Will These Stunningly Detailed New Maps of the Seabed Open the Oceans to Mining?
We know more about the topography of Mars than we do about the contours of the ocean floor on Earth. But now the Scripps Institution of Oceanography in San Diego has tapped data collected by satellites to create a map of the sea floor twice as detailed as existing versions.
The implications for industry and conservation are broad and possibly contradictory—the more we know about the deepest oceans, the greater the potential for both exploitation and protection.
“You could use this data to identify places to protect and preserve,” said David Sandwell, lead author of the Scripps study. On the other hand, the companies racing to scour our ocean floor for precious metals, oil, and gas could use this data to locate targets. Sandwell contends that they still need even higher resolution.
The mystery surrounding the missing Malaysian Airlines Flight 370 in the southern Indian Ocean raised public awareness of just how little we know of what lies beneath the water covering 70 percent of our planet. To date, we’ve only explored and mapped some 10 percent of the seas. In 2005, for instance, a submarine slammed into a seamount only a hundred feet below the surface near Guam that had never been included in navigational charts.
“It would take about 200 ship years to completely map the ocean floor in the resolution we like,” said Sandwell. “The most remote parts of the ocean, people don’t go there anymore, and a spot like Point Nemo—the most remote place from any coastline on the planet—no one has ever been there. An expedition there would cost $40,000 every day.”
Not any more. Traditionally, ships would send sound waves to the ocean floor to map its contours—a technique called acoustic bathymetry. Scripps researchers took decades of that data and overlaid it with gravity measurements of the ocean floor captured by a satellite called CryoSat-2 launched to measure Arctic sea ice.
“Between 1997 and 2010 there was no new data,” said Sandwell. “CryoSat-2 launched in 2010 and they leave the radar on over the ocean and operating in low resolution. That’s turned out to be a great technology for mapping the ocean surface topography.”
Every seamount and ridge on the ocean floor reveals itself in corollary bumps on the ocean surface, most no more than a centimeter in height, but still perceptible by remote sensing satellite technology.
That gives scientists new insights into climate change and tsunami prediction but also could open up vast new areas of the ocean to mining.
“Some of the highest resolution ocean mapping is motivated by human endeavors such as marine science research and deep sea mineral exploration,” said Jonathan Lowe, vice president of strategic development and exploration for Nautilus Minerals, a Canadian company that has pioneered deep-sea mining.
“The significant improvements to [the acoustic bathymetry] model made possible by the latest CryoSat data will help bridge the gap in knowledge between the unmapped and mapped seafloor.”
The Scripps team is also working with Google to supply the search giant with a high-resolution global bathymetry map to enhance the navigation potential of Google Earth.
“We care about investigating other planets like Mars, but we should care about our oceans—they’re as remote as Mars,” said Sandwell. “And there are climate implications from what’s on the seafloor, because currents and tides are affected, both of which absorb CO2. Much of the seafloor is basically unknown.”