Climate change: Point of no return?

Eli Kintisch at Science magazine has put together a remarkable collage called After Paris: The rocky road ahead. Rocky indeed! The upper left graph shows steadily rising global emissions of carbon dioxide, with not even a glitch after the Kyoto meeting. The projections after the Paris meeting are not comforting either, unless we undertake a massive effort.

But now look at the lower-right graph. Does anyone believe that we – that is, the world – will really reduce investments in coal, oil, and gas production by over $100 billion per year between 2010 and 2029? Or that we will increase expenditures on energy efficiency by over $300 billion per year? Or that we will learn to sequester more than half our carbon dioxide emissions by 2100?

In a companion article, Climate crossroads, Kintisch tries to be optimistic and writes,

Optimists point to the growing use of solar, wind, and other renewable power sources and the success of some nations, such as Denmark (see p. 1020), in curbing emissions. But rising emissions from China, India, and other developing nations are swamping that progress. And the dismal track record of global climate talks inspires little confidence that nations can agree to make the huge changes required to stop treating the atmosphere like a carbon sewer.

Negotiators huddling in Paris next week are convinced these talks will be different. In Kyoto, nations attempted to create a legally binding agreement, which subsequently failed to deliver results in part because the United States would not ratify the treaty. This time, nations—164 of them, by the time Science went to press—have each prepared pledges, called Intended Nationally Determined Contributions (INDCs), which detail their promised emissions cuts and other actions through 2030.

Negotiators hope the bottom-up INDC approach will prevail where the top-down Kyoto strategy failed. Developing nations largely stuck to the sidelines in previous talks. This time almost everyone—including China and India (see p. 1024)—has pledged to limit emissions. And by arriving in Paris with pledges in hand, negotiators hope to avoid the last-minute deadlocks that have doomed past efforts.

I hope his optimism is not misplaced. I think we would rather not see Scranton, Pennsylvania, on the Atlantic coast in 2100 (upper right). [Sorry, it is Scranton, North Carolina, elevation, 0!]