New model alternatives for improving the representation of the core magnetic field of Antarctica

• Published in: Antarctic Science
• Main Authors: Gaya-Piqué, L. R., Ravat, D., De Santis, A., Torta, J. M.
• Other Authors: Gaya-Piqué, L. R.; Istituto Nazionale di Geofisica e Vulcanologia, Sezione Roma2, Roma, Italia, Ravat, D.; Department of Geology 4324, Southern Illinois University Carbondale, Carbondale, IL 62901-4324, USA, De Santis, A.; Istituto Nazionale di Geofisica e Vulcanologia, Sezione Roma2, Roma, Italia, Torta, J. M.; Observatori de l’Ebre, CSIC - URL, Horta Alta 38, 43520 Roquetes, Spain, Istituto Nazionale di Geofisica e Vulcanologia, Sezione Roma2, Roma, Italia, Department of Geology 4324, Southern Illinois University Carbondale, Carbondale, IL 62901-4324, USA, Observatori de l’Ebre, CSIC - URL, Horta Alta 38, 43520 Roquetes, Spain
• Format: Article in Journal/Newspaper
• Language: English
• Published: Antarctic Science Ltd 2006
• Subjects: geomagnetic secular variation; IGRF; magnetic anomalies; spherical harmonics; 04. Solid Earth::04.05. Geomagnetism::04.05.03. Global and regional models; 04. Solid Earth::04.05. Geomagnetism::04.05.04. Magnetic anomalies; 04. Solid Earth::04.05. Geomagnetism::04.05.05. Main geomagnetic field; Antarctic; The Antarctic; Antarc*; Antarctic Science; Antarctica
• Online Access: http://hdl.handle.net/2122/3961; https://doi.org/10.1017/S0954102006000095

Use of the International Geomagnetic Reference Field Model (IGRF) to construct magnetic anomaly maps can lead to problems with the accurate determination of magnetic anomalies that are readily apparent at the edges of local or regional magnetic surveys carried out at different epochs. The situation is severe in areas like Antarctica, where ionospheric activity is intense and only a few ground magnetic observatories exist. This makes it difficult to properly separate from ionospheric variations the secular variation of the core magnetic field. We examine two alternatives to the piecewise-continuous IGRF core magnetic field in Antarctica for the last 45 years: the present global Comprehensive Model (CM4) and the new version of the Antarctic Reference Model (ARM). Both these continuous models are better at representing the secular variation in Antarctica than the IGRF. Therefore, their use is recommended for defining the crustal magnetic field of Antarctica (e.g. the next generation of the Antarctic Digital Magnetic Anomaly Map). Published 101-109 1.6. Osservazioni di geomagnetismo 3.4. Geomagnetismo 5.3. Banche dati di geomagnetismo, aeronomia, clima e ambiente JCR Journal reserved