  The condition of internal gravity waves (IGW) parametric excitation in the
rotating fluid layer heated from above, with the layer vibration along the
vertical axis or with periodic modulation in time of the vertical temperature
distribution, is obtained. We show the dual role of the molecular dissipative
effects that may lead not only to the wave oscillations damping, but also to
emergence of hydrodynamic dissipative instability (DI) in some frequency band
of IGW. This DI also may take place for the localized in horizontal plane
tornado-like disturbances, horizontal scale of which does not exceed the
character vertical scale for the fluid layer of the finite depth. Investigated
parametric resonance mechanism of IGW generation in ocean and atmosphere during
and before earthquakes allows monitoring of such waves (with double period with
respect to the period of vibration or temperature gradient modulation) as
precursors of these devastating phenomena.
