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Rogue Waves Challenge Ocean Theorists Vol.1 No.4 Fall 2004 A message from Rogue waves challenge the Dean . ocean theorists Dear Friends of the Ocean, Long thought to exist only in seafarers’ “fish stories,” rogue waves on the order of I am pleased to one hundred feet tall have been detected in recent years by radars mounted on North Sea announce that we have oil platforms. Now, a global census by the European Space Agency has established these been granted an monster waves as a relatively common phenomenon. opportunity to expand In a project dubbed MaxWave, European scientists recently assembled some 30,000 our research in critical satellite radar “imagettes” to get an image of the world ocean over a period of about three areas of fisheries weeks in early 2001. Within that short period, they identified at least ten rogue waves science and oceanography and to support with heights of 25 meters or more. the training of a new cohort of graduate More than 100 ships are sunk every year, and up to 10% of those are supertankers students through the University of and container ships more than 200 meters in length. It’s impossible to investigate such Massachusetts Graduate School of accidents to the same extent as, say, airline disasters, and most have been chalked up to Marine Sciences and Technology. We “severe weather.” Rogue waves are now implicated in many of those sinkings. have, working with the Massachusetts To better understand the phenomenon of rogue waves and its implications, we talked Marine Fisheries Institute, received funds to two scientists on the faculty of the UMass to embark on an ambitious program of Marine Graduate School. Steve Pennell is fishery and related oceanographic Professor of Mathematical Sciences at research. About $300,000 will be used UMass Lowell. His related work includes to fund graduate student stipends to modeling wave-wave interactions and conduct research relevant to the program. investigating the surface expressions of The program focuses its research on internal ocean waves. Wendell Brown is scallops, groundfish, lobsters, and Professor of Oceanography and Faculty oceanographic modeling of Georges Bank Chair at SMAST/UMassD. An observational and the Gulf of Maine. oceanographer, his research has ranged over Our very successful video surveys of a number of ocean basins in the Western the spatial and size-specific abundance Hemisphere, but has focused particularly on of scallops on the continental shelf will the regional Gulf of Maine, where studies Wave modeler Steve Pennell, UMass Lowell, continue under the new program. The of the internal tide have been one of his and oceanographer Wendell Brown, UMass video surveys will be used as a baseline continuing interests. Dartmouth. to calculate the fishing power and catchability of various types of scallop UMM: How are these rogue waves similar Sea floor topography may play some role in gear, and the effect of fishing gear on to or different from the solitary waves you the generation of rogue waves, but it appears habitat and on benthic fauna. We will have studied and modeled? that near-surface currents and wind play also continue our studies of tagged Pennell: Rogue waves are similar to solitary more important roles. scallops on the continental shelf to waves in that both are isolated mounds of Brown: Some internal solitary waves, or estimate growth, migration, and mortality water rather than wave trains, both can be ISWs, result from highly nonlinear distortion rates. Finally, laboratory studies of huge, and both are described by nonlinear of much smaller internal tidal waves, which scallop biology—using specimens equations. The main difference is that rogue in turn are generated by tidal currents contributed by the commercial fleet—will waves are surface waves, whereas oceanic flowing over steep bottom topography. The be conducted to enhance stock solitary waves are internal waves. The resulting internal solitary waves can have assessment estimates. generation mechanisms also appear to be underwater amplitudes of 200 meters (in In the groundfish arena, an innovative different. Oceanic internal solitary waves the South China Sea, for example). While Fishery Management Decision Support are usually generated by tidal flow over an these ISWs are not nearly as energetic as System is already under development. underwater sill, as at the Strait of Gibraltar. Continued on page 2 Continued on page 3 UMASS MARINE is published by the University of Massachusetts Intercampus Graduate School of Marine Sciences and Technology, Office of the Dean, Brian J. Rothschild, 706 South Rodney French Blvd., New Bedford, MA 02744-1221. Information and submissions: [email protected] • 508-910-6347 Editor: Frank Smith Production: Dianne Rittmuller best time, and I wish there were more hours Dean’s Message, continued from page 1 Introducing ... in each day to fit in everything.” Operations research theory will be incorporated into the system to enable • • • formulation of decision