Thursday, October 23, 2014

URI oceanographer charting the dynamics of underwater ocean storms

D. Randolph Watts named Fellow of American Meteorological Society

NARRAGANSETT, R.I. – October 16, 2014 – When D. Randolph Watts joined the University of Rhode Island faculty in 1974 to study ocean circulation and eddies, there were few oceanographic instruments capable of capturing the data he sought. So he began developing devices that have revolutionized the discipline, devices that are now used by scientists around the world.

For his contributions to the study of physical oceanography, Watts was recently named one of 28 new fellows of the American Meteorological Society. Only two of every 1,000 members of the society are honored as fellows. His induction will take place in January.

“I feel very honored to have been selected,” said Watts, a professor at the URI Graduate School of Oceanography. 

While it may sound surprising that an oceanographer would be recognized by a meteorological society, Watts said that the two disciplines have strong links.

“The ocean exerts profound influences on the atmosphere,” he said. “The ocean is a giant reservoir of heat and carbon dioxide that exchanges with the atmosphere and influences climate in important ways.”

Watts has long been interested in ocean eddies, which he says are the underwater equivalent of storms in the atmosphere. They cause the strongest variations in ocean currents, and they profoundly control where and how deeply the ocean currents flow. Eddies determine how the ocean carries heat from the equator to the poles and how the ocean can store carbon dioxide from the earth’s atmosphere.

Throughout his career, Watts has spent about one month each year aboard a research ship somewhere around the world, from the waters off Antarctica or Japan to New Zealand and Chile. That means more than three years of his life has been spent at sea.

“I’ve found it exciting and refreshing in those month-long intervals to be away from meetings and other distractions,” he said. “It allows me to be very focused on the task at hand.”

At sea he works 12-hour shifts with his team research launching and recovering oceanographic instruments that will help him diagnose the changing temperatures and motions of water via ocean eddies. The arrays of instruments sit on the sea floor gathering data and may not be recovered for several years. 

“Eddies are typically about 100 kilometers across, and they’re everywhere in the oceans,” Watts said. “They’re especially energetic in the Gulf Stream and in the Gulf of Mexico Loop Current and encircling Antarctica. These currents have excess energy that they release by forming huge meanders and underwater storms called eddies. Eddies redistribute heat and momentum so fundamentally that the ocean temperature structure and currents would be inconceivably different without eddies.”

To study these currents, Watts developed a pressure inverted echo sounder that uses acoustic signals to measure the patterns of warm and cool water meandering in the eddies. The device sends an acoustic signal from the seafloor to the sea surface and back. Because sound travels at different speeds depending on the temperature, the speed that the signal travels allows him to learn what is taking place in the ocean.

“It’s been a great opportunity to have the right suite of measurements and the right team of people working together to make a unique contribution to science,” said Watts, noting that colleague Karen Tracey has worked with him since 1980 and has played an essential role in his research team. “We’ve learned a great deal about how eddies grow and how they move water and heat across them. That was an unexplored field when we started looking.”

Watts said he is far from finished with his research. He is looking forward to launching a new experiment in the Pacific off Antarctica where ocean currents are carrying heat to the base of rapidly melting glaciers. And he calls a recent request for funding “his best proposal ever,” one he hopes will begin a new project in the Argentina Basin, where the warm southward-flowing Brazil Current meets the cold Antarctic Circumpolar Current, and eddies exchange and fundamentally alter the water properties. 

“Nature has served us up a beautiful test crucible in the Argentine Basin. The observational capabilities and numerical models and theoretical ideas have matured to where we can really make progress to understand the processes there,” Watts said.

His greatest worry, however, is the rapid change taking place in the earth’s climate. He attended the recent climate march in New York City to show his support for taking steps now to reduce its effects.

“I’m very concerned how amazingly fast climate change is happening now and how urgent it is to do everything we can to slow it down,” he said. “There will be serious disruptions to our lives and environment, even in the coming 10 or 20 years. Man and the environment and technology have the chance of adapting to the changes, if we can just slow them down. The amazing affordability already today of solar and wind energy gives me reason for optimism if we act now.”