Changing Planet

What Is the True Social Cost of Carbon?

A new study in the Journal of Environmental Studies and Sciences contends that the U.S. government significantly underestimated the social cost of carbon in 2010 in its effort to establish a unified cost of carbon for various agencies to use when formulating policy. The government arrived at a cost at $21 per ton of carbon, but the new study argues the “discount rate” was set too high, and that it the true social cost of carbon could be anywhere from $55 to $266 per ton.

Potential greenhouse gas policy, post-November, remains a murky picture. While candidate Mitt Romney has said he opposes a carbon tax, some of his economic advisers embrace the idea (subscription) as a means to tackle greenhouse gas emissions, especially in tight fiscal times. The Washington Post’s Ezra Klein frames the carbon pricing debate as a bargain between Democrats and Republicans, and a Slate piece offers that carbon taxes are good not only for the environment, but also for the treasury. Meanwhile, Daveed Gartenstein-Ross argues in The Atlantic that, given the national-security challenges the issue poses for the U.S., Romney and the Republican party are “ceding important ground by tolerating and encouraging denialism” of climate change. Ralph Nader says Obama and the Democrats are “running away from the issue” of climate change.

Climate Change in the Stone Age

Just like fossils, climate change leaves a trail in sediments, coral and buried pollen. A new study in the Proceedings of the National Academy of Sciences, which used models to simulate climate conditions over the last 120,000 years, indicates changes in climate coincided with some of early man’s migrations through Asia, north to Europe and all the way to Australia and North America. “The study fills in many of the links that have only been assumed or guessed at,” said Rick Potts of the Smithsonian National Museum of Natural History in Washington, D.C. It is the first time anyone has been able to explore climate’s power to facilitate human expansion, he added.

In the present day, humans’ expansion may cause urban areas to triple in size by 2030, placing more pressure on resources. Our everyday consumption  could be linked to record melting in the Arctic, making highly sought-after oil, gas and mineral resources more accessible. Local pollution created by the oil and gas industry, the United Nations Environment Programme (UNEP) says, may accelerate that thaw. “There is a grim irony here that as the ice melts … humanity is going for more of the natural resources fuelling this meltdown,” said Nick Nuttall, spokesman for UNEP. One need fueling this resource hunt: transportation. A new report says fuel consumption in new cars could be halved in less than two decades.

PBS Newshour has generated criticism for presenting “false balance” on the issue of climate change. Its Sept. 16 episode focused on the findings by “converted skeptic” Richard Muller that are consistent with the scientific consensus about climate change, but the show offered an equal-time rebuttal by climate change denier Anthony Watts—without disclosing his ties to the Heartland Institute, which has long promoted climate change denial. The New York Times’ Anthony Revkin called the interview with Watts “surreally softball.”

Country-Sized Emissions

Climate change may affect one ecosystem—covering 71 percent of the planet—most severely. As emissions continue to rise, ocean waters will rise with them, causing long-term degradation to about 70 percent of coral reefs by 2030. “Our findings show that under current assumptions regarding thermal sensitivity, coral reefs might no longer be prominent coastal ecosystems if global mean temperatures actually exceed 2 degrees Celsius above the pre-industrial level,” said lead study author Katia Frieler of the Potsdam Institute.

It turns out man-made emissions are not the only problem for our oceans. When disturbed, coastal habitats such as wetlands, mangroves and sea grasses, are also a huge factor in the production of greenhouse gases. Destruction of coastal wetlands, often as a result of urban development, aquaculture or farming, releases between 150 million and 1.2 billion metric tons of carbon per year with a central value of 450 million tons—10 times higher than previous reports. These coastal habitats could be protected and climate change combated, the study said, if a system were implemented that assigned credits to carbon stored in these habitats and provided economic incentive if they are left intact—much like what is being done to protect trees through reducing emissions from deforestation and forest degradation (REDD). It would work similar to what the American Carbon Registry has just developed for wetlands in the Gulf of Mexico.

The Climate Post offers a rundown of the week in climate and energy news. It is produced each Thursday by Duke University’s Nicholas Institute for Environmental Policy Solutions.

Tim Profeta is the founding director of the Nicholas Institute for Environmental Policy Solutions. The Nicholas Institute is part of Duke University and focuses on improving environmental policy making worldwide through objective, fact-based research in the areas of climate change, the economics of limiting carbon pollution, oceans governance and coastal management, emerging environmental markets and freshwater concerns at home and abroad.

In his role at the Nicholas Institute, Profeta has continued to use his experience on Capitol Hill to engage in climate change debates. His research has focused, specifically, on market-based approaches to environmental regulations—particularly energy and climate change policy. Other projects engage his expertise in environmental law and air pollution regulation under the Clean Air Act.

  • Lance Kevin Quinto

    I think the government should do its role in reducing the carbon footprint in the atmosphere. The government should tell their citizens what to do in order to live sustainably by eating organic foods, conserving energy resources, and by participating in the campaign in caring for the environment.

  • klem

    I think a more relevant question might be ‘What is the true social cost of bad breath?”

    Think about it. No seriously.

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