather and climate, the Clouds and the Earth's Radiant Energy System (CERES) program flew radiation budget instruments on the Tropical Rainfall Measuring Mission (TRMM) and the TERRA and AQUA spacecraft. Also, the Surface Radiation Budget program has developed an 8-year set of surface radiation fluxes based on satellite data. This paper examines maps of outgoing longwave radiation fluxes and net radiation fluxes over Africa and their relations to the climate processes. Plots of radiative flux as a function of latitude and time for a given longitude show movements of the monsoons with season and also their intraseasonal variations. At 20 degrees east, the net radiative flux in the convection region is 90 W/m**2 and greater. This surplus of radiation provides the energy required to maintain the convection. In the dry region it is -30W/m**2 or more. This deficit of radiation comes from the conversion of potential energy as the air subsides in these regions. In January, the convection is centered at 15 degrees S (the Congo Basin), and moves just north of the Equator in July, where the lack of water vapor causes the convection to weaken. The convection increases to cover a broad region (20 degrees of latitude) with its return south.
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