Abstract
The global scale predictive tracer model designed to simulate atmospheric transport processes as well as a tropospheric and stratospheric chemistry is described. The model consists of a global spectral model and a set of the mass conservation equations coupled through the chemistry terms. The model was tested in both diagnostic and fully predictive mode simulating the hemispheric scale dispersion of radionuclides from the Chernobyl accident. The analysis of the predictive run results indicate that the model is able to predict the large scale mass distribution for periods up to six days when started from a sufficiently accurate initial condition. An extended prediction of the hemispheric tracer distribution was performed up to 24 days; the tracer field in these experiments was updated every 6 days using an initial condition provided by a parallel run of the diagnostic model.
