ISEA Special Issue European Geosciences Union Short-period
gravity waves of especially-small horizontal scale have been
observed in the Maui, Hawaii airglow. Typical small-scale
gravity wave events have been investigated, and intrinsic wave
propagation characteristics have been calculated from
simultaneous meteor radar wind measurements. Here we report
specific cases where wave structure is significantly determined
by the local wind structure, and where wave characteristics are
consistent with ducted or evanescent waves throughout the
mesopause region. Two of the documented events, exhibiting
similar airglow signatures but dramatically different
propagation conditions, are selected for simple numerical
modeling case studies. First, a Doppler-ducted wave trapped
within relatively weak wind flow is examined. Model results
confirm that the wave is propagating in the 85–95 km region,
trapped weakly by evanescence above and below. Second, an
evanescent wave in strong wind flow is examined. Model results
suggest an