DOI: 10.1029/2018JA025365
Scopus记录号: 2-s2.0-85046744495
论文题名: Quasi-6-Day Wave Modulation of the Equatorial Electrojet
作者: Yamazaki Y. ; Stolle C. ; Matzka J. ; Alken P.
刊名: Journal of Geophysical Research: Space Physics
ISSN: 21699380
出版年: 2018
卷: 123, 期: 5 起始页码: 4094
结束页码: 4109
语种: 英语
英文关键词: CHAMP
; day-to-day variability
; equatorial electrojet (EEJ)
; quasi-6-day wave
; Swarm
; vertical coupling
英文摘要: The equatorial electrojet is an enhanced eastward current in the dayside E region ionosphere flowing along the magnetic equator. The equatorial electrojet is highly variable as it is subject to various forcing mechanisms including atmospheric waves from the lower layers of the atmosphere. There are occasionally times when the intensity of the equatorial electrojet at a fixed longitude shows an oscillatory variation with a period of approximately 6 days. We present case studies of such events based on the equatorial electrojet measurements from the CHAMP and Swarm satellites. The spatial and temporal variability of the equatorial electrojet intensity during these events reveals characteristics of a westward propagating wave with zonal wavenumber 1, consistent with the effect of the quasi-6-day planetary wave. Analyses of the geopotential height data from the Aura satellite confirm the presence of the quasi-6-day planetary wave in the lower thermosphere during the events. The amplitude of the quasi-6-day variation in the equatorial electrojet intensity depends on longitude, but no systematic longitudinal dependence is found for different events. During the event of August 2010, quasi-6-day variations are also observed by ground-based magnetometers and a radar in the Peruvian sector. The effect of the quasi-6-day wave accounts for up to ±5.9 m/s in the equatorial vertical plasma velocity at noon, which is much larger than previously predicted by a numerical model. These results suggest that the quasi-6-day planetary wave is an important source of short-term variability in the equatorial ionosphere. ©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/113956
Appears in Collections: 气候减缓与适应
There are no files associated with this item.
作者单位: GFZ German Research Centre for Geosciences, Potsdam, Germany; Faculty of Science, University of Potsdam, Potsdam, Germany; Cooperative Institute for Research in Environmental Sciences, University of Colorado Boulder, Boulder, CO, United States; National Centers for Environmental Information, NOAA, Boulder, CO, United States
Recommended Citation:
Yamazaki Y.,Stolle C.,Matzka J.,et al. Quasi-6-Day Wave Modulation of the Equatorial Electrojet[J]. Journal of Geophysical Research: Space Physics,2018-01-01,123(5)