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| Titel |
Venus' atmospheric waves indicated by ground-based dayside infrared spectroscopic observation |
| VerfasserIn |
Mayu Hosouchi, Naomoto Iwagami, Shoko Ohtsuki, Masahiro Takagi |
| Konferenz |
EGU General Assembly 2011
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| Medientyp |
Artikel
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| Sprache |
Englisch
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| Digitales Dokument |
PDF |
| Erschienen |
In: GRA - Volume 13 (2011) |
| Datensatznummer |
250045572
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| Zusammenfassung |
| In the Venus’ atmosphere, waves of various scales transport angular momentum and play an
important role in the atmosphere. For example, the mechanism of the super rotation may be
explained by the equatorial Kelvin wave [Yamamoto & Tanaka, 1997] or by the thermal tides
[Takagi & Matsuda, 2007].
Most of studies have focused on the ultraviolet region to observe atmospheric waves at 70
km [Del Genio et al., 1982, 1990]. Several studies have focused on the infrared region and
analyzed thermal emission from the nightside to observe atmospheric waves at 50 km [Belton
et al., 1991]. In contrast, we observed the dayside by infrared spectroscopy to quantify CO2
column density above 60 – 65 km. We performed infrared spectroscopic measurements at the
NASA Infrared Telescope Facility (IRTF) with CSHELL spectrometer in May and Nov.
2007, Jun. 2009 and Aug. 2010. We derive representative height to study atmospheric
waves.
In this presentation, we will show the clouds structure at 60 – 65 km. The clouds structure
varied 2007 to 2010. We estimate that CO2 column density above 60 – 65 km increased 10 –
30 % in this term. The change suggests that the Venus’ atmosphere changes gradually year by
year. Previous observations assumed a latitudinally uniform atmospheric circulation
[Belton et al., 1991; Crisp et al., 1991]. In contrast, we take latitudinal variations into
account.
Then, we will compare these results with those of Venus Express. |
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