Slim hopes for Paris climate target
Earth will almost certainly warm by more than 2 degrees Celsius (3.6 degrees Fahrenheit) above preindustrial levels by the end of the century, the threshold set out in the 2015 Paris Agreement. That’s the sobering conclusion of a new study by scientists at the University of Washington, who analyzed population trends, economic growth, and the amount of carbon dioxide emitted for each dollar of economic activity. The researchers estimate there is only a 5 percent chance temperatures won’t rise above 2 degrees Celsius by 2100, and just a 1 percent chance the world will stick to the Paris accord’s more aspirational target of 1.5 degrees.
The most likely scenario based on current emission levels and targets, the team concludes, is that temperatures will increase between 2 and 4.9 degrees Celsius by 2100, with a median estimate of 3.2 degrees (5.8 degrees Fahrenheit). An increase that large would lead to a catastrophic rise in sea levels, severe heat waves, droughts, and other kinds of extreme weather, and millions being displaced. “The most optimistic projections are unlikely to happen,” lead author Adrian Raftery tells The Guardian (U.K.). “If we want to avoid [a rise of] 2 degrees, we have very little time left.” Raftery says the findings should serve as a call to action to global leaders, noting that a “breakthrough technology” or a rise in the use of renewable energy could dramatically alter the level of warming. ■