Testing nowcasts of the ionospheric convection from the expanding and contracting polar cap model

Walach, M. T. and Milan, S. E. and Yeoman, T. K. and Hubert, B. A. and Hairston, M. R. (2017) Testing nowcasts of the ionospheric convection from the expanding and contracting polar cap model. Space Weather, 15 (4). pp. 623-636. ISSN 1539-4956

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The expanding/contracting polar cap (ECPC) model, or the time-dependent Dungey cycle, provides a theoretical framework for understanding solar wind-magnetosphere-ionosphere coupling. The ECPC describes the relationship between magnetopause reconnection and substorm growth phase, magnetotail reconnection and substorm expansion phase, associated changes in auroral morphology, and ionospheric convective motions. Despite the many successes of the model, there has yet to be a rigorous test of the predictions or nowcasts made regarding ionospheric convection, which remains a final hurdle for the validation of the ECPC. In this study we undertake a comparison of ionospheric convection, as measured in situ by ion drift meters on board DMSP (Defense Meteorological Satellite Program) satellites and from the ground by SuperDARN (Super Dual Auroral Radar Network), with motions nowcasted by a theoretical model. The model is coupled to measurements of changes in the size of the polar cap made using global auroral imagery from the IMAGE FUV (Imager for Magnetopause to Aurora Global Exploration Far Ultraviolet) instrument, as well as the dayside reconnection rate, estimated using the OMNI data set. The results show that we can largely nowcast the magnitudes of ionospheric convection flows using the context of our understanding of magnetic reconnection at the magnetopause and in the magnetotail.

Item Type:
Journal Article
Journal or Publication Title:
Space Weather
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©2017. The Authors. This is an open access article under the terms of the Creative Commons Attribution License, which permits use, distribution and reproduction in any medium, provided the original work is properly cited.
Uncontrolled Keywords:
?? dungey cycleionospheric convectionsolar wind-magnetosphere-ionosphere couplingatmospheric science ??
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Deposited On:
08 May 2017 15:10
Last Modified:
13 Nov 2023 00:19