ESS228
Prof. Jin-Yi Yu
Internal Gravity Waves in Atmosphere and Oceans
q Internal gravity waves can be found in both
the statically
stable (dӨ/dz>0) atmosphere and the stably stratified (-dρ/dz>0)ocean.
qThe buoyancy frequency for the internal
gravity wave in the ocean is determined by the vertical density
gradient, while it is determined by the vertical gradient of potential temperature.
qIn the troposphere, the typical value of
N is 0.01 sec-1, which correspond
to a period of about 10 minutes.
qAlthough there are
plenty of gravity waves in the atmosphere, most of them have small amplitudes in the
troposphere and are not important, except that the gravity waves generated by flows
over mountains. These mountain waves can have large amplitudes.
qGravity waves become more important when
they propagate into the upper atmosphere (particularly in
the mesosphere) where their amplitudes got amplified due to low air density there.
In Atmosphere
In Oceans