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Worldwide coral reefs are under threat

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Scuba diving in tropical waters near a coral reef sounds idyllic. The experience certainly wouldn’t be the same if the reef disappeared. However, if we keep pumping large amounts of CO2 into the atmosphere through the burning of fossil fuels, this is just what might happen. The ocean can only handle so much CO2 without suffering dramatic changes. The amount it has already absorbed since the Industrial Age 200 years ago has made it less alkaline and its pH has dropped by .1 pH units, increasing its acidity. This change may seem small, but even a very tiny change in pH can have potentially negative effects on many marine creatures—particularly those that make their shells from calcium carbonate like corals. If current trends continue, we may be saying good-bye to the reefs and their inhabitants.

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Feely, R. et al. (2006) Carbon Dioxide and Our Ocean Legacy, Pew Charitable Trusts, Retrieved March 9, 2008,  from The Ocean Acidification Network, http://www.ocean-acidification.net/ Off-site Link


Orr, J. C. et al (2005). Anthropogenic ocean acidification over the twenty-first century and its impact on calcifying organisms. Nature Online. Retrieved March 9, 2008, from
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