Average characteristics and activity dependence of the subauroral polarization stream
[1] Data from the Millstone Hill incoherent scatter radar taken over two solar cycles (1979–2000) are examined to determine the average characteristics of the disturbance convection electric field in the midlatitude ionosphere. Radar azimuth scans provide a regular database of ionospheric plasma con...
| Main Authors: | , |
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| Other Authors: | |
| Format: | Article |
| Language: | en_US |
| Published: |
American Geophysical Union (AGU)
2018
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| Online Access: | http://hdl.handle.net/1721.1/114701 |
| _version_ | 1826203153421303808 |
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| author | Foster, John C Vo, H. B. |
| author2 | Haystack Observatory |
| author_facet | Haystack Observatory Foster, John C Vo, H. B. |
| author_sort | Foster, John C |
| collection | MIT |
| description | [1] Data from the Millstone Hill incoherent scatter radar taken over two solar cycles (1979–2000) are examined to determine the average characteristics of the disturbance convection electric field in the midlatitude ionosphere. Radar azimuth scans provide a regular database of ionospheric plasma convection observations spanning auroral and subauroral latitudes, and these scans have been examined for all local times and activity conditions.We examine the occurrence and characteristics of a persistent secondary westward convection peak which lies equatorward of the auroral two‐cell convection. Individual scans and average patterns of plasma flow identify and characterize this latitudinally broad and persistent subauroral polarization stream (SAPS), which spans the nightside from dusk to the early morning sector for all Kp greater than 4. Premidnight, the SAPS westward convection lies equatorward of L = 4 (60° invariant latitude, Λ), spans 3°–5° of latitude, and has an average peak amplitude of >900 m/s. In the predawn sector, SAPS is seen as a region of antisunward convection equatorward of L = 3 (55° Λ), spanning ∼3° of latitude, with an average peak amplitude of 400 m/s. |
| first_indexed | 2024-09-23T12:32:10Z |
| format | Article |
| id | mit-1721.1/114701 |
| institution | Massachusetts Institute of Technology |
| language | en_US |
| last_indexed | 2024-09-23T12:32:10Z |
| publishDate | 2018 |
| publisher | American Geophysical Union (AGU) |
| record_format | dspace |
| spelling | mit-1721.1/1147012022-10-01T09:39:19Z Average characteristics and activity dependence of the subauroral polarization stream Foster, John C Vo, H. B. Haystack Observatory John C. Foster Foster, John C Vo, H. B. [1] Data from the Millstone Hill incoherent scatter radar taken over two solar cycles (1979–2000) are examined to determine the average characteristics of the disturbance convection electric field in the midlatitude ionosphere. Radar azimuth scans provide a regular database of ionospheric plasma convection observations spanning auroral and subauroral latitudes, and these scans have been examined for all local times and activity conditions.We examine the occurrence and characteristics of a persistent secondary westward convection peak which lies equatorward of the auroral two‐cell convection. Individual scans and average patterns of plasma flow identify and characterize this latitudinally broad and persistent subauroral polarization stream (SAPS), which spans the nightside from dusk to the early morning sector for all Kp greater than 4. Premidnight, the SAPS westward convection lies equatorward of L = 4 (60° invariant latitude, Λ), spans 3°–5° of latitude, and has an average peak amplitude of >900 m/s. In the predawn sector, SAPS is seen as a region of antisunward convection equatorward of L = 3 (55° Λ), spanning ∼3° of latitude, with an average peak amplitude of 400 m/s. 2018-04-13T15:19:42Z 2018-04-13T15:19:42Z 2002-12 2002-09 Article http://purl.org/eprint/type/JournalArticle 2169-9380 2169-9402 http://hdl.handle.net/1721.1/114701 Foster, J. C., and H. B. Vo. “Average Characteristics and Activity Dependence of the Subauroral Polarization Stream.” Journal of Geophysical Research: Space Physics 107, A12 (December 2002): 1475 © 2002 American Geophysical Union en_US http://dx.doi.org/10.1029/2002JA009409 Journal of Geophysical Research: Space Physics Article is made available in accordance with the publisher's policy and may be subject to US copyright law. Please refer to the publisher's site for terms of use. application/pdf American Geophysical Union (AGU) John C. Foster |
| spellingShingle | Foster, John C Vo, H. B. Average characteristics and activity dependence of the subauroral polarization stream |
| title | Average characteristics and activity dependence of the subauroral polarization stream |
| title_full | Average characteristics and activity dependence of the subauroral polarization stream |
| title_fullStr | Average characteristics and activity dependence of the subauroral polarization stream |
| title_full_unstemmed | Average characteristics and activity dependence of the subauroral polarization stream |
| title_short | Average characteristics and activity dependence of the subauroral polarization stream |
| title_sort | average characteristics and activity dependence of the subauroral polarization stream |
| url | http://hdl.handle.net/1721.1/114701 |
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