Can We Fix Our “Broken” Ocean?

by Laurie Schreiber


 

“The timeframe for
coming back from this
is 10,000 years or more.”

– Ove Hoegh-Guldberg


WASHINGTON, D.C. – An international panel of experts shared the latest findings on ocean acidification, during two-day “Our Ocean” conference hosted by the U.S. State Department in June.

The conference brought together scientists, practitioners, advocates, lawmakers, and the international ocean and foreign policy communities to discuss ocean acidification, sustainable fisheries, and marine pollution.

“We’re taking life outside the conditions they evolved for,” said Ove Hoegh-Guldberg, inaugural director of the Global Change Institute and professor of marine science at The University of Queensland, in Brisbane, Australia. “The timeframe for coming back from this is 10,000 years or more. That’s our entire history, going from the Stone Age to the present. That’s a long time to pass on a broken ocean to our kids. We’re not talking about our grandchildren. We’re talking about 300 generations of humans.”

Hoegh-Guldberg discussed evidence of major disturbances to ocean organisms from global warming and acidification. For example, the tiny calcium carbonate shell of the sea butterfly is showing widespread occurrence of corrosion.

“They’re disappearing because can’t make a shell anymore,” he said. “Other fisheries depend on them. Thousands of other organisms depend on them. So we’re taking out a major component of the ocean and changing it forever.”

Hundreds of studies show a range of organisms – including corals, algae, plankton, shellfish and sea urchins – showing changes, he said.

“The chemical unraveling of these ecosystems has implications for humans,” Hoegh-Guldberg said. One of the ecosystems that graphically shows this these changes is coral reefs, occupying less than 1 percent of the ocean, yet containing one in every four species of marine organisms and collectively nourishing billions of people.

“Over the longer term, there’s serious concern that we’re starting to interfere with the very basic process of the ocean,” he said. “Experts agree there’s a need for rapid and deep cuts in emissions of global CO2, because nothing less will solve this diabolical problem of ocean acidifdation.”

Carol Turley, with the Plymouth Marine Laboratory in England and lead author on the 2007 Intergovernmental Panel on Climate Change’s 4th Assessment Report on Climate Change, said that, between the industrial revolution and the present, there’s been a 30 percent increase in ocean acidity.

“If we keep doing what we’re doing, by the end of the century, there will be between a 100 and 150 percent increase in acidity, across the whole global ocean,” Turley said.

Early vulnerability is seen in the polar oceans, which are naturally cold and therefore take up more carbon dioxide; as well as upwellings and estuaries.

Targeting between a 1- and 2-degree rise in global average temperature will reduce the amount of acidification, she said.

“We can do something about it,” Turley said.

Between July 2012-2013, Alexis Valauri-Orton traveled on a Thomas J. Watson Fellowship, investigating human narratives of ocean acidification in Norway, Hong Kong, Thailand, New Zealand, the Cook Islands, and Peru. She designed curricular tools for teaching about ocean acidification, and works with Global Ocean Health and Ocean Conservancy.

“Though acidification occurs in the sea, its potential impacts spread far onto land,” Valauri-Orton said. In Peru, for example, scallop farming is an important economic engine.

“Thousands of people will be affected,” by the decline of scallops due to shell corrosion, she said. “In each place I visited, I was shocked by how few people had heard of ocean acidification. Those with the most to lose have no idea of what they’re up against.”

Bill Dewey has worked for over 30 years as a shellfish farmer in Washington State. He is manager of public policy and communications for Taylor Shellfish Farms, the largest producer of farmed shellfish in the United States, and he owns his own clam farm, which produces 80 tons of clams per year.

Taylor has two shellfish hatcheries, in Washington and Hawaii, where seed is produced for clams and oysters. During their first few weeks of life, seed are most vulnerable to changing water chemistry.

“In 2006, our Washington hatchery started to see significant and repetitive oyster larvae mortality,” Dewey said. Reduced calcium carbonate in the water was “not good news for oyster farmers. These are building blocks for shells.”

In the oyster’s first 48 hours of life, 90 percent of its weight gain is shell. With less calcium carbonate, the oyster has to work harder to form shell, so it doesn’t have enough energy left to build the organ with which it feeds.

Between 2008 and 2009, he said, oyster growers were in a panic. However, Taylor was able to experiment at its Hawaii hatchery, where they didn’t see the same effects. Adding sodium carbonate to their water allowed them to recover a significant portion of their lost production.

“Ocean acidification is real,” Dewey said. “The world needs to grapple with carbon dioxide emission. And while we do, there are actions we can take to adapt and mitigate impacts that, in the short term, will help.”

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