Oceanic magnetic fields

Amongst the many sources which contribute to the geomagnetic field the magnetic field generation due to ocean circulation is the most faintest. It has been recognized that ocean flow generates magnetic field through the process of motional induction. Most of them were theoretical predictions and/or observationally supported in a regional scale. Land based magnetic and electrical field measurements and undersea-cable voltage measurements were used to validate the predictions. Recent studies have highlighted the potential of high quality satellite magnetic data to be utilized to study the magnetic signal of ocean tides. Several attempts have been made to study the weaker and time invariant magnetic signals of ocean currents. The signals generated by the steady motion of highly conducting oceans are predicted to be on the order of several nT at the Earth's surface. The ocean circulation signal is well pronounced in the southern hemisphere, where the eastward motion can circulate without hitting continental landmass.


Prediction of the radial component of the oceanic magnetic field.

Ocean tidal dynamo identified in CHAMP satellite magnetic data