Changing Planet

UN: Oceans are 30 percent more acidic than before fossil fuels

By Daniel Grossman in Copenhagen

Since I began taking interest in global warming, I’ve heard scientists say “beware of surprises.” In the esoteric field of climate research, a surprise is bad: a dangerous unanticipated change to Earth’s climate, weather patterns, ocean currents and other “Earth systems,” or life on the planet. We usually expect that if a cause produces an effect, a little more of the cause will produce a little more effect. Many scientists worry that sometimes a little more cause might instead be the straw that breaks the camel’s back.  A big unexpected effect.  A surprise.

On Monday, the Convention on Biological Diversity, an international scientific organization, and the United Nations Environment Programme jointly issued a report raising new concerns about a serious problem of the suprise kind that climate researchers weren’t even aware of until about 5 years ago. Ask just about anybody about the consequences of putting too much carbon dioxide into the atmosphere, and most likely they will say the gas causes Earth to grow warmer. That’s true. But the extra carbon dioxide causes another problem: it dissolves in the ocean’s waters, creating carbonic acid. The new report says this effect, called ocean acidification, has already made sea water 30 percent more acidic since before industrial burning of coal and oil began about 150 years ago. The problem is that over-acidic sea water prevents some species from forming and retaining their shells. And these animals cannot live without protective shells.

I asked Thomas Lovejoy, who wrote the preface to the new report, what its findings mean. Until recently Lovejoy was president of the Heinz Center on Biodiversity in Washington. Before that he was the chief biodiversity advisor to the World Bank. I first met him about 25 years ago when I worked briefly at the World Wildfe Fund, where he was on staff at its Washington, D.C. headquarters. He had recently created an ingenious experiment for figuring out how clear-cutting in the Amazon affects wildlife in the forest that remains. He convinced loggers to leave patches of various sizes untouched in regions they cut down. At his request, the timber companies essentially created huge biological laboratories consisting of squares of virgin forest in the middle of cleared wasteland. Researchers are still making important discoveries about how much untouched woodlands different species need to thrive.

Lovejoy told me that the new ocean acidification study adds new urgency to climate negotiations, by confirming that carbon dioxide does much more than just warm the planet. He explained that researchers now predict that unless people find ways to produce much less carbon dioxide–or, in addition, begin soaking up carbon dioxide by planting vast numbers of trees–the acidity of the oceans will more than double in the next 40 years. This rate is 100 times faster than any changes in ocean acidity in the last 20 million years, making it unlikely that marine life can somehow adapt to the changes. Lovejoy says that thousands of tiny but critically important species at the base of the marine food chain with strange names (like foraminifera, pteropods and coccolithophores) will suffer directly from the change. Predators of these critters–and their predators, up to the top of the marine food chain–will suffer indirectly. The scientist says it’s “like pulling the rug out from under the marine food chain.”


Daniel Grossman has been a print journalist and radio and web producer for 20 years. He has reported from all seven continents including from within 800 miles of both the south and north poles. He has produced radio stories and documentaries on science and the environment for National Public Radio’s show Weekend Edition; Public Radio International’s show on the environment Living on Earth and news magazine, The World and many other international broadcasters. Among others, he has written for the New York Times, The Boston Globe, Discover, Audubon and Scientific American.

Forty years in U.S., UK, and South African media gives David Braun global perspective and experience across multiple storytelling platforms. His coverage of science, nature, politics, and technology has been published/broadcast by the BBC, CNN, NPR, AP, UPI, National Geographic, TechWeb, De Telegraaf, Travel World, and Argus South African Newspapers. He has published two books and won several journalism awards. He has 120,000 followers on social media. David Braun edits the National Geographic Society blog, hosting a global discussion on issues resonating with the Society's mission and initiatives. He also directs the Society side of the Fulbright-National Geographic Digital Storytelling Fellowship, awarded to Americans seeking the opportunity to spend nine months abroad, engaging local communities and sharing stories from the field with a global audience. Follow David on Facebook  Twitter  LinkedIn
  • Kevin Doyle

    This may seem like a “miss the point” question, but can I assume that a statement about “sea water” being 30% more acidic involves some kind of averaging?
    I ask because I wonder if some marine environments on the planet are particularly more affected by this increase than others.
    And, I ask *that* because I’m wondering if some of the world’s coral reef ecosystems will be particularly damaged by such an increase in ocean acidification.
    Thanks for this post, and for bringing back something from Copenhagen that’s not just more political speculation. Not much about the science being reported in the press back here.

  • senua

    All the time we here stories like this which are full of doom and gloom.
    But what about solutions. A lot of money seems to be spent on prooving that humas are destroying this that and the other but what about research on saving the environment, on solutions to help save endangered species and ways that humans can live with the minimum of damamge to their surroundings. Individuals are of course trying their best to lesson their impact on the planet. But it seems that scientists are too busy predicting doom and gloom to try and find and advise people on solutions to the various problems we face. The more we have doom laden stories like this the less likely people are to try and save the environment. If they have some positive ideas they can work with we might have a chance. People are looking up to scientists to come up with ideas and solution. How about finding some.

  • Lucien Alexandre Marion

    SOMETHING TO THINK ABOUT… (Lucien Alexandre Marion)
    SEA WATER…Oceans water more than 30% more ACIDIC than before fossil fuels. (UN)
    It started about 150 years ago…Weren’t we in the Industrial Revolution then…until today and it is continuing …
    Planting trees in the world could help reduce acidity…

  • EP

    It is true that maintaining hope for the future is very difficult in the face of all of the science about global warming and acidification of the oceans. I am grateful to the scientists for pointing out the problems and trying to wake us up so to speak. I for one am looking for solutions to fix the problems and I must remain optimistic in order to maintain my sanity. I look at the average American, if that is at all possible, and I am troubled. How is it that we can offer solutions without pointing a blaming finger, for there isn’t one of us,reading this, that isn’t responsible for adding to the problems we face with our planet. It is time to start offering solutions and it is time for us to start realizing that we must start implementing these solutions for out children, our planet and our sanity. How can we build more coal fired power plants?

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