Researchers are calling for the creation of what amounts to international nature preserves on the ocean floor, as they warily watch efforts underway to mine the bottom of the sea.
A paper published in the journal Science last week calls on the International Seabed Authority—which awards mining contracts in international waters—to designate areas as protected habitat in order to counterbalance the negative effects mining operations could have on ocean life.
"We know that mining will be very damaging based on short-term studies, but we don't know what the long-term and large-scale consequences will be," said Lisa Wedding, a fellow at the Center for Ocean Solutions and co-author of the report.
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The ocean floor is a rich source of metals, including economically critical copper and gold, as well as rare-earth elements. Advocates of deep sea mining say the concentrations of minerals in the ocean are higher than on land, and that seabed mining may be less dangerous to both the environment and to people than land-based mining is.
But since humans have never mined the ocean floor before, researchers and activists say mining will likely have unforeseen effects that could be severe.
The International Seabed Authority is meeting until July 24 to consider questions about how the mining of the seafloor would be regulated, three of the study's authors said in a call with CNBC. The authority has awarded 26 contracts that allow companies and governments to explore patches of the seafloor for potential mining contracts, the study noted. The agency gave out 18 of those 26 contracts in the last four years. The authors of the paper take it as a sign that interest in deep-sea mining may be accelerating.
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One section of deep ocean—called the Clarion-Clipperton Fracture Zone—is roughly 80 percent the size of the contiguous United States, and exploration contracts have already been granted for an area that is 25 percent of that.
"This appears to be a really critical point in the discussion, because soon there is going to be a shift from exploration to exploitation," said Sarah Reiter, an ocean policy analyst at the Monterey Bay Aquarium and another co-author. "We were surprised; the general public doesn't know that this is going on."
Reiter said most of the ocean floor lies outside national jurisdictions, and therefore belongs to the "all of the citizens of the world"
"We have an opportunity to benefit from the resources, but we also have a responsibility," she said.
The paper says that seabed mining may cause "serious, unpredictable, and potentially irreversible damage" to portions of the seafloor. It says the authority and mining companies should set aside marine environments that share many of the same characteristics as those being mined, as a kind of hedge against that damage. A protected area can provide a safe haven for species that may be wiped out or harmed by mining in another, similar area.
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The report did not give specifics on how these recommendations should be implemented or what it might cost to put them in place.
"Our approach is a kind of middle ground between environmentalists who say we shouldn't mine the deep sea at all and the companies who say there won't be any effects at all," co-author Larry Crowder of Stanford University told CNBC. "It is likely that the decisions ISA will make over the next few weeks will have an impact on seabed mining over the next century."
Officials of the ISA didn't immediately respond to CNBC's request for comment.