AN INTERACTIVE CHEMICAL DYNAMIC RADIATIVE 2-DIMENSIONAL MODEL OF THE MIDDLE ATMOSPHERE

The distributions of chemically active species belonging to the oxygen, hydrogen, nitrogen and chlorine families are calculated for present-day conditions. By applying near the tropopause a different dynamical forcing in each hemisphere, the model produces significant hemispheric asymmetries in dynamical quantities (e.g., temperature) and trace gas densities (e.g., column ozone), in good agreement with climatological values. A major problem that remains to be elucidated is the underestimation by most models of the ozone density in the upper stratosphere. Because of the many feedback mechanisms included in its formulation, the model is well adapted to study the effects of human or natural perturbations. The response of the atmosphere to perturbations resulting from increasing emissions of CO2 and chlorofluorocarbons is considered. -from Authors