Oceanic Magnetism and Earth's Magnetic Field
The ocean is a terrifying place (exhibit A), but it sure is fascinating. With so many mysteries hidden in its depths, it’s sometimes surprising that we know anything about this mass that covers 71% of our planet. For instance, have you ever heard of oceanic magnetism? Well, read on!
The European Space Agency’s Swarm mission is diving deeper into earth’s magnetic field and the source of our planet’s magnetism. We know that our magnetic field is the result of a superheated, liquid iron core. However, other factors such as magnetized rocks in the crust and the flow of our oceans could also affect the earth’s magnetism. You wouldn’t think of saltwater as being able to make a difference in the earth’s magnetism, but it does have a small effect.
How Does Oceanic Magnetism Work?
As ocean water flows through the earth’s magnetic field, it generates an electric current which, in turn, creates a magnetic signal. According to Nils Olsen from the Technical University of Denmark, it could give us an insight into understanding our changing climate. Since our oceans absorb heat from the air, it’s possible to track how this heat is being distributed and stored, especially at depths. Because Swarm is measuring this magnetic reaction from space via satellites, it can be difficult to get an accurate reading--but it's still possible! It could even help give us a better understanding of why the earth’s magnetic field is weakening.
Swarm’s satellites haven’t just been able to locate this magnetic field created by the ocean’s tides. They’ve also been able to capture images of the electrical nature of the earth’s upper mantle located deep below the ocean’s floor.
Understanding the Findings
What else have the Swarm satellites been able to bring to light? Nils Olsen from the Technical University of Denmark states that Swarm is being used to measure the magnetic signals of tides from the ocean’s surface right down to the seabed which can paint a picture of how the ocean flows at all depths around the globe. “In addition, because this tidal magnetic signal also induces a weak magnetic response deep under the seabed, these results will be used to learn more about the electrical properties of Earth’s lithosphere and upper mantle,” explained Olsen.
Learning more about the intricacies of our oceans and our planet is what fuels us here at Apex Magnets! If you’re like us and live for magnetic findings, check out our magnets in the news blog or subscribe to our monthly newsletter. You’ll also get access to exclusive deals and sales!