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小郷原 一智 所属 京都産業大学 理学部 宇宙物理・気象学科 職種 准教授 |
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| 言語種別 | 英語 |
| 発行・発表の年月 | 2017/02 |
| 形態種別 | 研究論文 |
| 査読 | 査読あり |
| 標題 | Large stationary gravity wave in the atmosphere of Venus |
| 執筆形態 | その他 |
| 掲載誌名 | NATURE GEOSCIENCE |
| 出版社・発行元 | NATURE PUBLISHING GROUP |
| 巻・号・頁 | 10(2),pp.85-+ |
| 著者・共著者 | Tetsuya Fukuhara,Masahiko Futaguchi,George L. Hashimoto,Takeshi Horinouchi,Takeshi Imamura,Naomoto Iwagaimi,Toru Kouyama,Shin-ya Murakami,Masato Nakamura,Kazunori Ogohara,Mitsuteru Sato,Takao M. Sato,Makoto Suzuki,Makoto Taguchi,Seiko Takagi,Munetaka Ueno,Shigeto Watanabe,Manabu Yamada,Atsushi Yamazaki |
| 概要 | The planet Venus is covered by thick clouds of sulfuric acid that move westwards because the entire upper atmosphere rotates much faster than the planet itself. At the cloud tops, about 65 km in altitude, small-scale features are predominantly carried by the background wind at speeds of approximately 100 ms(-1). In contrast, planetary-scale atmospheric features have been observed to move slightly faster or slower than the background wind, a phenomenon that has been interpreted to reflect the propagation of planetary-scale waves. Here we report the detection of an interhemispheric bow-shaped structure stretching 10,000 km across at the cloud-top level of Venus in middle infrared and ultraviolet images from the Japanese orbiter Akatsuki. Over several days of observation, the bow-shaped structure remained relatively fixed in position above the highland on the slowly rotating surface, despite the background atmospheric super rotation. We suggest that the bow-shaped structure is the result of an atmospheric gravity wave generated in the lower atmosphere by mountain topography that then propagated upwards. Numerical simulations provide preliminary support for this interpretation, but the formation and propagation of a mountain gravity wave remain difficult to reconcile with assumed near-surface conditions on Venus. We suggest that winds in the deep atmosphere may be spatially or temporally more variable than previously thought. |
| DOI | 10.1038/NGEO2873 |
| ISSN | 1752-0894/1752-0908 |
| Put Code(ORCID) | 52343300 |
| PermalinkURL | http://www.scopus.com/inward/record.url?eid=2-s2.0-85020574141&partnerID=MN8TOARS |
| researchmap用URL | http://orcid.org/0000-0001-7666-4442 |