Publication Date:
2017-04-04
Description:
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).
Description:
Published
Description:
101-109
Description:
1.6. Osservazioni di geomagnetismo
Description:
3.4. Geomagnetismo
Description:
5.3. Banche dati di geomagnetismo, aeronomia, clima e ambiente
Description:
JCR Journal
Description:
reserved
Keywords:
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
Repository Name:
Istituto Nazionale di Geofisica e Vulcanologia (INGV)
Type:
article
