PBS Spotlights UT Global Warming Research

KNOXVILLE — An Arctic research cruise conducted by University of Tennessee faculty and students was the subject of a recent report by PBS television.

A film crew from the PBS News Hour with Jim Lehrer visited the USCGC Healy, a U.S. Coast Guard icebreaker, in the Arctic Ocean in August. They spoke with Lee Cooper and Jackie Grebmeier, of UT’s ecology and evolutionary biology department, about their experiences working on the Shelf-Basin Interactions program.

The National Science Foundation, the Office of Naval Research and the U.S. Coast Guard sponsored the voyage.

The UT research group participating in the summer Arctic work included science coordinator Arianne Balsom, graduate students Rebecca Pirtle-Levy and Catherine Lalande and undergraduate student Alicia Clarke, as well as other scientists from the United States and other countries.

“We couldn’t have done it without the students,” Cooper said. “On the ship we showed them how to do the experiments, and then we got out of their way.”

The researchers spent most of the summer taking ice, water and seabed samples from the deepest and most northern reaches of the ocean during two 40-day cruises, which ended in late August.

Cooper said the trip wasn’t easy.

“I don’t think people appreciate how hard you have to work out there,” he said. “When you say ‘I went on a research cruise,’ it sounds fun, but we worked in shifts, 24 hours a day, seven days a week to get our measurements done.”

Cooper said Shelf-Basin Interactions is a multi-disciplinary research program that uses microbiology, nutrient chemistry, physical oceanography, optics and educational outreach to understand environmental change in the Arctic region.

The measuring-stick they use, Grebmeier said, is carbon.

“As worldwide temperatures rise and sea ice retreats, changes are happening in the amount and distribution of carbon in the environment,” she said.

“We’re looking at levels of carbon in sea ice, seawater and sediments on the ocean floor over time, and how that movement impacts biological communities in the Arctic.”

Some of the impacts already seen are heartbreaking, Grebmeier said.

“Baby walruses usually stay on ice floes while their mothers hunt for clams and other food,” she said. “But warmer temperatures mean less ice, which means the babies get separated from their mothers in the vastness of the ocean.”

The hardest part, Grebmeier said, was when some lost baby walruses saw the Healy nearby.

“They were getting tired and had no place to go. When they saw us, they moved closer, barking at us, but we didn’t have any capacity or ability to save them. It really tugged at your heart, but there was nothing we could do for them,” she said.

This phenomenon was noteworthy, Cooper said, “because these are animals that have a very high investment in their young. And because walruses only reproduce every three years, a population decrease could have a negative impact on polar bears and other predators who feed on them.”

Humans are among those other predators that could be impacted, Grebmeier said. Because local Alaskans regularly eat walrus and bowhead whale, the loss of ice could lead to loss of a food supply and other economic disruptions along the Alaskan coast.

Ultimately, Cooper said, the hope is that their research projects will educate people around the world, so they will see the dangers posed by environmental pollution and will act to reduce that danger.

“The Arctic ecosystem is already changing,” he said. “In the last 20 years the ice has disappeared at a faster rate than ever measured before. And economic growth in China and India means more carbon dioxide in the atmosphere, in addition to the large amount already produced in the United States.

“At some point, society will have to take strong measures in response to these global changes.”

More information about this year’s Arctic cruise and the Shelf-Basin Interaction project can be found at http://sbi.utk.edu.