Sea Tidally Induced Variations of the Earth's Magnetic Field (Leakage of Current from the Atlantic)

INTEREST has recently revived in the possible effects of the sea tides on the Earth's magnetic field; modern instrumentation has made direct measurement possible 1,2 . Malin 3 has shown how the semi-diurnal lunar variation arising from the ocean and sea tides may be inferred from the complete lunar variation observed at any given station. The time seems appropriate to begin work on detailed theoretical models taking into account the topography of the coastline. Here we continue work 4,5 specifically aimed at understanding the magnitudes and distributions of ocean and sea tidally induced magnetic fields over the British Isles.