A two-dimensional photochemical model based on diabatic circulation has been used to simulate the behavior of N2O, CFCl3(F-11), and CF2Cl2(F-12). The circulation is based on estimates of net heating from the ground to 60 km. Eddy diffusion has been reduced with respect to other model studies with Kzz=2¿103 cm2s-1 everywhere above 100 mbar. Resulting tracer profiles show reasonable agreement with measured profiles in the tropics and fall off much more sharply with altitude than those produced by models using larger values of Kzz. The agreement obtained is at least as good as that obtained with adjustable, eddy diffusion parameters. The diabatic circulation treatment is more closely related to real physical processes and thus more easily interpreted. Diffusive mixing appears to be more important in determining the details of the tracer distribution than the basic morphology.