An MHD Study of Geoeffectiveness of a CIR/ HSS Storm Event
Location
Yosemite National Park
Start Date
2-12-2014 6:25 PM
End Date
2-12-2014 6:40 PM
Description
We investigate how the inner magnetosphere responds to the 8 -9 March 2008 corotating interaction region (CIR)/high-speed stream (HSS) storm event. We examine the storm in detail by carrying out high-resolution global magnetohydrodynamic (MHD) simulations using solar wind and interplanetary magnetic field data from upstream spacecraft. This storm was characterized by the arrival of a density plug associated with a CIR at ~0730 UT on 8 March, followed by the commencement of the HSS at ~1830 on the same day. This was followed by another density plug at ~0140 UT the following day on 9 March, which really is the main phase of this storm. For this storm, we found that the MHD simulation ring current energy density responded linearly to increases in dynamic pressure during the northward IMF intervals of the CIR portion of the event. However, there was no correlation between the ring current energy density and solar wind dynamic pressure during the southward IMF intervals of the CIR portion of the event and during the HSS portion of the event. We also analyzed several other CME- and CIR-driven storms in order to determine the geoeffectiveness of various solar wind drivers during geomagnetic storms. We will also compare our MHD simulation results with observations from the THEMIS spacecraft in the magnetotail.
An MHD Study of Geoeffectiveness of a CIR/ HSS Storm Event
Yosemite National Park
We investigate how the inner magnetosphere responds to the 8 -9 March 2008 corotating interaction region (CIR)/high-speed stream (HSS) storm event. We examine the storm in detail by carrying out high-resolution global magnetohydrodynamic (MHD) simulations using solar wind and interplanetary magnetic field data from upstream spacecraft. This storm was characterized by the arrival of a density plug associated with a CIR at ~0730 UT on 8 March, followed by the commencement of the HSS at ~1830 on the same day. This was followed by another density plug at ~0140 UT the following day on 9 March, which really is the main phase of this storm. For this storm, we found that the MHD simulation ring current energy density responded linearly to increases in dynamic pressure during the northward IMF intervals of the CIR portion of the event. However, there was no correlation between the ring current energy density and solar wind dynamic pressure during the southward IMF intervals of the CIR portion of the event and during the HSS portion of the event. We also analyzed several other CME- and CIR-driven storms in order to determine the geoeffectiveness of various solar wind drivers during geomagnetic storms. We will also compare our MHD simulation results with observations from the THEMIS spacecraft in the magnetotail.