In a strategic retreat in the fight against climate change, the United Nations has recognized that the Earth has missed its chance to prevent some of the worst damage from global warming. So now the world must figure out how to get temperatures down from the danger zone and back to safety, officials say. The Earth will soon exceed the safe temperature threshold agreed upon by the world in the 2015 Paris climate agreement due to warming caused by the burning of coal, oil and gas, according to a grim report, the first of its kind, released Wednesday by the United Nations Environment Programme. Instead of giving up, scientists and UN officials recommend trying to limit excessive warming and then lowering the temperature to the agreed threshold. But it will still mean decades of greater climate-related disasters, sea level rise, extinctions, and melting ice and glaciers. “Humanity is accelerating beyond the limit to avoid a climate catastrophe,” said United Nations Secretary-General António Guterres. After a period of warming above the limit, the new strategy plans to return below the limit by ending the use of fossil fuels and developing some kind of way to absorb carbon dioxide from the air from industries. “It’s a reality check. We have to live with this warmer world,” said report co-author Richard Betts, a climate scientist at the University of Exeter. “But there is still a lot we can do to limit warming.” Overcoming long-standing warming thresholdAfter the Paris climate agreement, the United Nations ordered its climate science arm to study different warming thresholds. A target of 1.5 degrees Celsius (2.7 Fahrenheit) above mid-19th century temperatures became generally accepted after scientists found dramatic impacts affecting people and the planet at 2 degrees Celsius (3.8 degrees Fahrenheit), but not at 1.5 degrees. The world is now 1.4 C (2.5 F) above pre-industrial levels, some scientists have calculated. The measurement is based on a 20-year average, rather than temperatures from a single year. Even though experts say there is no way to limit warming to 1.5 degrees, U.N. officials long maintained that the 1.5-degree window remained open. Wednesday’s report finally admitted that the world will cross the 1.5″ threshold in the coming years. The report says the most optimistic scenario is for warming to peak at 1.8 C (3.2 F) by mid-century if countries pursue ambitious climate goals, but that current government policies should raise temperatures to 2.6 C (4.7 F) above pre-industrial levels by 2100. So instead of avoiding 1.5 degrees warming, the UN has now said it wants policymakers to “prepare and navigate.” for a future” in which the world crosses that limit and then corrects course and cools. The report predicts that global temperatures will exceed 1.5 “in the coming years,” follow a hump-shaped path of further warming, peak, and then gradually cool to below 1.5, ideally by the end of the century. The report and experts call it “overshoot.” But now we have to approach it differently than we did before,” said UNEP Executive Director Inger Andersen. The 1.5 limit is not “a magical climate cliff” where it is simply game over, said University of Victoria climate scientist Andrew Weaver, who was not involved in the study. “Every tenth of a degree we avoid means less damage.” Limiting how temperatures rise above the threshold is key. The most important thing is to first limit the new maximum temperature and “If we act now we can limit the excess,” the report says. of” 1.5 degrees in the long term. “This is one of the bleakest UN climate reports I have ever read. It carries an unmistakable tone of desperation, frustration and urgency, but not resignation,” Weaver said. Climate scientist Bill Hare, executive director of Climate Analytics, said that “while UNEP does a good job of describing the hole we’ve dug ourselves into, it doesn’t do a good job of showing us that there is a way out.” Adapting to a deadlier, hungrier and thirstier world Governments must increase their efforts to adapt to worsening warming, which hits the poor hardest, “because some “The impacts simply cannot be avoided,” Andersen said. The report calls this phase “coping and containment.” During this period of excess, more people will die or become ill due to worsening climate change and its extreme weather conditions, according to the report. Food production will fall, people will go hungry, water shortages will worsen, economies will be harmed and species like coral will become extinct, according to the report. Although the triggers for the recent deadly floods in Nepal, which occurred as part of the calving of a Himalayan glacier, are complex, Betts said that “unfortunately we expect to see more of this kind and that is exactly why we need to limit maximum warming.” The report warns of “tipping points” with irreversible and cascading effects, including the loss of the West Antarctic and Greenland ice sheets, the loss of the Amazon rainforest and the closure of the Atlantic Ocean circulation system that keeps much of Europe warm “Some places could turn so-so. unsafe or even uninhabitable,” the report says. The last phase of excess is to cool the planet by removing carbon dioxide from the air and storing it somewhere. The report says the traditional approach is to plant more trees, but it says planting trees could, at most, reduce global temperature by a tenth of a degree. So the authors said newer approaches to carbon removal will be needed. Other scientists called it unreliable and expensive. “We were unable to stop the runaway train of global emissions to avoid 1.5 C of warming,” said Stanford University climate scientist Rob Jackson, who was not part of the report. “Now, overshoot scenarios require us to stop the train quickly and turn back. Is it our best hope? Absolutely. Is it likely? Absolutely not.”___Associated Press climate and environmental coverage receives financial support from multiple private foundations. AP is solely responsible for all content. Find AP’s standards for working with philanthropic organizations, a list of supporters and funded areas of coverage at AP.org.
