HR: 0800h
AN: SA11A-0299 [Abstracts]
TI: Storm-enhanced neutral wind dynamo effects on the Earth's magnetic field
AU: * Woodfield, E E
EM: Emma.Woodfield@lancaster.ac.uk
AF: University of Liverpool, Dept of Earth and Ocean Sciences
4 Brownlow Street, Liverpool, L69 3GP, United Kingdom
AU: Aruliah, A
AF: University College London, Atmospheric Physics Laboratory
Dept of Physics and Astronomy
Gower Street, London, WC1E 6BT, United Kingdom
AU: Holme, R
AF: University of Liverpool, Dept of Earth and Ocean Sciences
4 Brownlow Street, Liverpool, L69 3GP, United Kingdom
AU: Millward, G
AF: University of Colorado, Laboratory for Atmospheric and Space Physics, Boulder, CA WC1E
6BT, United States
AB:
The neutral wind dynamo driven currents in the E-region of the ionosphere are one of many sources contributing
to the Earth's overall magnetic field. Characterisation of the various sources is a vital step in understanding the
Earth's whole magnetic environment from the core to the magnetosphere. Storm activity increases the kinetic
energy in the neutral atmosphere and the enhanced motion decays gradually. This has a knock-on effect on the
magnetic field at the ground at low to mid-latitudes. We have used the Coupled Thermosphere Ionosphere
Plasmasphere model (CTIP) to assess the impact of the neutral particle inertia on the magnetic field. Our
motivation is to quantify the magnitude of this effect such that it can be accounted for in geomagnetic field
modelling. Our initial results using an artificial storm indicated a small (of the order of 10 nT) and long-lived (a
few days) elevation in the magnetic field originating from this source. This has been extended to analyse the
model output during a real storm event.
DE: 1599 General or miscellaneous
DE: 2409 Current systems (2721)
DE: 2415 Equatorial ionosphere
DE: 2788 Magnetic storms and substorms (7954)
SC: SPA-Aeronomy [SA]
MN: 2007 Fall Meeting