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Just what motivates the world to tackle one global environmental threat but not another is somewhat of an enigma. Take, for instance, ozone depletion and greenhouse gas emissions.
We’re kicking butt on ozone depletion. Beginning in the 1980s, governments collectively began to act against the thinning of the stratospheric ozone that helps shield life on Earth from the sun’s damage-inducing ultraviolet radiation. Under a treaty called the Montreal protocol, countries around the world agreed to phase out the production of certain chlorine- and bromine-containing commercial chemicals, notably chlorofluorocarbons. All 193 United Nations countries participate in this accord. What’s more, scientific data show that action under the Montreal protocol has started to reverse ozone depletion.
The cooperation that led to the Montreal protocol provided momentum for countries to set their sights on another global environmental threat: human-induced climate change. In 1992, leaders from around the world, including President George H. W. Bush, signed a climate-change pact they hoped would lead to action similar to that on ozone.
But now, nearly two decades later, we’re slackers on climate change. Negotiations have come to a virtual standstill. Releases of greenhouse gases from the U.S., historically the world’s largest emitter, are untrammeled and are likely to stay that way until political winds shift. Industrialized countries that are reducing their emissions between 2008 and 2012 under the Kyoto protocol—a 1997 deal that the U.S. rejected—have made it clear that they aren’t going to sign up for further cuts if the U.S. doesn’t join in. Large developing countries with briskly rising emissions, including India and China, say they won’t curb their releases until after the U.S. does. Smaller, poorer countries that are projected to bear devastating impacts from climate change are caught in a situation they can do little about. Meanwhile, atmospheric concentrations of greenhouse gases continue to mount.
The markedly different policy outcomes on ozone and climate change stem from a variety of reasons.
From an overly simplistic view, the ozone problem involves a small number of players. A successful chemical industry unintentionally created—and through innovation is solving—the ozone depletion issue. Chemical makers aren’t working in a vacuum. They are collaborating with manufacturers of refrigeration equipment, those who service automotive air conditioners, and other manufacturers as well as governments.
In contrast, concerns about human-induced climate change are pegged to carbon dioxide emissions from the growing use of fossil fuels, driven by a growing demand for energy across sectors and societies. Addressing this problem will require much larger shifts than phasing out the use of a handful of chemicals. Needed actions include switching to other sources of energy, capturing CO2, reducing releases of greenhouse gases and sooty bits of black carbon, and adapting to unavoidable climate change.
At a recent conference in Washington, D.C., scientists who have been working on these two global issues for years offered perspectives on why the world has collaborated on the stratospheric ozone problem but not climate change.
First there are political factors. Denying that humans could fundamentally shift Earth’s climate has become a party line for Republicans, said Mario J. Molina, who shared the 1995 Nobel Prize in Chemistry for describing how synthetic chemicals deplete stratospheric ozone.
Plus, detractors are portraying climate science as a flimsy house of cards—if one study is shown to be wrong, the entire body of knowledge collapses into a worthless heap, said Molina, a University of California, San Diego, professor. A more accurate analogy, he continued, is a jigsaw puzzle. Many pieces are missing, and some already incorporated into the puzzle might be in the wrong place. Nonetheless, he said, enough parts are interlinked for us to see what the overall image is, namely that the climate is changing as a result of human influence.
There are also emotional reasons for the different levels of action. Susan Solomon, whose fieldwork in Antarctica provided real-world data linking synthetic chemicals to ozone depletion, zeroed in on the personal threat of skin cancer from greater exposure to UV in sunlight. Consternation over this risk drove support for action on ozone depletion, she said. In contrast, climate change is a more distant hazard and not so personal. Plus, many people feel their lifestyles would be threatened by policies to reduce greenhouse gas emissions, said Solomon, a researcher at the University of Colorado, Boulder.
One way to increase the emotional connection to the climate-change problem is to present it in more personal terms that could lead to support for action, Robert T. Watson told the conference. Watson, a former National Aeronautics & Space Administration researcher who worked on ozone depletion and chaired the Intergovernmental Panel on Climate Change for five years, is now a scientific adviser to the U.K. government.
Scientists and policymakers can describe projected climate change in terms of the things people deeply care about, Watson said. This includes jobs, food security, a stable economy, and energy security.
“That’s what resonates,” Watson said.
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