rules that take into account multiple species interactions. We Students Adrienne Pappal has always known are also developing an acousto-optic fish It was more than 20 years ago that what she wanted to do. “I never dreamed assessment array for Georges Bank. The Deborah Cobb finished her bachelor’s degree to be an astronaut or superstar. I still keep array will be used to enumerate size and in Biology at East Carolina University. She the pictures from childhood that I drew of species-specific fish abundance on the had already started graduate school when myself in a vast Crayola sea. There is Bank. Fishing-gear engineering studies love intervened. She got married, moved something so compelling about that great will modify trawls to improve their to New England, and started a family. As expanse of water.” selectivity to separate target and non- Deborah puts it, “I put graduate school on Her continuing fascination with the target species to minimize waste and hold for a few years; a few years turned ocean eventually led Adrienne to enroll at reduce unwanted bycatch. out to be a couple of decades.” the University of New Hampshire (UNH) in The lobster fishery will be the focus In 2002, with one child in a doctoral 1997 to study Marine and Freshwater of a three-part research effort. Lobster Biology. “As an undergraduate,” she says, stock assessment will be enhanced by “I jumped at any opportunity to expand my calibrating ventless traps using scuba exposure to the field of marine science.” observation, and migrations will be Such opportunities appeared studied to better identify stock structure. first in the form of summer field At left, Deborah Cobb. The lobster disease problem will also be marine science programs at the Below: Deborah immersed in defined and evaluated, and studies of Shoals Marine Lab, jointly operated her work. Buzzards Bay water will help determine by UNH and Cornell University. the role of water chemistry in declines in “These were my first real field lobster abundance. experiences,” says Adrienne, “and Finally, the new program will also I was hooked.” bolster our Georges Bank/Gulf of Maine From that point, Adrienne oceanographic modeling research. The moved into teaching, sharing her Georges Bank/Gulf of Maine region is the program, one in enthusiasm for marine science breadbasket for coastal New England, and college, one in with fellow college students as we are bringing more and more model high school, and teaching assistant, with the public products into near real time. one in middle at the NH Seacoast Science Stay tuned to the UMass Marine school, Deborah Center, and with school children newsletter and to our website picked up where aboard the NH Sea Grant Floating www.umassmarine.net to follow the she left off. While Lab, a series of mini-research progress of these exciting research still teaching part- cruises, whereon the children efforts. time at Concord become the researchers. Academy, she enrolled part-time in the Adrienne’s final semester as an - Brian Rothschild, Dean UMass Marine Graduate School on the undergraduate was spent in New Zealand Boston campus, studying under Professor through the EcoQuest program, where she Robert Chen. studied marine sciences and conducted professor so I can teach others about the Deborah’s thesis research centers on independent research. “There, I was wonders of the ocean. If I can touch one monitoring bacterial levels in the Pine Tree challenged in every way,” she reports, “from life to get involved and excited about the Brook in Milton before, during, and after a scaling mountains to spending hours sorting ocean, then I’ll have reached my goal.” § water quality improvement project by the samples. But the rewards were great.” Neponset River Watershed Association. The At SMAST, Adrienne is pursuing her Adrienne Pappal collects samples on the Pine Tree Brook borders Milton High School, master’s degree in Living Marine Resources shore of Mt. Hope Bay. a convenience for the school’s Science and Management through the Environmental Science students who are UMass Intercampus Marine Graduate involved in Deborah’s sample collection, School. With advisor Dan MacDonald, she processing, and data interpretation. is researching the community structure of “Ultimately, I would like people to be fishes in varied intertidal habitats. more educated about coastal processes and “I am particularly interested in the their effects upon our quality of life,” distribution patterns of juvenile winter Deborah says. “Hopefully, with education, flounder, as this species is in decline in New change will come and our coastal areas will England estuaries. I hope to continue my start to rebound.” research this fall with laboratory study of A part-time student for her first three habitat preferences of juvenile winter semesters at UMass, Deborah will be a flounder.” fulltime student this fall and part of the Characteristically, Adrienne also has Watershed-Integrated Sciences Partnership plans for the longer term.
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