The hypothesis of minimum entropy production is applied to a simple one-dimensional energy balance model and is analyzed for different values of the radiative forcing due to greenhouse gases. The extremum principle is used to determine the planetary conductivity and to avoid the diffusive approximation, which is commonly assumed in this type of model. For present conditions the result at minimum radiative entropy production is similar to that obtained by applying the classical model. Other climate scenarios show visible differences, with better behavior for the extremal case. ¿ 1999 American Geophysical Union