Abstract: The concept of a mechanistic general circulation model that explicitly simulates the gravity wave drag in the extratropical upper mesosphere in a self-consistent fashion is proposed. The methodology consists of 1) a standard ...

Abstract: In climate and weather forecast models, small-scale turbulence in the free atmosphere is usually parameterized by horizontal diffusion of horizontal momentum. This study proposes a formulation that is based on a symmetric ...

Abstract: his study addresses the heat budget of the mesosphere and lower thermosphere with regard to the energy deposition of upward propagating waves. To this end we recapitulate the ener-getics of gravity waves, using an anelastic ...

Abstract: A new finite-difference formulation of the frictional heating associated with atmospheric vertical momentum diffusion is proposed. It is derived from the requirement that, according to the no-slip condition, the sum of ...

Abstract: An attempt is made to define the thermodynamics of internal gravity waves breaking in the middle atmosphere on the basis of the energy conservation law for finite fluid volumes. Consistent with established turbulence theory, ...

Abstract: he horizontal kinetic energy spectrum and its budget are analyzed on the basis of a general circulation model with simplistic parameterizations of radiative and latent heating. A spectral truncation at total wavenumber 330 ...

Abstract: The diffusion?dissipation parameterizations usually adopted in GCMs are not physically consistent. Horizontal momentum diffusion, applied in the form of a hyperdiffusion, does not conserve angular momentum and the associated ...

Abstract: The mixing-length-based parameterization of horizontal diffusion, which was originally proposed by Smagorinsky, is revisited. The complete tendencies of horizontal momentum diffusion, the associated frictional heating, and ...

Abstract: On the basis of permanent January simulations performed with an idealized general circulation model for the troposphere and middle atmosphere, the sensibility of the general circulation to orographic and thermal forcing ...