|By Aaron Sims | 3 years ago|
A new statistical study from the University of Washington shows a 90 percent chance that Earth’s temperatures willth rise by between 3.6 and 8.8 degrees Fahrenheit (2.0 and 4.9 degrees Celsius) during this century. This well exceeds the target set by the 2016 Paris Agreement of 1.5 degrees Celsius.
Details of the study are published in the journal Nature Climate Change.
“Our analysis shows that the goal of 2 degrees is very much a best-case scenario,” said lead author Adrian Raftery, a UW professor of statistics and sociology, in a statement. “It is achievable, but only with major, sustained effort on all fronts over the next 80 years.”
The new study identified three factors affecting future carbon emissions and global warming: total world population, gross domestic product per person, and “carbon intensity,” or the amount of carbon emitted for every dollar of economic activity.
By using statistical projections for each of these factors based on 50 years of past data, the researchers found that Earth is likely to warm by a median value of 5.8 degrees Fahrenheit (3.2 degrees Celsius).
“Countries argued for the 1.5 C target because of the severe impacts on their livelihoods that would result from exceeding that threshold,” said co-author Dragon Freirson, a UW associate professor of atmosphere sciences. “Our results show that an abrupt change of course is needed to achieve these goals.”
Raftery said that world population growth would have a relatively small impact on carbon emissions because most of that increase will occur in Africa, which consumes little in the way of fossil fuels. The most important impact for future temperature increases is carbon intensity, which depends on the way nations act to reduce emissions.