GLASGOW, Scotland – As world leaders and negotiators hail the Glasgow climate pact as a good compromise that keeps a key temperature cap alive, many scientists are wondering which planet these leaders are looking at.
Crunching the numbers they see a quite different and warmer Earth.
“In the bigger picture, I think yes, we have a good plan to keep the 1.5 degrees target within our means,” UN climate chief Patricia Espinosa told The Associated Press, referring to the target. general global to limit 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 road map limiting global temperature rise to 1.5 degrees.”
But many scientists are much more skeptical. Forget 1.5 degrees, they say. The Earth is still on a path to pass 2 degrees (3.6 Fahrenheit).
“The 1.5 ° C target was already on life support before Glasgow and now it’s time to declare it dead,” Princeton University climate scientist Michael Oppenheim told The Associated Press on Sunday.
Some of the 13 scientists the AP interviewed on the Glasgow Pact said they see enough progress to keep the 1.5 degrees Celsius limit alive – and with it, some hope. But barely.
Optimists point to many agreements that sprang from Glasgow, including an agreement between the US and China to work more together to reduce emissions this decade, as well as separate multinational agreements targeting methane emissions and coal-fired energy. After six years of bankruptcy, a market-based mechanism would trigger commercial credits that deplete carbon in the air.
The 1.5 degree level is the stricter of the two goals of the historic 2015 Paris climate agreement. UN officials and scientists consider it critical because a 2018 scientific report found dramatically worse effects on the world after 1.5 degrees.
The world has already warmed 1.1 degrees (2 degrees Fahrenheit) since pre-industrial times, so that’s really a few tenths of a degree more. The United Nations has calculated that to limit warming to 1.5 degrees, countries must halve their emissions by 2030. Emissions have been increasing, not decreasing, by about 14 percent since 2010, Espinosa said.
German researcher Hans-Otto Portner said the Glasgow conference “did some work, but didn’t make enough progress.”
“Warming will far exceed 2 degrees Celsius. This development threatens nature, human life, livelihoods, habitats and even prosperity,” said Portner, who co-chairs one of the Intergovernmental Panel’s scientific reports. on climate change on which the United Nations is based.
Instead of big changes in bending the temperature curve as the United Nations hoped from Glasgow, they got only minor adjustments, according to scientists running computer simulations.
“On leaving Glasgow we reduced the warming by perhaps 0.1 ° C … for a better estimate of 2.3 ° C of warming,” said in an email the scientist and director of the climate Breakthrough Institute, Zeke Hausfather. . Hausfather made climate models with colleagues from Carbon Lettera.
MIT professor Jon Sterman said his team at Climate Interactive came up with some preliminary numbers after the Glasgow deal came out and that it didn’t match the leaders’ optimism.
“There is no plausible way to limit warming to 1.5 or even 2 (degrees) if coal is not phased out … and as quickly as possible, along with oil and gas,” he said.
On Saturday, India got a last-minute change to the pact: instead of “phasing out” subsidies for coal and fossil fuels, subsidies must be “phasing out.” Several scientists have argued that regardless of what the deal says, coal must end, not just decrease, to reduce future warming.
“‘Reduce’ will do less to slow the damaging effects of climate change than ‘eliminate’,” former NASA chief scientist Waleed Abdalati, who manages environmental research at the University of Colorado, said in an email.
Before the pact was concluded, Climate Action Tracker, which also analyzes pledges to see how much warming they would lead to, said emissions reduction pledges would lead to 2.4 degrees of warming.
The figure of 1.5 “is balanced on the edge of a knife,” said follower scientist Bill Hare of Australia.
A paragraph in the pact – calling on countries whose emissions reduction targets are not in line with 1.5 or 2 degrees to come back with new, stronger targets by the end of next year – gives hope, Hare said. .
But US climate envoy John Kerry said Saturday night that the paragraph probably doesn’t apply to the United States, the second-largest coal producer and the largest historically, because the U.S. goal is so strong.
Jonathan Overpeck, a climate scientist who is dean of the University of Michigan environmental school, said the pact provided “watered-down hope. … We have an incomplete plan for slower action. “
“I went to the (conference) thinking 1.5C was still alive, and it seems world leaders didn’t have the backbone for it,” Overpeck said in an email.
Some progress has been made, said University of Illinois climate scientist Donald Wuebbles, one of the key authors of the US National Climate Assessment. “But the probability of getting to 1.5 degrees is very small, to the point of being almost impossible. Even being able to get to 2 degrees is less likely “.
But some scientists have been hoping.
“For the first time, I can really see a potential path to limiting warming to 1.5C,” Pennsylvania State University climate scientist Michael Mann said in an email. “But it will require both (a) that countries keep their current commitments and (b) that they further strengthen 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 meet the target – something that most party did not take concrete action on.
If so, the warming could be limited to 1.8 degrees or 1.9 degrees, Rockström said.
“This is significant progress, but far from sufficient,” he said.
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