The tides are often discussed, but to see them in action and how they impact Earth isn’t so easy to depict—until now.
The European Space Agency (ESA) published a new video this week that depicts the tides as they change around the world. But more importantly, it shows the magnetic field they create, which for the first time, has been mapped by the agency.
Every drop counts: the magnetic field generated by ocean tides is tiny and extremely difficult to measure.. but @esa #SwarmMission was up to the task! https://t.co/Z4VKOhiUN6 #EGU18 pic.twitter.com/UOGbaQH7LD
— ESA Earth Observation (@ESA_EO) April 10, 2018
Strong magnetic fields are easy to detect. But the tides create an exceedingly weak magnetic field that one researcher told BBC News is “about 20,000 times weaker” than the planet’s own magnetic pull.
To visualize the magnetic field, ESA scientists sent sensing technology into orbit in 2013 as part of its Swarm Mission featuring several satellites that took images of the planet. That data was then translated to a virtual Earth to show how tides create magnetic fields and how those magnetic fields change as the tide goes in and goes out.
But there’s more to the mission than simply understanding magnetic changes. The researchers said in a statement that the data collected shows how oceans flow “at all depths.” It could also shed light on climate change and how that might be affecting the tides, the oceans, and more broadly, the planet.
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The ESA video shows the tidal magnetic changes over a 24-hour period.
