UN Admits World Will Blow Past 1.5C

The United Nations conceded Wednesday that the world will blow past the 1.5-degree Celsius warming limit set in the 2015 Paris climate accord, and that the goal now is to limit how far past it goes and claw back down later.

The finding comes in a first-of-its-kind report from the Nairobi-based UN Environment Programme, titled "Limiting Overshoot," which calls the overshoot "unavoidable" and says it is likely within the next few years.

"There are no good outcomes above 1.5C," the report says.

The Numbers

The world is now at 1.4 degrees Celsius (2.5 degrees Fahrenheit) above pre-industrial levels by some scientists' calculations, measured as a 20-year average rather than a single year.

The most optimistic scenario in the report has warming peaking at about 1.8 degrees Celsius (3.2 degrees Fahrenheit) around mid-century if countries pursue ambitious climate goals. Getting temperatures back down to 1.5 this century is only possible if warming stays below roughly 1.8, the authors said — which they said would require global emissions to be cut in half by 2035.

Existing national policies are projected to produce at least 2.3 degrees of warming, according to the report, though it says staying below 2 degrees is still possible if governments deliver on their net-zero pledges by mid-century.

At up to 3 degrees, the report says glaciers could lose more than a quarter of their mass by 2100, raising sea levels by up to 13 centimeters, and global food production could fall by as much as 14% by 2050 without effective adaptation.