On the numerical evaluation of the energy conversion integral

Numerical results of the “αω-” and the “ν∙∇∅-formulation” of the atmospheric energy conversion integral, as derived from ECMWF-data, are presented and discussed. It is shown that even global integrals of either formulation are considerably different. If the integration area is restricted to hemispheres, the differences — though growing somewhat larger — are of similar magnitude. The results suggest that numerical evaluations of the baroclinic energy conversion process are still associated with a considerable degree of uncertainty.