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On the historical origins of the CEJ, DP2, and Ddyn current systems and their roles in the predictions of ionospheric responses to geomagnetic storms at equatorial latitudes

Citation

Amory-Mazaudier, C and Bolaji, OS and Doumbia, V, On the historical origins of the CEJ, DP2, and Ddyn current systems and their roles in the predictions of ionospheric responses to geomagnetic storms at equatorial latitudes, Journal of Geophysical Research: Space Physics, 122, (7) pp. 7827-7833. ISSN 2169-9380 (2017) [Refereed Article]


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Copyright Statement

© 2017. American Geophysical Union.

DOI: doi:10.1002/2017JA024132

Abstract

In this short letter, we recall the differences between the counter electrojet (CEJ), which is a phenomenon observed on the magnetically quiet days and the disturbance dynamo (Ddyn), which can be observed during and after a geomagnetic storm. The CEJ is well known to occur near the geomagnetic dip equator. It can be identified by a reversal in the horizontal component (H) of the geomagnetic field daily regular variations. In contrast to equatorial electrojet (EEJ) that flows eastward in the daytime, the CEJ is considered to flow westward. The magnetic signatures of the reversed solar quiet (Sq) current at the low latitude during magnetic storms are due to the Ddyn. This disturbance (Ddyn) is produced by current systems that are driven by thermospheric storm winds originating from the Joule heating of enhanced high-latitude currents. The DP2 is the magnetic effect of current systems at high latitudes. These currents are associated with the coupling of magnetosphere and ionosphere through geomagnetic field lines. They are associated to the magnetospheric convection. During intense magnetic storms these high-latitude currents are enhanced and their magnetic effects can extend toward the low latitudes. This work shows that the study of magnetic perturbations makes it possible to understand the disturbances of the ionospheric electric currents. The use of an efficient treatment of the magnetic signals makes it possible to separate the magnetic effects of the different perturbations prompt penetration of the magnetospheric convection electric field and disturbance dynamo electric field. This was performed in the paper Nava et al. (2016).

Item Details

Item Type:Refereed Article
Keywords:CEJ, DP2, Ddyn current systems, geomagnetic storms, ionospheric responses
Research Division:Physical Sciences
Research Group:Space sciences
Research Field:Mesospheric, thermospheric, ionospheric and magnetospheric physics
Objective Division:Environmental Management
Objective Group:Air quality, atmosphere and weather
Objective Field:Atmospheric processes and dynamics
UTAS Author:Bolaji, OS (Dr Olawale Bolaji)
ID Code:123605
Year Published:2017
Web of Science® Times Cited:21
Deposited By:Mathematics and Physics
Deposited On:2018-01-15
Last Modified:2018-04-30
Downloads:89 View Download Statistics

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