HR: 0800h
AN: SA21C-0370 [Abstracts]
TI: 2D Modeling of Geomagnetic Induction near Coastal Regions
AU: * Shepherd, S G
EM: simon@thayer.dartmouth.edu
AF: Thayer School of Engineering, Dartmouth College, 8000 Cummings Hall, Hanover, NH 03755
United States
AU: Shubitidze, F
EM: Fridon.Shubitidze@Dartmouth.EDU
AF: Thayer School of Engineering, Dartmouth College, 8000 Cummings Hall, Hanover, NH 03755
United States
AB:
Accurate calculation of the electric and magnetic fields induced in
the Earth by time-varying ionospheric currents is an important step
in computing the strength of geomagmatically induced currents (GICs)
and in accurately inferring the strength and location of the source
currents from ground-based magnetometers. The complexity of the
Earth's conductivity adds to the difficulty of the problem, particularly
near coastal regions where the conductivity of salt water is several
orders of magnitude larger than that of the surrounding land mass.
We demonstrate the use of a numerical technique known as the method
of auxiliary sources (MAS) to calculate the induced electric and magnetic
fields, resulting from a uniform source, near a 2D modeled coast. Dependence
of the resulting fields on frequency, conductivity, and geometry are shown.
DE: 2409 Current systems (2708)
DE: 1515 Geomagnetic induction
DE: 0619 Electromagnetic theory
DE: 0644 Numerical methods
SC: SPA-Aeronomy [SA]
MN: 2004 AGU Fall Meeting