  We present the first dynamically and thermally self-consistent calculations
of fast adiabatically expanding gas flows from the Galactic disk into the halo.
It is shown that in a hot plasma (T >= 10^6 K) with a high overpressure with
respect to the ambient medium, the dynamical time scale is much shorter than
the intrinsic time scales (e.g. for recombination, collisional excitation and
ionization etc.). Therefore dynamical models that use collisional ionization
equilibrium (CIE) cooling functions for the evolution of the plasma are in
general not correct. In particular, the emission spectra obtained from
non-equilibrium calculations are radically different. We describe a method to
obtain self-consistent solutions using an iterative procedure. It is
demonstrated that soft X-ray background emission between 0.3 and 1.5 keV can be
well explained by a superposition of line emission and delayed recombination of
an initially hot plasma streaming away from the Galactic disk (outflow and/or
winds). In addition to these local winds we also present calculations on global
winds from spiral galaxies, which originate from a hot and quiescent galactic
corona. We also emphasize that it is dangerous to derive plasma temperatures
merely from line ratios of ionized species, such as NV/OVI, unless the
dynamical and thermal history of the plasma is known.
