Phys.org May 16, 2024
The powerful solar storm driving the aurora borealis over global skies last weekend was also triggering the movement of compasses deep in the ocean, as revealed by Ocean Networks Canada (ONC), a University of Victoria initiative. The most significant magnetic shift moved the direction of the compass within a range of +30 to -30 degrees and was recorded at a depth of 25 meters at the Folger Passage subsea site, which is part of the ONC NEPTUNE cabled observatory off the coast of Vancouver Island. ONC’s subsea observatories on the west and east coasts of Canada recorded the temporary distortion of the Earth’s magnetic field on instrument platforms deployed as deep as 2.7 kilometers under the ocean surface, potentially some of the most remote recordings ever captured. The discovery of these solar storm magnetic disturbances happened during data quality control checks. According to the University of Victoria’s Department of Physics and Astronomy the next two years will be the peak of the 11-year solar cycle. After a decade of relative inactivity, aurora events like this past weekend are likely to become more frequent over the next couple of years, although solar variability makes precise prediction of such events impossible. ONC’s network might provide a very helpful additional window into the effects of solar activity on the Earth’s terrestrial magnetism… read more.
Compass data captured by ONC’s major cabled subsea observatories VENUS and NEPTUNE off Vancouver Island… Credit: Ocean Networks Canada