Climate experts expected better from the climate pact

While world leaders and negotiators they are hailing the Glasgow climate pact as a good compromise keeping a key temperature limit alive, many scientists wonder which planet these leaders are looking at.

By doing calculations, they see quite a different and warmer Earth.

“In the big picture, I think yes, we have a good plan to keep the 1.5 degree goal within our means,” said the United Nations climate chief. Patricia Espinosa told The Associated Press, referring to the overall global goal of limiting warming to 1.5 degrees Celsius (2.7 degrees Fahrenheit) since pre-industrial times.

UK Prime Minister Boris Johnson The conference host, agreed, calling the deal a “clear roadmap limiting the rise in global temperatures to 1.5 degrees.”

But many scientists are much more skeptical. Forget 1.5 degrees, they say. Earth is still on a path that exceeds 2 degrees (3.6 Fahrenheit).

“The 1.5 ° C target was already on life support before Glasgow and now is the time to declare it dead,” Princeton University climate scientist Michael Oppenheim told The Associated Press in an email on Sunday.

Some of the 13 scientists the AP interviewed about the Glasgow pact said they see enough progress to keep the 1.5 degree Celsius limit alive, and with it, some hope. But hardly.

Optimists point to many agreements that left Glasgow, including a United States-China They try to work harder together to reduce emissions this decade, as well as separate multinational agreements that focus on methane emissions and coal-based power. After six years of failure, a market-based mechanism would boost the trading of credits that reduce airborne carbon.

the 1.5 degree mark it is the stricter of the two targets in the landmark 2015 Paris climate agreement. United Nations officials and scientists consider it key because a 2018 scientific report found dramatically worse effects in the world after 1.5 degrees.

The world has already warmed 1.1 degrees (2 degrees Fahrenheit) since pre-industrial times, so it’s actually just a few tenths of a degree more. The United Nations calculated that to limit warming to 1.5 degrees, countries must cut their emissions in half by 2030. Emissions are now increasing, not decreasing, by about 14% since 2010, Espinosa said.

German researcher Hans-Otto Portner said the Glasgow conference “did the job, but did not make enough progress.”

“Warming will well exceed 2 degrees Celsius. This development threatens nature, human life, livelihoods, habitats and also prosperity,” said Portner, co-chair of one of the scientific reports of the Intergovernmental Panel on Climate Change. on which the United Nations is based.

Instead of big changes in the bending of the temperature curve as the United Nations expected from Glasgow, they only got small adjustments, according to scientists running computer simulations.

“By leaving Glasgow, we have reduced perhaps 0.1 ° C of warming … for a better estimate of 2.3 ° C warming,” Breakthrough Institute climate scientist and director Zeke Hausfather said in an email. Hausfather has done climate models with his colleagues to Carbon Brief.

Jon Sterman, a professor at MIT, said his Interactive weather The team did some preliminary numbers after the Glasgow deal came out and it didn’t match the optimism of the leaders.

“There is no plausible way to limit warming to 1.5 or even 2 (degrees) if you don’t remove the coal … and as quickly as possible, along with the oil and gas,” he said.

On Saturday, India received a last minute change to the pact: instead of the “elimination” of subsidies on coal and fossil fuels, the subsidies will be “phased out”. Several of the scientists said that regardless of what the deal says, coal must end, not just decline, to lessen future warming.

“‘Reduce’ will do less to curb the damaging effects of climate change than ‘eliminate,'” former NASA chief scientist Waleed Abdalati, who heads environmental research at the University of Colorado, said in an email.

Before the pact ended, Climate action tracker, which also looks at the promises to see how much warming they would cause, said emission reduction promises would lead to 2.4 degrees warming.

The 1.5 figure “is balanced on a razor’s edge,” said tracking scientist Bill Hare of Australia.

A paragraph of the pact, which asks countries whose emission reduction targets are not in line with the 1.5 or 2 degree limits to return with new, stronger targets by the end of next year, gives hope, Hare said.

But U.S. climate envoy John Kerry said Saturday night that the paragraph probably doesn’t apply to the United States, the second-largest emitter of coal and the largest historically, because America’s goal is very strong.

Jonathan Overpeck, a climate scientist who is dean of the University of Michigan’s school of the environment, said the pact offered “diluted hope. … We have an incomplete plan for slower action. “

“I walked into the (conference) thinking that 1.5C was still alive, and it seems that world leaders just didn’t have the backbone for that,” Overpeck said in an email.

Some progress was made, said University of Illinois climate scientist Donald Wuebbles, one of the key authors of the US National Climate Assessment. “But the probability of reaching 1.5 degrees is greatly reduced, even to the point of being almost impossible. Even being able to get to 2 degrees is less likely. “

But some scientists were hopeful.

“For the first time, I can really see a potential way to limit warming to 1.5 ° C,” said Michael Mann, a climate scientist at Pennsylvania State University, in an email. “But it will require both (a) countries to deliver on their current promises and (b) to further increase their current commitments.”

Johan Rockström of the Potsdam Institute for Climate Impact and Research in Germany highlighted the “optimistic” scenario that he and a few others see if all countries that have promised net zero emissions by mid-century actually achieve the goal, something that most have not. accomplished. a concrete action began.

In that case, warming could be limited to 1.8 degrees or 1.9 degrees, Rockström said.

“That is significant progress, but far from enough,” he said.

The Associated Press Department of Health and Science receives support from the Howard Hughes Medical Institute’s Department of Science Education. AP is solely responsible for all content.