Effect of Climate Change
by Tom Paulson
Seattle scientists pushing for further studies
Two decades ago, when Dr. Richard Feely at the Seattle laboratories of the National Oceanic and Atmospheric Administration reported his concerns about atmospheric carbon dioxide significantly altering the chemistry of the oceans, his findings were largely ignored.
Wednesday, Feely might have felt vindicated as one of the authors of a major federal report compiled by a blue-ribbon panel of scientists that pretty much said the same thing.
The report, jointly prepared by NOAA, the National Science Foundation and the U.S. Geological Survey, is titled "Impacts of Ocean Acidification on Coral Reefs and Other Marine Calcifiers." Although it may sound obtuse and perhaps limited in scope, it appears to represent a significant turning point -- expert consensus that this is a serious problem.
"This is the first time the issue has received this level of attention in the U.S.," Feely said. He said their findings of CO2-driven acidification of the oceans also will be included for the first time in the next report of the Intergovernmental Panel on Climate Change (a United Nations' panel widely regarded as the leading scientific organization on global warming).
"We still don't have a very good grasp of what this means for ocean biology," said the lead author, Joan Kleypas of the National Center for Atmospheric Research in Boulder, Colo. But there's no longer much question, Kleypas emphasized, that increased atmospheric emissions of carbon dioxide -- one of the main greenhouse gases driving climate change -- is also causing the world's oceans to become more acidic.
The acidification of the oceans, she said, could be what is already killing so many coral reefs across the planet.
"Coral reefs are like the rain forests of the ocean," noted co-author Chris Langdon, a coral expert at the University of Miami. Acidification of seawater undermines the skeletal structures of coral, Langdon said, which in turn undermines this basic marine ecosystem and harms other species that have evolved to depend upon it.
Chris Sabine, Feely's colleague at NOAA's Pacific Marine Environmental Laboratory in Seattle, said that the oceans tend to absorb over time the increased emissions of CO2 we've been putting out for the past 200 years or so since the industrial revolution began.
So far, Sabine said, the oceans have absorbed about 118 million tons of CO2, or maybe a third of the fossil fuel emissions. But the absorption in seawater causes a chemical reaction, producing carbonic acid. This, in turn, reduces the amount of calcium carbonate in the ocean -- which turns out to be a chemical widely used by marine life.
"We're basically generating acid in the ocean," Sabine said.
As the report notes in its introduction, the acidification of the oceans will ultimately be a temporary state that naturally corrects itself over time. But as we keep pumping CO2 into the sky and the chemistry of the oceans have to keep adjusting to deal with the carbonic acid, life in the oceans could suffer serious decline.
"The changes occurring in the ocean today are truly extraordinary," Kleypas said. "This needs immediate attention."
Feely agrees, noting with only a hint of annoyance that when he first tried to get his colleagues to pay attention to this issue, Sabine, now 41, was still in high school in Charleston, S.C. Perhaps the biggest turning point came in 2004, when the two Seattle scientists published their analysis of about 10,000 measurements of oceanic carbon concentrations that were taken from 95 research cruises worldwide.
Earlier this year, the NOAA scientists reported similar direct findings of ocean acidity on the increase from water and atmospheric tests made during a research cruise that stretched from Alaska to Tahiti.
The northern Pacific Ocean and its salmon stocks are especially vulnerable to CO2-driven ocean acidification, Feely said, because this part of the planet has "older" water that is already naturally rich in the gas. Some of the massive currents that connect the oceans accumulate carbon dioxide as they move, ending up in the north Pacific.
As acid levels rise in the surface waters, Feeley said, many species of plankton and other creatures at the base of the marine food chain can't develop properly because of the acid-caused decline in calcium carbonate.
"Calcification decreases significantly," Feely said. "Many of these species are the primary food sources for juvenile salmon and other important species for mankind. We may be having a very significant impact on the food web."
The report emphasizes that much more research is needed to determine what exactly is happening and the precise biological effect of the CO2-driven acidification of the oceans. Much of the findings so far are based on laboratory tests and speculation, the authors note, urging that more field studies be conducted.
Feely and Sabine, for example, hope to deploy many more than the dozen or so ocean-based CO2-measuring devices they now use to study ocean acidity.
"We just deployed another one off Aberdeen," Sabine said. They would like to get funding to expand on their ocean-based, CO2-monitoring system by deploying another 50 or so of these $25,000 devices on weather buoys worldwide. They also hope to collect data directly on additional research cruises.
"The Europeans have already recognized how important an issue this is and are moving ahead with the research," Feely said.
Given this new report, he said it appears the U.S. scientific community also is getting on board.
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