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.

Other new uses for ocean mapping are at once promising and perplexing. The possibity of mining the seabed, for example, raises challenging questions: Where does one country end and another begin? Who does the deep ocean belong to, if anyone? And multibeam sonar can also be used to calculate specific numbers of fish. "Our data is controversial because it can be easily misused—and people's livelihoods are at stake," says Mayer, who has done work for Canada's Department of Fisheries and Oceans. Rightly applied, emerging data about the oceans' fish stocks could be used to help promote conservation and renewable resources.

Mayer, who spends a good deal of time as a sort of ocean mapping detective, has also helped decipher earthquake faults off the coast of California and dump sites off the coast of Oahu—complete with indentations where chunks of concrete from the old Honolulu hospital had been deposited. He has worked with Mobil Oil to help map a pipeline route and with the World Wildlife Fund to produce maps of potential marine sanctuaries. Mayer was also called in to study some apparent fault lines in Lake Ontario. A nearby nuclear reactor had people nervous about the potential for disaster. The mapping revealed that what people thought were fault lines were actually trails of fly ash left behind by the steamers that made their way across the lake in the 19th century.

Sometimes these techniques result in unexpected discoveries. Such as the British Freedom. Over the course of four decades, Canadian hydrographers had developed a safety and navigation map for the waters off the coast of Halifax. But the single-beam sonar systems had missed the 400-foot vessel. Sunk by a German submarine in 1945, the ship went down in about 150 feet of water—right in the middle of a major shipping lane. Her masts reached high enough to be a hazard to navigation.

The bathymetric maps Mayer produces reflect their Greek roots: bathos, meaning deep, and metria, meaning the process of measuring. Like some fantastical multicolor dream, the maps depict a world of mysterious pink peaks and deep yellow gullies, expanses of cerulean blues, emerald greens and reds the color of poppies. "To anyone used to looking at little numbers and lines," says Mayer, "this really is a profound experience, to see the ocean floor for the first time in three dimensions." The results seem as much art as science. But the goal is far more than colorful pictures.

The big challenge right now in the field of ocean mapping is keeping up with the torrent of data. An acronym for "sound navigation and ranging," sonar emits pulses of sound and then reads the depth as the pulses bounce back off the bottom. Multibeam sonar sends out a fan of beams that can measure 60 depths simultaneously, and the incoming data is enough to fill a single CD-ROM in just one hour. How do you manage such a volume—and how do you transform it into something people can use?

Enter Colin Ware and his flying mouse. A computer scientist also from Canada's University of New Brunswick, Ware specializes in data visualization techniques; he will head UNH's new Data Visualization Center, which will work in conjunction with C-COM. During the past decade, he has collaborated with Mayer to develop Fledermaus, a "fly-through" software program that does just what its name suggests. Holding the "flying mouse" in midair in front of the screen, viewers can use simple hand gestures to navigate through amazing on-screen underwater worlds. "It's like a video game," says Ware. "Except it has a purpose."

Fledermaus allows people to see sonar readings in a way they can understand. "Flat, hand-contoured paper charts have literally 99 percent of the data missing," says Ware. "Now you can look at the sea floor from any angle, poke in here to check the depth, zoom over there to look at something else." Had it not been for Mayer, Fledermaus might have gone the way of so many other academic projects—a brilliant paper that sits on a shelf. "But Larry came along," says Ware, "and saw the potential to make this into a usable tool to understand data."

Just last summer, the U.S. Secretary of the Interior Bruce Babbitt was featured in front-page news photos "Fledermaus-ing" his way through Lake Tahoe. Famous for its exceptionally clear water, the 105,000-acre lake was dubbed by Mark Twain as "the fairest sight the whole earth affords." But clarity has been diminishing recently at a rate of one foot each year—and no one knows why. In 1968, a 10-inch white dinner plate could be seen from a depth of 105 feet. In 1997, it could only be seen at 70 feet.

