Synthetic Magnetogram Code for Magnetosphere-Ionosphere Coupling Models
Abstract
A synthetic magnetogram code was developed to compute realistic ground magnetic field perturbations, based upon input from global MHD models, ring-current models, convection models and global coupled models. The code includes the effects of all large-scale current systems in the MI system and also computes the effects from the inner magnetosphere currents by integrating the Biot-Savart integral over a spherical grid centered on the Earth. A scalar potential representation is used for the magnetic field due to the currents in the outer magnetosphere and solar wind, and the effects of the ground induction currents (GIC) are also included with a scalar potential by including the effects of an infinitely conducting sphere below the surface. Aside from the code’s ability to compute realistic magnetic field disturbances at individual magnetometers, it is possible to compile synthetic geomagnetic indices and synthetic global disturbance maps. The software is intended as a general-use tool and was built to be flexible so that it can be integrated with a wide variety of large-scale MI coupling models. The synthetic magnetogram model was built as post-processing software and has been parallelized using the message passing interface library. The inputs include: (a) ionospheric and magnetospheric currents (within an Earth-centered sphere of radius ~8 RE) and (b) the magnetic field on the surface of the same sphere, where the magnetic field effects of the ionospheric and GICs can safely be neglected. The radius of the sphere can be changed, as long as the sphere does not intersect with the Chapman-Ferraro (magnetopause) currents so that their relative effects can be separated from the other contributions. We will describe the model and show examples of the use of the code with a Rice Convection Model simulation of an idealized storm.
- Publication:
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AGU Fall Meeting Abstracts
- Pub Date:
- December 2009
- Bibcode:
- 2009AGUFMSM51A1312T
- Keywords:
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- 2753 MAGNETOSPHERIC PHYSICS / Numerical modeling;
- 2794 MAGNETOSPHERIC PHYSICS / Instruments and techniques