2009年3月
Three-dimensional simulation of the coupled Perkins and E-s-layer instabilities in the nighttime midlatitude ionosphere
JOURNAL OF GEOPHYSICAL RESEARCH-SPACE PHYSICS
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- 巻
- 114
- 号
- 3
- 記述言語
- 英語
- 掲載種別
- 研究論文(学術雑誌)
- DOI
- 10.1029/2008JA013789
- 出版者・発行元
- AMER GEOPHYSICAL UNION
Plasma density structures and associated irregularities in the nighttime midlatitude ionosphere are frequently observed as frontal structures elongated from northwest to southeast (NW-SE) in the Northern Hemisphere. The frontal structures and the coupling process between the E and F regions are studied with a three-dimensional numerical model, which can simulate two instability mechanisms: Perkins instability in the F-region and sporadic-E (E-s)-layer instability in the E region. The fastest growth of the coupled instability occurs when the unstable conditions on NW-SE perturbation are satisfied in both regions. The perturbation of F-region integrated conductivity grows much faster than the isolated Perkins instability. The meridional component of a rotational wind shear blows an existing E-s layer southward, and the F-region structure follows the E-region drift velocity. The NW-SE structure in the E region can be formed from random perturbation regardless of the F-region condition. When the F region is unstable on the NW-SE perturbation, however, the NW-SE structure is formed in both regions with a common scale length. We conclude that (1) the E-s-layer instability plays a major role in seeding NW-SE structure in the F region, and the Perkins instability is required to amplify its perturbation; (2) the rotational wind shear in the E region produces southwestward phase propagation of the NW-SE structure in both the E and F regions; and (3) the coupling process has a significant effect on the scale of the E-s-layer perturbation rather than the growth rate of the E-s-layer instability.
- リンク情報
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- DOI
- https://doi.org/10.1029/2008JA013789
- Web of Science
- https://gateway.webofknowledge.com/gateway/Gateway.cgi?GWVersion=2&SrcAuth=JSTA_CEL&SrcApp=J_Gate_JST&DestLinkType=FullRecord&KeyUT=WOS:000264441200003&DestApp=WOS_CPL
- URL
- http://www.scopus.com/inward/record.url?eid=2-s2.0-67649099565&partnerID=MN8TOARS
- URL
- http://orcid.org/0000-0002-4957-764X
- ID情報
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- DOI : 10.1029/2008JA013789
- ISSN : 2169-9380
- eISSN : 2169-9402
- ORCIDのPut Code : 49519997
- SCOPUS ID : 67649099565
- Web of Science ID : WOS:000264441200003