A Simple Seasonal Climate Model and Its Response to Variations in the Orbital Parameters

Abstract

The energy balance models of the type first formulated by Budyko (1) and Sellers (2) are indeed very simple. They contain only one variable quantity, namely.the zonally averaged surface temperature, and all physical processes represented in the model have to be parameterized in terms of this temperature field. In order to improve the original simple models it seems natural to represent the temperature in the atmosphere by more than one horizontal field. This should make possible a more accurate treatment of the physical processes, like radiation and convection. Furthermore it should also make it possible to develop a more advanced parameterization of the important meridional and vertical heat transport connected with the general circulation of the atmosphere. Such more complex energy balance models have been formulated by Suarez and Held (3) and by Eliasen and Laursen (4). A variant of the model formulated by Eliasen and Laursen is described in the following and it is shown, that the model has a significant sensitivity to the changes of the distribution of solar radiation caused by variations in the orbital parameters.