Regional to continental scale magnetic anomaly maps are becoming increasingly available from airborne, ship-borne, and terrestrial surveys. Satellite data are commonly considered to fill the coverage gaps in regional compi-lations 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 ?rsted satellite observations compared to Magsat data that have order-of-magnitude greater measurement errors, albeit collected at much lower orbital alti-tudes. The CHAMP satellite is observing the geomagnetic field with the same measurement accuracy as the ?rsted mission, but at the lower orbital altitudes covered by Magsat. Hence, additional significant improvement in predict-ing 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.
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