Portraits of the Deep
Ocean mapping is unveiling the deepest secrets of the sea, and UNH will soon be educating a new generation of experts

The floor of the North Atlantic Ocean is unveiled in this computerized 3-D ocean mapping image. Nova Scotia is upper right; the caribbean is lower left. Eastern U.S. and Canada are at top, shaded green and brown.

When Sir John Murray shoved off from the shores of Scotland's famous Loch Ness in 1897, he took with him a lead weight, a notebook—and a fellow to row the boat. While his assistant held the craft on course, Murray pedaled. The bicycle wheel contraption he'd devised released the weight, dropping it to the bottom of the loch, then reeling it back in. Counting each revolution, Murray calculated the depth, then recorded the measurement in his notebook. When he was finished, the pair rowed another 10 feet and repeated the process.

By this painstaking method, working his way across and then down the entire 25-mile length of the loch, Murray conducted the first hydrographic survey of the bottom of the world's most famous loch. He was also, one assumes, in top-notch shape after weeks and weeks of pedaling. The map he created consisted of individual depth measurements connected by contour lines—the spaces between filled only by the viewer's imaginings.

A century later, a multibeam sonar, attached to a motor-powered boat, retraced Murray's route, completing the venture in less than a day and producing a stunning three-dimensional color image of the loch's underwater topography. Even the legendary Loch Ness monster would have had a hard time hiding from the thorough sweep of this sonar search, which revealed every rock and ridge and six-inch sand bar. "This is a revolutionary way of seeing the ocean floor," says Larry Mayer, a pioneer in the field of ocean mapping. "I liken it to the change that took place when people could see the earth with satellite images for the first time."

The transformation has been swift. Until 50 years ago, hydrographers used the lead weight method and were able to take perhaps 10 readings an hour. When the depth sounder (a single-beam sonar) was invented during World War II, it was suddenly possible to take 20,000 readings an hour, but the results were not much better. For the past decade, instead of this connect-the-dots approach to ocean mapping, it's been possible to get what scientists call "full-bottom coverage." Today's multibeam sonars take up to 15 million readings an hour, depicting every contour. And they reveal a whole new world.

The University of New Hampshire will soon be the leading university from which to explore this new world. When Mayer arrives in Durham next year, he will help launch two new interlocking centers—the Joint Hydrographic Center (JHC) and the Center for Coastal and Ocean Mapping (C-COM). The new centers provide a two-pronged opportunity available nowhere else in the country: training in hydrography—plotting the ocean's shallowest points for navigation purposes—and education in the broader applications of ocean mapping, a complex world of three-dimensional detail revealed by multibeam sonar technology.

Funded with an initial $2 million secured by U.S. Senator Judd Gregg (R-N.H.), together with private and corporate donations, the JHC is modeled after another successful UNH-National Oceanic and Atmospheric Administration (NOAA) partnership devoted to coastal studies. The new hydrographic center will be jointly directed, by Mayer, who comes to UNH from Canada's University of New Brunswick, and by NOAA's Capt. Andy Armstrong, chief of the hydrographic surveys division.

Hydrography has long been the province of NOAA, the Navy and the U.S. Army Corps of Engineers. Training their own employees, they produce the hydrographic survey maps necessary to carry out their missions—from national security to the dredging of ports and river bottoms. With the founding of the University's JHC, the U.S. will finally have an academic center for training the next generation of hydrographers.

And none too soon, according to Armstrong. "There is a great shortage of trained hydrographers in this country," he notes. "And we have a huge job to do." NOAA's 1,000 hydrographic charts cover 3.5 million square miles of coastal waters. Many of the soundings on these charts, determined with lead lines or rudimentary depth sounders, are now more than 50 years old. NOAA has undertaken the daunting task of updating this information. The first 40,000 square miles alone—those waters deemed most critical—will take two decades to complete.

UNH's hydrography center, which will accept its first graduate students this fall through the ocean engineering program, is focused primarily on training. "But the development of new technologies through C-COM can greatly speed our updating efforts," says Armstrong. The two centers build on UNH's impressive ocean engineering programs, according to Roy Torbert, dean of UNH's College of Engineering and Physical Sciences. "And this new thrust in ocean mapping has tremendous potential for exciting new projects for our students and for world-class research," he says. "It will also provide major economic opportunities for companies in New Hampshire and New England."

Mayer sees UNH as a world leader in ocean mapping. "Our focus at C-COM is the development of new uses for this technology," he says. Along with creating more detailed hydrographic charts for navigation, the technology already is being used to help companies lay trans-atlantic cable and to determine pipeline routes. Accurate bottom surveys are also needed to determine the best locations for anchoring aquaculture fish cages, oil derricks—and even off-shore floating airports, a concept being explored by the Japanese, as well as by the U.S. military.

Page: 1 2 3 Next >

 Easy to print version

blog comments powered by Disqus