Global warming: Science vs. politics

behind the curve(Originally published in the Portland Tribune May 15, 2015)

On a frigid late-February day in the nation’s capital, U.S. Senator James Inhofe, R-Oklahoma, brought a snowball to the Senate floor to lend credence to his claim that global warming is a hoax.

Inhofe’s strategy has been to discredit the work of climate scientists who have found that carbon dioxide emissions are forcing global temperatures in an upward direction. Reed College professor Joshua Howe argues these scientists are true American heroes, whose discovery of global warming was one of the greatest scientific achievements of the 20th century.

Howe recently authored a book that aims to be global warming’s origin story, called “Behind The Curve: Science and the Politics of Global Warming.” He recounts the successful scientific efforts to understand global warming, and the failures of political leaders in Washington and at the United Nations to pass laws and reach international agreements that would control it. It ends, sadly, with the public’s failure to take anything more than symbolic measures to curb carbon emissions.

As Howe makes clear, scientists aren’t very good politicians, and scientific facts by themselves aren’t enough to persuade most people to change their destructive behavior.

Howe recounts how in 1896 scientists discovered that an increase of carbon dioxide in the atmosphere can increase temperatures on the Earth’s surface, and in 1957 found that the combustion of fossil fuels was adding carbon dioxide to the atmosphere.

Howe traces the work of a young chemist named Charles David Keeling, who in 1958 started tracking the concentrations of carbon dioxide in the atmosphere at a mountaintop laboratory in Hawaii. When charted on a graph, his monthly data points form an upward sloping line, now known as the Keeling Curve. The book’s title refers to attempts to understand the curve.

Keeling’s first measurement at Mauna Loa showed that for every 1 million molecules of gas in the atmosphere, 315 were CO2. In 2013, the “Keeling number” topped 400 for the first time.

The significance of that discovery is the compilation of data showing that carbon dioxide concentrations have been increasing in synch with rising global temperatures.

In 1963, Keeling was the first to describe carbon dioxide emissions from industrial sources as a pollution threat.

Scientists now know that the airborne carbon dioxide level at the beginning of the industrial revolution around 1800 was about 280 parts per million.

Noted climatologist Michael Mann of Pennsylvania State University, writing in the March 18 issue of Scientific American, suggests that if the world keeps burning fossil fuels at the current rate, in 2046 it will cross a threshold leading to “environmental ruin.” The threshold would be crossed when we reach 450 parts per million of CO2. In just three decades, Mann predicts, the global climate will be a disastrous 2.5 degrees Centigrade warmer.

Howe’s book tells us how scientists like Keeling figured out that the planet had stumbled onto this road to ruin. His dispassionate book lacks the outrage that such an account might inspire, given the powerful forces advocating that nothing be done to rescue the planet and the horrible consequences. Readers looking for outrage might opt instead for Naomi Klein’s recent book “This Changes Everything.”

The time span between 1958 and 2046 is 88 years. Keeling gave us a fair warning. We’ve had plenty of time to fix the problem. What happens next is on us.

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