The massive solar storms that set off last weekend’s spectacular northern lights also triggered significant compass movements in the ocean off Â鶹´«Ã½Ó³»Island and in the Atlantic, according to the University of Victoria.
Ocean Networks Canada, a UVic initiative that operates deep-sea observatories in the three oceans around the country, discovered the disturbances during quality-control checks. The network uses compasses to orient the instruments that measure ocean currents.
It recorded the temporary distortion of the Earth’s magnetic field on instrument platforms deployed as deep as 2.7 kilometres below the ocean surface.
Researchers said the magnetic disruptions were potentially some of the most remote recordings ever captured.
The most significant magnetic shift moved the direction of the compass within a range of plus-30 to minus-30 degrees and was recorded at a depth of 25 metres at the Folger Passage subsea site, which is part of the network’s Neptune cabled observatory off the coast of Â鶹´«Ã½Ó³»Island.
Scientists say geomagnetic disturbances can pose risks to power grids, satellite networks and navigation systems — and affect animals’ own navigational abilities.
Kate Moran, Ocean Networks Canada president and CEO, said the reach of data recordings in deep water shows the magnitude of the solar flare over the past weekend, and the data may be useful for better understanding the geographic extent and intensity of solar storms.
Alex Slonimer, a scientific data specialist, was completing a daily check on the data in late March when he first noticed an anomaly in the numbers.
He initially thought it was an earthquake, but the changes were lasting for too long and concurrently at different locations. “Then, I looked into whether it was a solar flare, as the sun has been active recently,” he said.
This past weekend’s much larger solar storm reinforced the observation, with the peaks in the compass headings closely correlated to the peaks in the visible activity in the aurora.
Justin Albert, professor of physics with UVic’s department of physics and astronomy, said Ocean Networks Canada’s network “might provide a very helpful additional window into the effects of solar activity on the Earth’s terrestrial magnetism,” adding 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.”
