HR: 0830h
AN: GP31D-0768    [PDF]
TI: Modelling the Earth's Magnetic Field Using Wavelets' Frame.
AU: * Chambodut, A
EM: chambodu@ipgp.jussieu.fr
AF: Laboratoire de Geomagnetisme, Institut de Physique du Globe de Paris, 4, place jussieu, T24-25, Paris, 75252 France
AU: Mandea, M
EM: mioara@ipgp.jussieu.fr
AF: Laboratoire de Geomagnetisme, Institut de Physique du Globe de Paris, 4, place jussieu, T24-25, Paris, 75252 France
AU: Holschneider, M
EM: hols@math.uni-potsdam.de
AF: Applied and Industrial Mathematics, Universitat of Potsdam, Am Neuen Palais, 10, Potsdam, D- 14469 Germany
AB: A new representation of the main field on the sphere is developed, by choosing an approach which always makes a direct relation between the spherical harmonics (SH) and wavelets (Holschneider and {\it al.}, 2003). Our work is mainly the theoretical description of the wavelets on the sphere in order to use them in field modelling. Our first results in modelling the Earth's magnetic field from observatory data using the wavelet basis underlines the applicability of the method. The comparison with the SH models shows how well the wavelets describe the magnetic field on a global scale. The regional features of the field are also observed in this global representation. Some first results using magnetic satellite data are also presented. Once more, our attempt is to produce two representations, applying the SHA and wavelets to the same satellite dataset. The potential of wavelets to represent geomagnetic field considering an uneven distribution (observatories) or an even one (satellite measurements) is clearly schown.
DE: 1532 Reference fields (regional, global)
DE: 1545 Spatial variations (all harmonics and anomalies)
SC: Geomagnetism and Paleomagnetism [GP]
MN: 2003 Fall Meeting