Current climate policies put the world on a course for 2.8 degrees C of warming this century, a gross breach of international climate targets, according to a new U.N. report.
Under the Paris Agreement, nations set a goal of limiting warming to 1.5 degrees C. But according to the latest U.N. “Emissions Gap Report,” the world is rapidly blowing past that threshold.
Average global temperatures over the past three years were more than 1.5 degrees C warmer than the preindustrial era, and there is evidence that warming is accelerating. While the planet has not officially surpassed the Paris goal, which will be judged by the average temperature over 20 years, overshoot is imminent. Beyond 1.5 degrees C, scientists see a growing risk that the Earth will cross planetary tipping points, from the dieback of the Amazon rainforest to the thawing of Arctic permafrost, that would further intensify warming.
In the best-case scenario, countries could reach peak warming of around 1.8 degrees C in the middle of this century, before drawing down vast volumes of carbon dioxide to bring warming back down to 1.5 degrees C, according to the new report.
“Overshoot is not surrender,” said U.N. Secretary-General António Guterres. “We can still keep it as small and as short as possible — and bring temperatures back below 1.5 degrees by the end of the century.”
But achieving this feat would demand a herculean effort, with countries slashing emissions by 18 percent by 2030 and 69 percent by 2040. Nations would also have to draw down 320 billion metric tons of carbon dioxide from the atmosphere. However, as the report notes, it is uncertain whether carbon removal technologies could even be scaled up to meet that goal.
One bright spot in the report: Renewable energy is growing more quickly than predicted when the Paris Agreement was adopted in 2015. Solar, in particular, has grown seven times faster than was anticipated.
“The emissions gap is now a leadership gap,” Guterres said. “And the world is running out of time and excuses to close it.”
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