Researchers at Scripps Institute Work With NASA and ESA to Create Oceanic Maps

It's been a buzz-worthy topic since it was unveiled in this week's issue of the journal Science, but the discoverers of the newly mapped bottom of the sea are not your typical explorers.

Published this week in the journal Science, researchers from the Scripps Institute of Oceanography at the University of California San Diego have released a gravity map constructed to show the topography, including seamounts and valleys, of the deepest depths of the world's oceans. As the oceans cover nearly 71% of the Earth's surface, it's an important addition to global mapping efforts in recent years, and it's thanks to two keen observers.

No, we're not talking about Marco Polo, Magellan, or their friends the Lewis and Clark Boys. We're talking about the European Space Agency's Cryosat-2 and NASA's Jason-1 satellites, whose gravity induced imaging devices allowed for the researchers to view what lies far beneath the surface of the oceans.

"The pull of gravity reflects the topography and tectonics of the seafloor" lead researcher of the study, David Sandwell says. The radar altimetry used by the satellites was able to allow for great precision in constructing a global marine gravity model-one that is twice as accurate as previous models created nearly two decades ago.

Combined with existing data, the new map reveals distinct details of undersea mountains, thousands of them, which rise more than a kilometer from the bottom of the ocean. And the researchers say that the new model gives geologists a new insight into the tectonics of the deep ocean trenches.

"The kinds of things you can see very clearly now are abyssal hills, which are the most common land form on the planet" Sandwell says.

And the implications of the new satellite-formed mapping system extend far beyond simple sea-ferrying applications. Previously unseen features on the map reveal continental connections between South America and Africa, conveying new theories about the separations of Pangea, and also show possibilities for unexplored abyssal ecosystems that could undoubtedly be home to dozens of undiscovered species.

With the collaborative efforts put forth by the ESA and NASA, the researchers hope to continue to explore what lies beneath the surface of Earth, from a distant view only achievable in space.

Co-author of the paper and project manager for the ESA's CryoSat, Richard Francis says that "Although CryoSat's primary mission is in the cryosphere, we knew as soon as we selected its orbit that it would be invaluable for marine geodesy, and this work proves the point."