  We investigate the formation of hot coronae and vertical outflows in
accretion disks by magneto-rotational turbulence. We perform local
three-dimensional (3D) MHD simulations with the vertical stratification by
explicitly solving an energy equation with various effective ratios of specific
heats, gamma. Initially imposed weak vertical magnetic fields are effectively
amplified by magnetorotational instability (MRI) and winding due to the
differential rotation. In the isothermal case (gamma=1), the disk winds are
mainly driven by the Poynting flux associated with the MHD turbulence and show
quasi-periodic intermittency. On the other hand, in the non-isothermal cases
with gamma >~ 1.1, the regions above 1-2 scale heights from the midplane are
effectively heated up to form coronae with the temperature of ~ 50 times of the
initial value, which are connected to the cooler midplane region through the
pressure-balanced transition regions. As a result, the disk winds are mainly
driven by the gas pressure with exhibiting more time-steady nature, although
the nondimensional time-averaged mass loss rates are similar to that of the
isothermal case. Sound-like waves are confined in the cool midplane region in
these cases, and the amplitude of the density fluctuations is larger than that
of the isothermal case.
