If you’ve followed any news on climate change in the last decade or so, you’ve likely seen the figure 1.5 degrees Celsius thrown around a lot.
“Every decision we make should be geared to say, ‘Does this advance the 1.5 degrees or is it going to be more destructive and take us in the wrong direction?’” U.S. Special Climate Envoy John Kerry said Sunday from the United Nations’ COP28 global climate summit in Dubai, calling the figure our “North Star.”
Referring to the Paris Agreement’s target of keeping Earth from warming no more than 1.5 degrees Celsius since the Industrial Revolution, the number has become a rallying cry for climate advocates and scientists, who say the goal is humanity’s best bet on avoiding the most catastrophic outcomes of climate change by the end of the century. Venturing even 0.5 degrees past that threshold could drastically increase the frequency and severity of extreme weather, biodiversity loss, famine and water scarcity, as well as make it more likely that tipping points accelerate warming further, climate scientists say.
But out of the public’s eye, many top climate diplomats and leading scientists have believed for years that the chance of achieving 1.5 degrees of warming is slim to nothing. The planet has already warmed about 1.3 degrees, and a growing number of researchers and thought leaders in the climate movement are now stating that belief bluntly as negotiations begin in earnest at the U.N. climate conference.
At a COP28 panel held Sunday, some of the world’s leading climate institutions unveiled their latest report, breaking down key scientific findings into digestible highlights for negotiators at the summit. Their main finding, they said, was that progress to reduce global greenhouse gas emissions has been “so limited,” that overshooting the 1.5 degrees target is “inevitable” and could be permanent without radically changing almost every aspect of modern society—an unlikely outcome as nations expand their plans to build fossil fuel infrastructure to extract more oil and gas than ever before.
“We’re talking, at best … up to 1.8 degrees Celsius before returning back to 1.5 by the end of this century,” said panelist Johan Rockstrom, director of the Potsdam Institute of Climate Impact Research. “To return back to 1.5 by the end of the century requires that we do everything right: phasing out fossil fuels, transforming the global food system, maintaining all the carbon sinks and stocks on land and in the ocean, and scaling carbon dioxide removal. Everything has to happen simultaneously.”
Nearly 37 billion metric tons of CO2 was released last year, according to the International Energy Agency. At that rate, nations can emit just six-years-worth of additional CO2—250 billion tons in total—before 1.5 degrees is completely out of the question, Rockstrom said. Even if that goal is met, he added, it leaves just a 50 percent chance that temperatures can be brought back down to the 1.5 degrees threshold by the end of the century.
The report reiterates a similar finding by the U.N. Environment Programme, which said in its Emissions Gap Report last year that there is “no credible pathway to 1.5°C in place,” and that “only an urgent system-wide transformation can avoid climate disaster.” A study published last month and led by James Hansen, the scientist who first warned Congress of the climate crisis in the late ‘80s, projects that the planet will likely warm 2 degrees—at least temporarily—sometime in the next few decades. And Bill Gates, the billionaire tech mogul and one of the world’s biggest investors in clean energy, said in an interview this weekend in Dubai that he believes it “isn’t that likely” the world will even meet the Paris Agreement’s less ambitious goal of permanently keeping temperature rise below 2 degrees Celsius.
Some studies estimate about 2.7 degrees of warming by 2100 under the climate pact’s current pledges.Still, aiming for 1.5 degrees—even though the goal is unrealistic—could still serve a purpose, some climate scientists and advocates say. It’s a growing debate within the climate community: Will a more honest discussion about the chance of achieving 1.5 degrees warming help spur the public to act or will it foster despair and dull the sense of urgency?
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Tripling Renewable Energy Must Include Nuclear, Nations Say: Nearly two dozen nations, including the United States, Britain, France, Canada and Japan, called for the tripling of world nuclear energy capacity at the U.N. climate talks on Saturday as part of the efforts to reach net-zero emissions by 2050, The Japan Times reports. But nuclear power remains controversial in the wake of major environmental disasters like Fukushima and Chernobyl. Some environmentalists also oppose nuclear for its large water consumption and high costs, saying funds would be better spent on solar and wind.
Self-Reported Emissions From Oil Companies Are Way Off, Gore Says: Former Vice President Al Gore blasted oil companies Sunday at the COP28 global climate talks, the Associated Press reports, saying the carbon emissions they’re reporting “are just not right—and we can prove they’re not right.” Gore’s data firm, which presented its latest analysis at the U.N. summit, tracks carbon pollution from every nation and city across the globe with 352 million pieces of information. “The No. 1 surprise was how far off the reporting from the oil and gas industry is,” Gore said.
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