Responses of the atmospheric circulation to a doubling of CO2 are examined in a global climate model, focusing on the circulation on both dry and moist isentropes. The isentropic circulations are reconstructed using the statistical transformed Eulerian mean (STEM), which approximates the isentropic flow from the Eulerian-mean and second-ordermoments. This approach alsomakes it possible to decom...

Isentropic mixing is an important process for the distribution of chemical constituents in the mid-to-high latitudes. A new framework is introduced to quantify both symmetric and asymmetric isentropic mixing in a modified Lagrangian coordinate. The framework is applied to quantify the mixing associated with the two types of Rossby wave breaking (i.e. cyclonic and anticyclonic) in two sets of id...

The near-surface branch of the overturning mass transport circulation in the troposphere, containing the equatorward flow, is examined in isentropic and geometric coordinates. A discussion of the zonal momentum balance within isentropic layers shows that the equatorward flow at a given latitude is confined to isentropic layers that typically intersect the surface at that latitude. As a conseque...

Onsager’s phenomenological equations successfully describe irreversible thermodynamic processes. They assume a symmetric coupling matrix between thermodynamic fluxes and forces. It is easily shown that the antisymmetric part of a coupling matrix does not contribute to dissipation. Therefore, entropy production is exclusively governed by the symmetric matrix even in the presence of antisymmetric...