In the early 2010s, climate scientists were painting a grim picture of the future: If humans didn’t curb carbon dioxide emissions, the world was headed toward 4 degrees Celsius (7.2 degrees Fahrenheit) of warming by the end of the century.
A decade later, the planet is on a different path. Scientists now estimate that current emissions trajectories make a 4-degree scenario highly implausible, even as total carbon emissions continue to rise. In fact, a new study estimates that if countries fulfill the climate pledges they made at the United Nations climate change conference known as COP26 last year, warming could be limited to just below 2 degrees C (3.6 degrees Fahrenheit) by 2100.
That’s a more optimistic outlook than those found in the assessments released in the months leading up to COP26. Based on the pledges that countries had made prior to the conference, those studies found that there was a less than 50 percent chance of keeping warming to below 2 degrees C, the goal set by the world’s countries in the 2016 Paris Agreement. Indeed, the commitments prior to COP26 put the world on track for a global temperature rise of 2.7 degrees.... Read more