Until last year, the only bathymetry of Lake Tahoe were maps made in 1923, inadequate for today's level of scientific study. Which is why the USGS launched cruise IS-98. To orchestrate the project, they worked with Mayer, who applied state-of-the-art ocean mapping technology to the problem. Mayer coordinated the appropriate sonar system, hired a survey company and then spent a week at command central, a condo on the shores of Lake Tahoe. "Larry's the fellow who really pulls everything together," says Ware. "These survey ships cost many thousands of dollars per day. So you need somebody with logistical skills and organizational abilities—a sort of military commander."

Out on the water, the 26-foot Inland Surveyor, with an EM1000 sonar system attached to its bow, spent each day carefully "mowing the grass," sending sonar images back to the computers as the vessel moved steadily back and forth across the lake. Manning the computers, Mayer and USGS colleague Jim Gardner studied the data as it came in, cleaning it up and removing disturbances. When they were finished, the bottom of Lake Tahoe had been recorded in a stunning gallery of three-dimensional digital photographs. Some of these images are posted on the Lake Tahoe Data Clearinghouse Web site http://blt.wr.usgs.gov/. With the information provided by these maps, scientists now have a better foundation from which to tackle the problem of diminishing water clarity.

While Mayer studies the topography of the ocean bottom, Laurence "Laurie" Linnett, an electrical engineer from Heriot-Watt University in Edinburgh, Scotland, uses sonar to examine the makeup of the sea's subsurface, up to 60 feet below the ocean floor. Linnett, who will move across the Atlantic to join UNH's C-COM team, is an expert in signal processing—untangling the complexity of sound waves. He specializes in image analysis and synthesis, extracting information from sonar images.

"Imagine you were planning a garden in your back yard," he says. "You need to dig but want to avoid large boulders." This is precisely the dilemma faced by companies such as Simplex, in Portsmouth, N.H., which makes fiber-optic cable and lays it down across thousands of miles of ocean floor. They need to know if they'll be digging in mud or sand, silt or clay. The underwater sea plows used to lay cable are expensive—and can break if they run into a boulder. Accurate information about the composition of the ocean floor can save thousands of dollars.

Or suppose an oil company is interested in avoiding the expense of broken lines. One software program Linnett designed will detect potential weak spots in an underwater pipeline, creating images and pinpointing specific geographic locations so engineers can find and fix the problem—in a fraction of the time it used to require.

Linnett's work has countless commercial applications, and he has worked with dozens of the world's largest companies. But for all the practical implications of his research, Linnett's primary goal is ever-improving data. "We are one of the only groups in the world doing this sort of work," he says. "We are developing new techniques for advanced sonar instruments that will build our vocabulary to communicate with the seabed."

For the past decade, Mayer and Linnett have been working on opposite sides of the Atlantic, developing different layers of an "information cake" about the ocean floor. At UNH, this research will finally come together in one place. The Jerry Chase Ocean Engineering Laboratory at UNH, home to some of the largest test tanks in New England, provides the ideal setting for developing new sonar equipment. And, with the expertise of Colin Ware, the increasing flood of sonar data will be integrated and presented in new ways that will allow viewers to peel back the layers, choosing data to "fly through" and examine. Together, these three researchers will lead C-COM in the exploration of new avenues and uses for ocean mapping.

UNH's C-COM team members are pioneers on the edge of what many consider the last great frontier. "We know more about the moon than we know about our own planet beneath the sea," says Linnett. "It's actually far easier to explore the moon. The deep-sea environment is harsh: several thousand feet down the pressure is intense—plus there are some pretty strange animals down there."

Though they rarely get their feet wet, UNH's "astronauts of the sea" will help to create and decipher images as mysterious and significant as the first handfuls of moondust picked up by the early space explorers. "Sometimes you see things," says Linnett, "and for a few minutes or hours, you're the only person in the world who's ever seen it." Thanks to UNH's new ocean mapping team, the rest of us, too, will be able to explore the mysteries of the deep—sailing through multicolored worlds on the wings of a flying mouse. ~

Suki Casanave '86G is a writer for the College of Engineering and Physical Sciences. She also writes for regional and national publications. She earned a graduate degree in literature from UNH.