DOI: 10.1029/2017JA025138
Scopus记录号: 2-s2.0-85047806810
论文题名: Ionospheric Electron Heating Associated With Pulsating Auroras: Joint Optical and PFISR Observations
作者: Liang J. ; Donovan E. ; Reimer A. ; Hampton D. ; Zou S. ; Varney R.
刊名: Journal of Geophysical Research: Space Physics
ISSN: 21699380
出版年: 2018
卷: 123, 期: 5 起始页码: 4430
结束页码: 4456
语种: 英语
英文关键词: electron heating
; heat flux
; low-energy electrons
; PFISR
; pulsating aurora
英文摘要: In a recent study, Liang et al. (2017, https://doi.org/10.1002/2017JA024127) repeatedly identified strong electron temperature (Te) enhancements when Swarm satellites traversed pulsating auroral patches. In this study, we use joint optical and Poker Flat Incoherent Scatter Radar (PFISR) observations to further investigate the F region plasma signatures related to pulsating auroras. On 19 March 2015 night, which contained multiple intervals of pulsating auroral activities, we identify a statistical trend, albeit not a one-to-one correspondence, of strong Te enhancements (~500–1000 K) in the upper F region ionosphere during the passages of pulsating auroras over PFISR. On the other hand, there is no discernible and repeatable density enhancement in the upper F region during pulsating auroral intervals. Collocated optical and NOAA satellite observations suggest that the pulsating auroras are composed of energetic electron precipitation with characteristic energy >10 keV, which is inefficient in electron heating in the upper F region. Based upon PFISR observations and simulations from Liang et al. (2017) model, we propose that thermal conduction from the topside ionosphere, which is heated by precipitating low-energy electrons, offers the most likely explanation for the observed electron heating in the upper F region associated with pulsating auroras. Such a heating mechanism is similar to that underlying the “stable auroral red arcs” in the subauroral ionosphere. Our proposal conforms to the notion on the coexistence of an enhanced cold plasma population and the energetic electron precipitation, in magnetospheric flux tubes threading the pulsating auroral patch. In addition, we find a trend of enhanced ion upflows during pulsating auroral intervals. ©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/113949
Appears in Collections: 气候减缓与适应
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作者单位: Department of Physics and Astronomy, University of Calgary, Calgary, AB, Canada; SRI Internatoinal, Menlo Park, CA, United States; Geophysical Institute, University of Alaska Fairbanks, Fairbanks, AK, United States; Department of Climate and Space Sciences and Engineering, University of Michigan, Ann Arbor, MI, United States
Recommended Citation:
Liang J.,Donovan E.,Reimer A.,et al. Ionospheric Electron Heating Associated With Pulsating Auroras: Joint Optical and PFISR Observations[J]. Journal of Geophysical Research: Space Physics,2018-01-01,123(5)