Energetics of a substorm on 15 August, 2001: Comparing empirical methods and a global MHD simulation

EI Tanskanen*, M Palmroth, TI Pulkkinen, HEJ Koskinen, P Janhunen, N Ostgaard, JA Slavin, K Liou

*Corresponding author for this work

Research output: Chapter in Book/Report/Conference proceedingConference contributionScientificpeer-review

Abstract

Energy transferred from the solar wind into the magnetosphere-ionosphere system is dissipated largely through the occurrence of substorms. In this paper, a substorm that occurred on 15 August, 2001, between 0220 and 0620 UT is analyzed using several empirical estimates for energy input, for Joule heating and for electron precipitation. The total energy input is estimated in terms of Akasofu's epsilon parameter, with original scaling parameter l(0) = 7R(E) and revised scaling l(0) = 10R(E). Empirically estimated energy input is compared to the results of a GUMICS-4 global MHD simulation. Temporal variation of the input curves compare favorably during substorm growth and expansion phases, while there are differences during the substorm recovery phase. Global electron energy dissipation given by PIXIE on board the POLAR spacecraft matches nicely to the results of the GUMICS-4 simulation in temporal variations, but the absolute levels of dissipation are quite different. (c) 2005 Published by Elsevier Ltd on behalf of COSPAR.

Original languageEnglish
Title of host publicationSOLAR WIND-MAGNETOSPHERE-IONOSPHERE DYNAMICS AND RADIATION MODELS
EditorsT Mukai, R Lopez, K Maezawa, M Grande, JF Fennell, D Heynderickx
Pages1825-1829
Number of pages5
DOIs
Publication statusPublished - 2005
MoE publication typeA4 Article in a conference publication
Event2nd World Space Congress/34th COSPAR Scientific Assembly - Houston, United States
Duration: 10 Oct 200219 Oct 2002

Publication series

NameADVANCES IN SPACE RESEARCH
PublisherELSEVIER SCIENCE LTD
Volume36
ISSN (Print)0273-1177

Conference

Conference2nd World Space Congress/34th COSPAR Scientific Assembly
CountryUnited States
CityHouston
Period10/10/200219/10/2002

Keywords

  • substrom
  • substrom energetics
  • global MHD simulation
  • substrom on 15 August 2001
  • PLASMA SHEET
  • SOLAR-WIND
  • ENERGY
  • CONDUCTANCES
  • MAGNETOTAIL
  • FLUX

Cite this