MHD simulations of quadrupolar paleomagnetospheres

Details MHD simulations of quadrupolar paleomagnetospheres MHD simulations of quadrupolar paleomagnetospheres

Dec 2004

adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=2004jgra..10912221v&link_type=abstract

Journal of Geophysical Research, Volume 109, Issue A12, CiteID A12221

Physics

9

Magnetospheric Physics: Magnetospheric Configuration And Dynamics, Magnetospheric Physics: Solar Wind/Magnetosphere Interactions, Geomagnetism And Paleomagnetism: Archeomagnetism

Scientific paper

During geomagnetic polarity transitions the Earth's internal magnetic field is expected to deviate significantly from the dipolar configuration observed today, and higher-order multipoles can become important. Their effects on the magnetosphere are investigated in this study by means of MHD simulations. We look at quadrupolar configurations and vary the parameters that are expected to be most important in determining the large-scale current systems and the field line topology of such paleomagnetospheres, namely, (1) the orientation of the internal field as well as (2) the orientation of the interplanetary magnetic field (IMF) with respect to the solar wind flow, and (3) the quadrupole shape parameter which controls the topology of the internal field. Zero IMF conditions yield reference cases which allow to locate the magnetopause that otherwise can be obscured by field line merging. Magnetopause currents and cross-tail currents in quadrupolar configurations are contrasted with the tail current system in the present-day dipolar magnetosphere. Interplanetary magnetic fields with a nonzero component perpendicular to the solar wind flow are found to have a much stronger effect on the global magnetospheric configuration than a purely parallel or antiparallel IMF. Since a quadrupole field is more structured than a dipole field, conditions that favor field line merging at the dayside are met regularly in quadrupolar magnetospheres. Solar wind-magnetosphere coupling triggered by reconnection should thus be persistent rather than strongly controlled by solar wind parameters. The investigation presented in this report is part of a multi-institutional collaboration to model the effects of geomagnetic polarity transitions on the Earth's environment in space and the upper and middle atmosphere.

Affiliated with

Also associated with

No associations

Rating

MHD simulations of quadrupolar paleomagnetospheres does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.

If you have personal experience with MHD simulations of quadrupolar paleomagnetospheres, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and MHD simulations of quadrupolar paleomagnetospheres will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFWR-SCP-O-1085854