Application of satellite magnetic observations for estimating near-surface magnetic anomalies
© The Society of Geomagnetism and Earth, Planetary and Space Sciences (SGEPSS); The Seismological Society of Japan; The Volcanological Society of Japan; The Geodetic Society of Japan; The Japanese Society for Planetary Sciences. 2004
Received: 12 January 2004
Accepted: 1 September 2004
Published: 20 June 2014
Regional to continental scale magnetic anomaly maps are becoming increasingly available from airborne, shipborne, and terrestrial surveys. Satellite data are commonly considered to fill the coverage gaps in regional compilations of these near-surface surveys. For the near-surface Antarctic magnetic anomaly map being produced by the Antarctic Digital Magnetic Anomaly Project (ADMAP), we show that near-surface magnetic anomaly estimation is greatly enhanced by the joint inversion of the near-surface data with Ørsted satellite observations compared to Magsat data that have order-of-magnitude greater measurement errors, albeit collected at much lower orbital altitudes. The CHAMP satellite is observing the geomagnetic field with the same measurement accuracy as the Ørsted mission, but at the lower orbital altitudes covered by Magsat. Hence, additional significant improvement in predicting near-surface magnetic anomalies can result as lithospheric magnetic anomaly data from the CHAMP mission become available. Our analysis also suggests that a further order-of-magnitude improvement in the accuracy of the magnetometer measurements at minimum orbital altitude may reveal considerable new insight into the magnetic properties of the lithosphere.