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The growth of ring current/SYM-H under northward IMF $B_z$ conditions present during the 21-22 January 2005 geomagnetic storm
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  • Diptiranjan Rout,
  • Swadesh Patra,
  • Sandeep Kumar,
  • Dibyendu Chakrabarty,
  • Geoffrey D. Reeves,
  • Claudia Stolle,
  • Kuldeep Pandey,
  • Shibaji Chakraborty,
  • Edmund A. Spencer
Diptiranjan Rout
GFZ German Research Centre for Geosciences

Corresponding Author:[email protected]

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Swadesh Patra
University of New Brunswick
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Sandeep Kumar
Institute for Space-Earth Environmental Research, Nagoya University
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Dibyendu Chakrabarty
Physical Research Laboratory
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Geoffrey D. Reeves
Space Science and Applications Group, Los Alamos National Laboratory, Los Alamos, New Mexico, USA.
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Claudia Stolle
Leibniz Institut of Atmosphereic Physics at the University of Rostock
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Kuldeep Pandey
University of Saskatchewan
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Shibaji Chakraborty
Virginia Tech
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Edmund A. Spencer
University of South Alabama
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The total energy transfer from the solar wind to the magnetosphere is governed by the reconnection rate at the magnetosphere edges as the IMF $B_z$ turns southward. The delayed response of the ring current to solar wind driving can account for the anomalous growth of the SYM-H under northward IMF $B_z$. The geomagnetic storm on 21-22 January 2005 is considered to be anomalous as the SYM-H index that signifies the strength of ring current, grows and has a sustained peak value lasting more than 6 hrs under northward IMF $B_z$ conditions. In this work, first the standard WINDMI model is utilized to estimate the growth and decay of various magnetospheric currents by using several solar wind-magnetopsehre coupling functions. However, it is found that the WINDMI model driven by any of these coupling functions is not fully able to explain the enhancement of SYM-H under northward IMF $B_z$. The SYM-H variations during the entire duration of the storm were only reproduced when the effects of the dense plasma sheet were included in the WINDMI model. The limitations of directly-driven models relying purely on the solar wind parameters and not accounting for the state of the magnetosphere are highlighted by this work.
21 Apr 2023Submitted to ESS Open Archive
30 Apr 2023Published in ESS Open Archive