The energy budget of the earth–atmosphere system in Europe

Vertically integrated divergences of time mean atmospheric energy fluxes are computed for various subareas of Europe using radiosonde data from 1974–1976, and are used, together with relevant information in the literature, to discuss the energy budget of the earth-atmosphere system for these areas. It is found that a reasonable budget can be obtained when the size of the area is not smaller than 6–7 106 km2.

Considering the mainland of Europe, the convergence of the atmospheric total energy flux amounts to 55 ± 15 W/m2 annually, which is comparable to satellite-based estimates of the net radiation flux, -35 to -70 W/m2, for the same region. This convergence is about twice as large as the corresponding zonally averaged convergence in the corresponding latitude belt.

In the atmosphere, the combined mean-flow flux of sensible heat and potential energy is found to be the most important factor in the energy budget. However, the role of the transient eddies is also important, particularly in the convergence of latent heat and kinetic energy. The transient eddy flux divergences of total energy in winter act so as to dissipate the longitudinal anomalies of total energy.