Volcanic eruptions at the bottom of the sea are at the heart of how the Earth works, yet we know surprisingly little about them.
But now, thanks to a network of seafloor sensors connected to the internet, scientists are starting to get a glimpse of the fundamental processes that shape our planet.
This “ocean observatory” is situated atop an underwater mountain range off the coast from Oregon and Washington, and can measure everything from the rumbles of deep-sea earthquakes to the chemical burps of volcanic vents. And it just went online this month, The New York Times reported.
About 70% of the volcanism on Earth occurs underwater, yet it’s traditionally been hard to study, said Deborah Kelley, the University of Washington scientist who directs the US part of the observatory (Canada directs the other part).
Now, for the first time, “we can see how a volcano lives and breathes and impacts our planet,” Kelley told Business Insider, adding “It’s basically the internet on the seafloor.”
An observatory under the sea
The planet is crisscrossed by long underwater mountain ranges found at the boundary between tectonic plates, known as mid-ocean ridges. These zipperlike borders are formed when a rocky layer of the Earth’s crust known as the mantle heats up and forms molten rock, or magma, which pushes the seafloor up.
Until recently, the only way scientists could study these mysterious volcanic regions was by taking sporadic expeditions by boat, where they could capture only a glimpse of what was going on.
“We’ve been studying these problems for decades, but on a cruise-by-cruise basis,” Maya Tolstoy, a marine geophysicist at Columbia University’s Lamont-Doherty Earth Observatory, told Business Insider. “This is first time we have this breadth of data streaming live from the seafloor.”
The new observatory, known as the Ocean Observatories Initiative, provides an uninterrupted stream of data from the bottom of the ocean that is beamed to shore via a system of deep-sea cables and broadcast worldwide via the internet.
The observatory was the brainchild of University of Washington oceanographer John Delaney. It consists of two parts — Canada operates the northern part, and the US operates the southern one (funded by the National Science Foundation).
Forecasting an eruption
One of the exciting things scientists can do with this observatory is predict volcanic eruptions and monitor them while they’re occurring. Earthquakes tell scientists about how the ground is deforming, which can provide clues that there’s going to be an eruption, Tolstoy explained.
In fact, in April 2015, Tolstoy and some colleagues noticed a big uptick in the number of earthquakes at Axial seamount, an underwater volcano about 300 miles west of Oregon. They predicted that it would erupt very soon, and sure enough, it erupted two days later.
Several months later, Kelley and her colleagues went on an expedition to the site. When they arrived and mapped the seafloor with their instruments, they found a new lava flow more than 400 feet thick, right where they expected it to be.
The ability to predict volcanic eruptions could be especially useful on land, where they pose a major risk to human life and property.
Still, while forecasting eruptions is exciting, its just one of the ways scientists can use the observatory to peer into this unexplored realm that we know so little about.
And scientists aren’t the only ones who are interested in learning about the deep sea. According to Kelley, several countries have plans to mine the seafloor for rare metals like gold and silver, and pharmaceutical companies are interested in tapping the secrets of the microbes that live in superheated vents and can withstand extreme temperatures.
Life in the deep
Having better access to the deep ocean is also revealing some of the amazing biological communities that live there.
In the late 1970s, scientists discovered deep cracks in the Earth’s surface near mid-ocean ridges out of which burbled water heated by the planet’s core. We now know that these hydrothermal vents, as they’re called, are home to rich ecosystems of microbes, bottom-feeding crabs and other unusual creatures.
This overturned a long-held belief that all living creatures had to get their energy from the sun, as these microbes get their energy from the heat and chemicals in the Earth’s interior. This knowledge expands the range of environments where living things can survive, which increases the possibility that life exists in other parts of the universe.