On the Persistent Shape and Coherence of Pulsating Auroral Patches.
Saved in:
| Title: | On the Persistent Shape and Coherence of Pulsating Auroral Patches. |
|---|---|
| Authors: | Humberset, B. K.1 beate.humberset@uib.no, Gjerloev, J. W.1,2, Mann, I. R.3, Michell, R. G.4,5, Samara, M.5 |
| Source: | Journal of Geophysical Research. Space Physics. May2018, Vol. 123 Issue 5, p4272-4289. 18p. |
| Abstract: | Abstract: The pulsating aurora covers a broad range of fluctuating shapes that are poorly characterized. The purpose of this paper is therefore to provide objective and quantitative measures of the extent to which pulsating auroral patches maintain their shape, drift and fluctuate in a coherent fashion. We present results from a careful analysis of pulsating auroral patches using all‐sky cameras. We have identified four well‐defined individual patches that we follow in the patch frame of reference. In this way we avoid the space‐time ambiguity which complicates rocket and satellite measurements. We find that the shape of the patches is remarkably persistent with 85–100% of the patch being repeated for 4.5–8.5 min. Each of the three largest patches has a temporal correlation with a negative dependence on distance, and thus does not fluctuate in a coherent fashion. A time‐delayed response within the patches indicates that the so‐called streaming mode might explain the incoherency. The patches appear to drift differently from the SuperDARN‐determined E → × B → convection velocity. However, in a nonrotating reference frame the patches drift with 230–287 m/s in a north eastward direction, which is what typically could be expected for the convection return flow. [ABSTRACT FROM AUTHOR] |
| Copyright of Journal of Geophysical Research. Space Physics is the property of Wiley-Blackwell and its content may not be copied or emailed to multiple sites without the copyright holder's express written permission. Additionally, content may not be used with any artificial intelligence tools or machine learning technologies. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.) | |
| Database: | GreenFILE |
| FullText | Text: Availability: 0 |
|---|---|
| Header | DbId: 8gh DbLabel: GreenFILE An: 130750040 AccessLevel: 6 PubType: Academic Journal PubTypeId: academicJournal PreciseRelevancyScore: 0 |
| IllustrationInfo | |
| Items | – Name: Title Label: Title Group: Ti Data: On the Persistent Shape and Coherence of Pulsating Auroral Patches. – Name: Author Label: Authors Group: Au Data: <searchLink fieldCode="AR" term="%22Humberset%2C+B%2E+K%2E%22">Humberset, B. K.</searchLink><relatesTo>1</relatesTo><i> beate.humberset@uib.no</i><br /><searchLink fieldCode="AR" term="%22Gjerloev%2C+J%2E+W%2E%22">Gjerloev, J. W.</searchLink><relatesTo>1,2</relatesTo><br /><searchLink fieldCode="AR" term="%22Mann%2C+I%2E+R%2E%22">Mann, I. R.</searchLink><relatesTo>3</relatesTo><br /><searchLink fieldCode="AR" term="%22Michell%2C+R%2E+G%2E%22">Michell, R. G.</searchLink><relatesTo>4,5</relatesTo><br /><searchLink fieldCode="AR" term="%22Samara%2C+M%2E%22">Samara, M.</searchLink><relatesTo>5</relatesTo> – Name: TitleSource Label: Source Group: Src Data: <searchLink fieldCode="JN" term="%22Journal+of+Geophysical+Research%2E+Space+Physics%22">Journal of Geophysical Research. Space Physics</searchLink>. May2018, Vol. 123 Issue 5, p4272-4289. 18p. – Name: Abstract Label: Abstract Group: Ab Data: Abstract: The pulsating aurora covers a broad range of fluctuating shapes that are poorly characterized. The purpose of this paper is therefore to provide objective and quantitative measures of the extent to which pulsating auroral patches maintain their shape, drift and fluctuate in a coherent fashion. We present results from a careful analysis of pulsating auroral patches using all‐sky cameras. We have identified four well‐defined individual patches that we follow in the patch frame of reference. In this way we avoid the space‐time ambiguity which complicates rocket and satellite measurements. We find that the shape of the patches is remarkably persistent with 85–100% of the patch being repeated for 4.5–8.5 min. Each of the three largest patches has a temporal correlation with a negative dependence on distance, and thus does not fluctuate in a coherent fashion. A time‐delayed response within the patches indicates that the so‐called streaming mode might explain the incoherency. The patches appear to drift differently from the SuperDARN‐determined E → × B → convection velocity. However, in a nonrotating reference frame the patches drift with 230–287 m/s in a north eastward direction, which is what typically could be expected for the convection return flow. [ABSTRACT FROM AUTHOR] – Name: AbstractSuppliedCopyright Label: Group: Ab Data: <i>Copyright of Journal of Geophysical Research. Space Physics is the property of Wiley-Blackwell and its content may not be copied or emailed to multiple sites without the copyright holder's express written permission. Additionally, content may not be used with any artificial intelligence tools or machine learning technologies. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract.</i> (Copyright applies to all Abstracts.) |
| PLink | https://search.ebscohost.com/login.aspx?direct=true&site=eds-live&db=8gh&AN=130750040 |
| RecordInfo | BibRecord: BibEntity: Identifiers: – Type: doi Value: 10.1029/2017JA024405 Languages: – Code: eng Text: English PhysicalDescription: Pagination: PageCount: 18 StartPage: 4272 Titles: – TitleFull: On the Persistent Shape and Coherence of Pulsating Auroral Patches. Type: main BibRelationships: HasContributorRelationships: – PersonEntity: Name: NameFull: Humberset, B. K. – PersonEntity: Name: NameFull: Gjerloev, J. W. – PersonEntity: Name: NameFull: Mann, I. R. – PersonEntity: Name: NameFull: Michell, R. G. – PersonEntity: Name: NameFull: Samara, M. IsPartOfRelationships: – BibEntity: Dates: – D: 01 M: 05 Text: May2018 Type: published Y: 2018 Identifiers: – Type: issn-print Value: 21699380 Numbering: – Type: volume Value: 123 – Type: issue Value: 5 Titles: – TitleFull: Journal of Geophysical Research. Space Physics Type: main |
| ResultId | 1 |
