Global distribution and parameter dependences of gravity wave activity in the Martian upper thermosphere derived from MAVEN/NGIMS observations

Naoki Terada 1 François Leblanc 2 Hiromu Nakagawa 1 Alexander S. Medvedev 3, 4 Erdal Yiğit 5, 4 Takeshi Kuroda 6, 1 Takuya Hara 7 Scott L. England 7 Hitoshi Fujiwara 8 Kaori Terada 1 Kanako Seki 9, 10 Paul R. Mahaffy 11 Meredith Elrod 12, 11 Mehdi Benna 11, 12 Joseph Grebowsky 11 Bruce M. Jakosky 13
1 Graduate School of Information Sciences [Sendai]
2 HEPPI - LATMOS
LATMOS - Laboratoire Atmosphères, Milieux, Observations Spatiales
3 MPS - Max-Planck-Institut für Sonnensystemforschung
4 Institut für Astrophysik [Göttingen]
5 Department of Physics and Astronomy [Fairfax]
6 NICT - National Institute of Information and Communications Technology
7 SSL - Space Sciences Laboratory [Berkeley]
8 Faculty of Science and Technology [Tokyo]
9 Department of Earth and Planetary Science [Tokyo]
10 Graduate School of Science [Tokyo]
11 GSFC - NASA Goddard Space Flight Center
12 CRESST - Center for Research and Exploration in Space Science and Technology [GSFC]
13 LASP - Laboratory for Atmospheric and Space Physics [Boulder]
Abstract : Wavelike perturbations in the Martian upper thermosphere observed by the Neutral Gas Ion Mass Spectrometer (NGIMS) onboard the Mars Atmosphere and Volatile EvolutioN (MAVEN) spacecraft have been analyzed. The amplitudes of small-scale perturbations with apparent wavelengths between ~100 and ~500 km in the Ar density around the exobase show a clear dependence on temperature (T0) of the upper thermosphere. The average amplitude of the perturbations is ~10% on the dayside and ~20% on the nightside, which is about 2 and 10 times larger than those observed in the Venusian upper thermosphere and in the low-latitude region of Earth's upper thermosphere, respectively. The amplitudes are inversely proportional to T0, suggesting saturation due to convective instability in the Martian upper thermosphere. After removing the dependence on T0, dependences of the average amplitude on the geographic latitude and longitude and solar wind parameters are found to be not larger than a few percent. These results suggest that the amplitudes of small-scale perturbations are mainly determined by convective breaking/saturation in the upper thermosphere on Mars, unlike those on Venus and Earth.
Keywords : MAVEN gravity waves upper thermosphere Mars
Document type :
Journal articles
Complete list of metadatas
https://hal-insu.archives-ouvertes.fr/insu-01492717
Contributor : Catherine Cardon <>
Submitted on : Monday, March 20, 2017 - 3:02:58 PM
Last modification on : Friday, January 10, 2020 - 3:42:33 PM

Identifiers

Collections

INSU | CNRS | LATMOS | UPMC | UVSQ | UNIV-PARIS-SACLAY | SORBONNE-UNIVERSITE | SU-SCIENCES

Citation

Naoki Terada, François Leblanc, Hiromu Nakagawa, Alexander S. Medvedev, Erdal Yiğit, et al.. Global distribution and parameter dependences of gravity wave activity in the Martian upper thermosphere derived from MAVEN/NGIMS observations. Journal of Geophysical Research Space Physics, American Geophysical Union/Wiley, 2017, 122 (2), pp.2374-2397. ⟨10.1002/2016JA023476⟩. ⟨insu-01492717⟩

Export

BibTeX TEI DC DCterms EndNote

Share

Metrics

Record views

237

Contact

Informations

CCSD