Terrifying New Math and Old Politics

September 06, 2012
Bill McKibben, environmentalist and founder of, has written a starkly compelling new article, “Global Warming’s Terrifying New Math,” in Rolling Stone magazine that summarizes the bad news on climate change. He focuses on what he calls three scary numbers:  
  • 2 degrees Centigrade: the maximum temperature rise that scientists and even politicians in the Copenhagen Accord agree should be the target for planetary health
  • 565 gigatons: the maximum amount of carbon dioxide that can be added to the atmosphere by 2050 to “still have some reasonable hope of staying below [the] two degrees [target];”
  • and 2,795 Gigatons: “the amount of carbon…in the proven coal and oil and gas reserves of the fossil-fuel companies, and the countries (think Venezuela or Kuwait) that act like fossil-fuel companies.”
McKibben’s point is that the amount of carbon in the proven reserves is five times higher than the maximum emissions compatible with holding average temperature increase to 2 degrees centigrade, or 3.6 degrees Fahrenheit). And that’s without adding new sources of fossil fuel, like shale gas.  “We have five times as much oil and coal and gas on the books as climate scientists think is safe to burn,” McKibben writes. To minimize the risk of runaway climate change, “we'd have to keep 80 percent of those reserves locked away underground.” Citing the failures of the various climate and “earth” summits to reach agreement on how to contain the growth in greenhouse gas emissions, McKibben writes that “we're losing the fight, badly and quickly – losing it because, most of all, we remain in denial about the peril that human civilization is in.” In explaining why it’s so hard to find the political will to reverse the direction on carbon emissions, McKibben points to the huge vested interests of fossil fuel companies and the investors who fund them.  If limiting warming to 2 degrees means leaving 80 percent of proven reserves in the ground, that would mean a write-off of about $20 trillion in “stranded assets”  -- equivalent to the combined GDP of the world’s two largest economies, the US and China.  It would also mean a sizeable hit to the portfolios of pension funds, university endowments and other investors that hold fossil fuel company assets. But there’s another more insidious obstacle to mobilizing support for climate action. Record-hot summers and frequent storms in parts of the US notwithstanding, the impacts of climate change will be much less damaging in the rich countries that have contributed the bulk of carbon emissions and much more severe in poor countries. A new MIT study that analyzes data for the past 50 years finds that while climate change is devastating for poor countries, the impacts in wealthy countries are much smaller and in some cases may even be slightly positive.  The paper, “Temperature Shocks and Economic Growth: Evidence from the Last Half Century,” was published in July in the American Economic Journal: Macroeconomics.  The paper’s disturbing finding is that “every 1-degree-Celsius [temperature] increase in a poor country, over the course of a given year, reduces its economic growth by about 1.3 percentage points. However, this only applies to the world’s developing nations; wealthier countries do not appear to be affected by the variations in temperature.” More concerning, temperature increases in developing countries affect not just the current level of output but also may reduce future economic growth rates, which have a compound effect on economic outcomes in future years.  That means that the higher temperatures in a given year affect not only a country’s economic activity at the time, but its growth prospects far into the future. The paper’s estimates “show striking differences between rich and poor countries.” While it’s relatively straightforward to see how droughts and hot weather might hurt agriculture, the study indicates that hot spells have much wider economic effects; it finds that impacts are felt in a range of economic sectors, reducing industrial value-added, not just agriculture.  It also points to “large negative effects of increased temperature on poor countries’ exports, but not on rich countries’ exports.”  “What we’re suggesting is that it’s much broader than [agriculture],” one of the study’s authors, Ben Olken adds. “It affects investment, political stability and industrial output.” So while wealthy countries are paralyzed by the prospect of writing off $20 trillion of investment in fossil fuel assets, developing countries are already suffering the effects of climate change and the future prospects are even worse.


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