When most people think of exploration in the 21st century, they picture telescopes, space shuttles and unmanned rovers. But there’s plenty left to explore here on Earth, in the oceans that cover more than two-thirds of the planet’s surface. In fact, 95 percent of this region remains unseen by humans, according to the National Oceanic and Atmospheric Administration.

These uncharted waters have long fascinated Larry Mayer, a professor of earth science and ocean engineering at UNH. Over the past three decades, he has participated in more than 90 research cruises, logging a total of over six years at sea. “The ocean is full of all kinds of mysteries once you start looking,” says Mayer, the founding director of UNH’s Center for Coastal and Ocean Mapping.  

And Mayer’s research has also yielded some answers with important economic and environmental implications. Since 2003, he’s led or co-led nine expeditions in the Arctic and Gulf of Alaska, mapping previously unexplored sections of the seafloor in support of potential U.S. rights under the Law of the Sea Treaty. This 30-year-old agreement allows each nation to establish sovereign rights over the portion of its continental shelf that extends beyond a 200-nautical-mile exclusive economic zone. To do so, however, the country must determine the boundaries of its extended continental shelf by delineating the shape of the seafloor and the thickness of its sediment.  

Mayer’s team is finding that the U.S. extended continental shelf reaches much further than expected, potentially giving the country access to significant oil, gas and mineral deposits buried offshore. Though the Senate has yet to ratify the Law of the Sea Treaty, Mayer is optimistic that the United States eventually will become a party to the agreement. “It’s many trillions of dollars we’re talking about, and also the ability and responsibility to protect large areas. It’s a matter of tremendous national concern and value.” 

To generate a view of the seafloor, Mayer’s team uses multibeam sonar technology. Developed in the 1980s, this tool sends out hundreds of acoustic pulses in a fan-shaped swath. The returning signals are translated into a three-dimensional picture using software in the laboratory. “We’ve never really had a chance to look at such a large area with such a high resolution,” says Mayer, who posts his findings online and sends them to the National Geophysical Data Center. “Many papers will come out of this data. It’s a legacy for generations.

Mayer and his colleagues have detected previously unknown channels, craters, and scour marks on the seafloor. During their 2003 Arctic expedition, they discovered a mountain taller than Mount Washington. They named it the Healy Seamount after their 430-foot Coast Guard Cutter. “In an area that maps showed was flat, to have a 10,000-foot mountain appear is quite a surprise — and important, especially if you know it’s an area where submarines sometimes transit.”

Near the North Pole last year, the research team found hundreds of miles of seafloor arranged in a chaotic fashion, with bumps and depressions created by something moving in an irregular way. Mayer speculates that this unique formation may have resulted from the long-ago impact of a meteorite.  

Mayer also has gotten a firsthand look at the effects of climate change. “Because of its sensitivity, the Arctic is the canary in the coal mine when it comes to global warming,” he explains. “In 2007, we saw very clear evidence of the break-up of the permanent icepack. This year broke the 2007 record and we saw hardly any ice at all. It was unbelievable.” In fact, his team traveled some 420 miles further north than usual before encountering the edge of the icepack. This melting could speed up climate change and affect weather trends worldwide. It could also make it easier to drill for undersea resources, Mayer says, heightening commercial interest in the region.  

But the possibility of deep-water drilling in the Arctic raisesconcerns about how best to protect a cold, icy environment that lacks the infrastructure to deal with oil spills. Instead of the prescriptive regulations adopted by the United States, Mayer advocates a performance-based approach that focuses on risk analysis. As leader of the National Resource Council’s committee to study the effects of the Deepwater Horizon oil spill on the ecosystems of the Gulf of Mexico, “I’m very aware of the impacts of that spill, and I’m very aware of how lucky we were,” he says. “It could have been much worse. A comparable spill in the Arctic would be absolutely catastrophic.” Though he travels to the Arctic to uncover what’s hidden beneath water and ice, Mayer says he also finds peace and beauty there. “On a sunny day, it’s absolutely gorgeous if you’re on the ice. The forms of the ice, the sun reflecting off the ice, it’s like sculpture changing all the time. You get some interesting colors, too, mostly blues from light penetrating the ice. And spectacular sunsets, if you’re there late enough in the year that the sun sets.”

By Sonia Scherr

First published by UNH Research