A storm time assimilative mapping of ionospheric electrodynamics analysis for the severe geomagnetic storm of November 8-9, 1991
- Univ. of Michigan, Ann Arbor, MI (United States)
- National Center for Atmospheric Research, Boulder, CO (United States); and others
Global parameters are obtained for the November 8-9, 1991, severe geomagnetic storm with the application of a slightly modified version of the Assimilative Mapping of Ionospheric Electrodynamics (AMIE) data inversion model. Inputs to the model include ground magnetometer data, satellite electron precipitation data, satellite ion drift data, and ion drift velocities obtained from radar measurements. The authors compare two of the AMIE computed parameters, the total Joule heating and the polar cap potential, to both the AE (12) index and the AE{sub AMIE} index, an AMIE modeled AE index created specifically for severe storm times. The equation obtained from a linear fit to the total Joule heating versus the AE{sub AMIE} index, closely resembles other equations found during much less disturbed times using the AE(12) index. These results using the AE(12) index appear to saturate at a level around 1300 nT. However, this saturation is associated with the calculation of the AE(12) index and not a physical result. An apparent saturation can also be seen in the comparison of the polar cap potential with the AE(12) index, but this is not the case when using the AE{sub AMIE} index. The comparison between the polar cap potential and the AE{sub AMIE} index yields an approximate linear relationship with a correlation coefficient of 0.80. From these results, the authors find that the magnitude of the auroral electrojets and the polar cap potential drop do not show signs of saturation at the activity levels that were present during the November 8-9, 1991 severe storm. 37 refs., 9 figs., 3 tabs.
- OSTI ID:
- 227136
- Journal Information:
- Journal of Geophysical Research, Vol. 100, Issue A10; Other Information: PBD: 1 Oct 1995
- Country of Publication:
- United States
- Language:
- English
Similar Records
Saturation of the auroral electrojet current and the polar cap potential
Global measures of ionospheric electrodynamic activity inferred from combined incoherent scatter radar and ground magnetometer observations