Characterization of exceptionally strong mesospheric wave events using all-sky and zenith airglow observations
Two unusually clear mesospheric gravity wave events were observed by the Boston University all-sky imager and the Argentine airglow spectrometer on two consecutive nights at the El Leoncito Observatory, Argentina (31.8°S, 69.3°W), during August 2001. Both events exhibited brightness amplitudes an or...
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todo:paper_21699402_v111_n9_p_Smith2023-10-03T16:40:07Z Characterization of exceptionally strong mesospheric wave events using all-sky and zenith airglow observations Smith, S.M. Scheer, J. Reisin, E.R. Baumgardner, J. Mendillo, M. Two unusually clear mesospheric gravity wave events were observed by the Boston University all-sky imager and the Argentine airglow spectrometer on two consecutive nights at the El Leoncito Observatory, Argentina (31.8°S, 69.3°W), during August 2001. Both events exhibited brightness amplitudes an order of magnitude above typical values. The first event had the appearance of a large-amplitude (>60% in OH(6-2), 22% in O 2 , and 37% in O( 1 S) emissions (peak to peak), compared to 1-5% typically), upward propagating gravity wave with pronounced nonlinear behavior. The waves also showed noticeably curved wavefronts, indicating that they had originated from a relatively small source region within ∼180 km of El Leoncito. Estimates of the vertical flux of horizontal energy and momentum for the wave event in the OH and O 2 emissions were very large compared to typical values, and they also indicated a high degree of flux divergence over the nominal 8 km altitude between the two layers. The second event occurred on the following night and exhibited a frontal morphology and behavior consistent with an internal ducted gravity wave showing nonlinear behavior akin to a mesospheric bore. The disturbance also had several interesting characteristics; in particular, the propagation speed decreased during its passage across the sky. In addition, a strong vertical temperature gradient due to the semidiurnal tide appeared to influence the occurrence of the bore event. Copyright 2006 by the American Geophysical Union. JOUR info:eu-repo/semantics/openAccess http://creativecommons.org/licenses/by/2.5/ar http://hdl.handle.net/20.500.12110/paper_21699402_v111_n9_p_Smith |
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Universidad de Buenos Aires |
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I-28 |
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R-134 |
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Biblioteca Digital - Facultad de Ciencias Exactas y Naturales (UBA) |
| description |
Two unusually clear mesospheric gravity wave events were observed by the Boston University all-sky imager and the Argentine airglow spectrometer on two consecutive nights at the El Leoncito Observatory, Argentina (31.8°S, 69.3°W), during August 2001. Both events exhibited brightness amplitudes an order of magnitude above typical values. The first event had the appearance of a large-amplitude (>60% in OH(6-2), 22% in O 2 , and 37% in O( 1 S) emissions (peak to peak), compared to 1-5% typically), upward propagating gravity wave with pronounced nonlinear behavior. The waves also showed noticeably curved wavefronts, indicating that they had originated from a relatively small source region within ∼180 km of El Leoncito. Estimates of the vertical flux of horizontal energy and momentum for the wave event in the OH and O 2 emissions were very large compared to typical values, and they also indicated a high degree of flux divergence over the nominal 8 km altitude between the two layers. The second event occurred on the following night and exhibited a frontal morphology and behavior consistent with an internal ducted gravity wave showing nonlinear behavior akin to a mesospheric bore. The disturbance also had several interesting characteristics; in particular, the propagation speed decreased during its passage across the sky. In addition, a strong vertical temperature gradient due to the semidiurnal tide appeared to influence the occurrence of the bore event. Copyright 2006 by the American Geophysical Union. |
| format |
JOUR |
| author |
Smith, S.M. Scheer, J. Reisin, E.R. Baumgardner, J. Mendillo, M. |
| spellingShingle |
Smith, S.M. Scheer, J. Reisin, E.R. Baumgardner, J. Mendillo, M. Characterization of exceptionally strong mesospheric wave events using all-sky and zenith airglow observations |
| author_facet |
Smith, S.M. Scheer, J. Reisin, E.R. Baumgardner, J. Mendillo, M. |
| author_sort |
Smith, S.M. |
| title |
Characterization of exceptionally strong mesospheric wave events using all-sky and zenith airglow observations |
| title_short |
Characterization of exceptionally strong mesospheric wave events using all-sky and zenith airglow observations |
| title_full |
Characterization of exceptionally strong mesospheric wave events using all-sky and zenith airglow observations |
| title_fullStr |
Characterization of exceptionally strong mesospheric wave events using all-sky and zenith airglow observations |
| title_full_unstemmed |
Characterization of exceptionally strong mesospheric wave events using all-sky and zenith airglow observations |
| title_sort |
characterization of exceptionally strong mesospheric wave events using all-sky and zenith airglow observations |
| url |
http://hdl.handle.net/20.500.12110/paper_21699402_v111_n9_p_Smith |
| work_keys_str_mv |
AT smithsm characterizationofexceptionallystrongmesosphericwaveeventsusingallskyandzenithairglowobservations AT scheerj characterizationofexceptionallystrongmesosphericwaveeventsusingallskyandzenithairglowobservations AT reisiner characterizationofexceptionallystrongmesosphericwaveeventsusingallskyandzenithairglowobservations AT baumgardnerj characterizationofexceptionallystrongmesosphericwaveeventsusingallskyandzenithairglowobservations AT mendillom characterizationofexceptionallystrongmesosphericwaveeventsusingallskyandzenithairglowobservations |
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1807317153239531520 |