DOI: 10.1002/2017JA024921
Scopus记录号: 2-s2.0-85047554255
论文题名: An Auroral Boundary-Oriented Model of Subauroral Polarization Streams (SAPS)
作者: Landry R.G. ; Anderson P.C.
刊名: Journal of Geophysical Research: Space Physics
ISSN: 21699380
出版年: 2018
卷: 123, 期: 4 起始页码: 3154
结束页码: 3169
语种: 英语
英文关键词: magnetosphere-ionosphere coupling
; SAPS
; subauroral
英文摘要: An empirical model of subauroral polarization stream (SAPS) electric fields has been developed using measurements of ion drifts and particle precipitation made by the Defense Meteorological Satellite Program from 1987 to 2012 and Dynamics Explorer 2 as functions of magnetic local time (MLT), magnetic latitude, the auroral electrojet index (AE), hemisphere, and day of year. Over 500,000 subauroral passes are used. This model is oriented in degree magnetic latitude equatorward of the aurora and takes median values instead of the mean to avoid the contribution of low occurrence frequency subauroral ion drifts so that the model is representative of the much more common, latitudinally broad, low-amplitude SAPS field. The SAPS model is in broad agreement with previous statistical efforts in the variation of the SAPS field with MLT and magnetic activity level, although the median field is weaker. Furthermore, we find that the median SAPS field is roughly conjugate in both hemispheres for all seasons, with a maximum in SAPS amplitude and width found for 1800–2000 MLT. The SAPS amplitude is found to vary seasonally only from about 1800–2000 MLT, maximizing in both hemispheres during equinox months. Because this feature exists despite controlling for the AE index, it is suggested that this is due to a seasonal variation in the flux tube averaged ionospheric conductance at MLT sectors where it is more likely that one flux tube footprint is in darkness while the other is in daylight. ©2018. American Geophysical Union. All Rights Reserved. Citation statistics:
资源类型: 期刊论文
标识符: http://119.78.100.158/handle/2HF3EXSE/114107
Appears in Collections: 气候减缓与适应
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作者单位: Center for Space Sciences, University of Texas at Dallas, Richardson, TX, United States
Recommended Citation:
Landry R.G.,Anderson P.C.. An Auroral Boundary-Oriented Model of Subauroral Polarization Streams (SAPS)[J]. Journal of Geophysical Research: Space Physics,2018-01-01,123(4)