DOI: 10.1029/2018JA025190
Scopus记录号: 2-s2.0-85047630089
论文题名: On the Role of Last Closed Drift Shell Dynamics in Driving Fast Losses and Van Allen Radiation Belt Extinction
作者: Olifer L. ; Mann I.R. ; Morley S.K. ; Ozeke L.G. ; Choi D.
刊名: Journal of Geophysical Research: Space Physics
ISSN: 21699380
出版年: 2018
卷: 123, 期: 5 起始页码: 3692
结束页码: 3703
语种: 英语
英文关键词: inner magnetosphere
; magnetopause shadowing
; radiation belts
英文摘要: We present observations of very fast radiation belt loss as resolved using high time resolution electron flux data from the constellation of Global Positioning System (GPS) satellites. The time scale of these losses is revealed to be as short as ∼0.5–2 hr during intense magnetic storms, with some storms demonstrating almost total loss on these time scales and which we characterize as radiation belt extinction. The intense March 2013 and March 2015 storms both show such fast extinction, with a rapid recovery, while the September 2014 storm shows fast extinction but no recovery for around 2 weeks. By contrast, the moderate September 2012 storm which generated a three radiation belt morphology shows more gradual loss. We compute the last closed drift shell (LCDS) for each of these four storms and show a very strong correspondence between the LCDS and the loss patterns of trapped electrons in each storm. Most significantly, the location of the LCDS closely mirrors the high time resolution losses observed in GPS flux. The fast losses occur on a time scale shorter than the Van Allen Probes orbital period, are explained by proximity to the LCDS, and progress inward, consistent with outward transport to the LCDS by fast ultralow frequency wave radial diffusion. Expressing the location of the LCDS in L*, and not model magnetopause standoff distance in units of RE, clearly reveals magnetopause shadowing as the cause of the fast loss observed by the GPS satellites. ©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/114033
Appears in Collections: 气候减缓与适应
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作者单位: Department of Physics, University of Alberta, Edmonton, AB, Canada; Space Science and Applications Group, Los Alamos National Laboratory, Los Alamos, NM, United States
Recommended Citation:
Olifer L.,Mann I.R.,Morley S.K.,et al. On the Role of Last Closed Drift Shell Dynamics in Driving Fast Losses and Van Allen Radiation Belt Extinction[J]. Journal of Geophysical Research: Space Physics,2018-01-01,123(5)