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Based
on a linear wave model, Nappo and Chimonas [1992]
compared the fluxes generated by
turbulent motions and by internal gravity waves which are
induced by gentle surface irregularities.
They suggested that terrain-generated gravity waves are common in
the stable PBL and that these waves can generate as much
Reynolds stress and surface drag as those
due to turbulent motions.
Detailed wave-turbulence interaction was described by Einaudi and
Finnigan [1993] using data from the Boulder Atmospheric Observatory;
they showed the
budgets of kinetic energy, heat flux, and variance of
wave motions, which
revealed buoyancy production of wave
energy, and the role of wave-turbulence interaction in maintaining a large
amplitude temperature wave and countergradient wave heat flux.
Having obtained similar results in earlier studies, they conclude that
such behavior is not uncommon in this regime.
U.S. National Report to IUGG, 1991-1994
Rev. Geophys. Vol. 33
Suppl., © 1995 American Geophysical Union