Abstract
Following the call for candidates for the 10th generation IGRF, we produced and submitted three main field and three secular variation candidate models. The candidates are derived from parent models which use a standard quadratic parameterisation in time of the internal Gauss coefficients. External magnetospheric fields are represented by combined parameterisations in Solar Magnetic (SM) and in Geocentric Solar Magnetospheric (GSM) coordinates. Apart from the daily and annual variations caused by these external fields, the model also accounts for induction by Earth rotation in a non-axial external field. The uncertainties of our candidates are estimated by comparing independent models from CHAMP and Èrsted data. The root mean square errors of our main field candidates, for the internal field to spherical harmonic degree 13, are estimated to be less than 8 nT at the Earth’s surface. Our secular variation candidates are estimated to have root mean square uncertainties of 12 nT per year. A hind-cast analysis of the geomagnetic field for earlier epochs shows that our secular acceleration estimates from post-2000 satellite data are inconsistent with pre-2000 acceleration in the field. This could confirm earlier reports of a jerk around 2000.0, with a genuine change in the secular acceleration.
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Lesur, V., S. Macmillan, and A. Thomson, A magnetic field model with daily variations of the magnetospheric field and its induced counterpart in 2001, Geophys. J. Int., 160, 79–88, 2005.
Lühr, H., M. Rother, S. Maus, W. Mai, and D. Cooke, The diamagnetic effect of the equatorial Appleton anomaly: Its characteristics and impact on geomagnetic field modelling, Geophys. Res. Lett., 30, 1906, doi:10.1029/2003GL017407, 2003.
Mandea, M., E. Bellanger, and J.-L. Le Mouël, A geomagnetic jerk for the end of the 20th century?, Earth Planet. Sci. Lett., 183, 369–373, 2000.
Maus, S., H. Lühr, G. Balasis, M. Rother, and M. Mandea, Introducing POMME, the POtsdam Magnetic Model of the Earth, in CHAMP Mission Results II, pp. 293–298, Springer Berlin, 2005a.
Maus, S. and H. Lühr, Signature of the quiet-time magnetospheric magnetic field and its electromagnetic induction in the rotating Earth, Geophys. J. Int., 2005b (in press).
Maus, S. and P. Weidelt, Separating the magnetospheric disturbance magnetic field into external and transient internal contributions using a 1D conductivity model of the Earth, Geophys. Res. Lett., 31, L12,614, 10.1029/2004GL020,232, 2004.
Maus, S., S. Macmillan, F. Lowes, and T. Bondar, Evaluation of candidate geomagnetic field models for the 10th generation of IGRF, Earth Planets Space, 56, this issue, 1173–1181, 2005c.
Maus, S., M. Rother, K. Hemant, H. Luehr, C. Stolle, A. Kuvshinov, and N. Olsen, Earth’s crustal magnetic field determined to spherical harmonic degree 90 from CHAMP satellite measurements, Geophys. J. Int., 2005d (submitted).
Maus, S. and A. Kuvshinov, Ocean tidal signals in observatory and satellite magnetic measurements, Geophys. Res. Lett., 31, L15313, 10.1029/2004GL020090, 2004.
Olsen, N., A model of the geomagnetic field and its secular variation for epoch 2000 estimated from Èrsted data, Geophys. J. Int., 149, 454–462, 2002.
Olsen, N., New parameterization of external and induced fields for geomagnetic field modeling, Geophysical Research Abstracts Volume 6, Abstracts of the Contributions of the EGU General Assembly, Nice, France, 2004.
Olsen, N., T. J. Sabaka, and F. Lowes, New parameterization of external and induced fields in geomagnetic field modeling, and a candidate model for IGRF 2005, Earth Planets Space, 57, this issue, 1141–1149, 2005.
Ritter, P., H. Lühr, A. Viljanen, and S. Maus, High-latitude ionospheric currents during very quiet times: their characteristics and predictability, Annales Geophysicae, 22, 2001–2014, 2004.
Sabaka, T., N. Olsen, and M. E. Purucker, Extending comprehensive models of the Earth’s magnetic field with Èrsted and CHAMP data, Geophys. J. Int., 159, 521–547, 2004.
Tyler, R., S. Maus, and H. Lühr, Satellite observations of magnetic fields due to ocean tidal flow, Science, 299, 239–241, 2003.
Utada, H., H. Koyama, H. Shimizu, and A. D. Chave, A semi-global reference model for electrical conductivity in the mid-mantle beneath the north Pacific region, Geophys. Res. Lett., 30, 10.1029/2002GL016092, 2003.
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Maus, S., McLean, S., Dater, D. et al. NGDC/GFZ candidate models for the 10th generation International Geomagnetic Reference Field. Earth Planet Sp 57, 1151–1156 (2005). https://doi.org/10.1186/BF03351898
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DOI: https://doi.org/10.1186/BF03351898