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Title: A case study of a ducted gravity wave event over northern Germany using simultaneous airglow imaging and wind-field observations
Abstract. An intriguing and rare gravity wave event was recorded on the night of 25 April 2017 using a multiwavelength all-sky airglow imager over northernGermany. The airglow imaging observations at multiple altitudes in themesosphere and lower thermosphere region reveal that a prominent upward-propagating wave structure appeared in O(1S) and O2 airglowimages. However, the same wave structure was observed to be very faint in OH airglow images, despite OH being usually one of the brightest airglowemissions. In order to investigate this rare phenomenon, the altitudeprofile of the vertical wavenumber was derived based on colocated meteorradar wind-field and SABER temperature profiles close to the event location.The results indicate the presence of a thermal duct layer in the altituderange of 85–91 km in the southwest region of Kühlungsborn, Germany.Utilizing these instrumental data sets, we present evidence to show how aleaky duct layer partially inhibited the wave progression in the OH airglowemission layer. The coincidental appearance of this duct layer is responsible for the observed faint wave front in the OH airglow images compared O(1S) and O2 airglow images during the course of the night over northern Germany.  more » « less
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Annales Geophysicae
Medium: X
Sponsoring Org:
National Science Foundation
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