Climate Pledges Reach Threshold to Keep Warming Below 2C

(Bloomberg) -- The world can successfully keep global warming below 2C if every country meets every commitment made through June 2022 to slash greenhouse gas emissions, according to a new study.

That includes both medium- and long-term commitments. If countries were to meet only their 2030 goals, the report finds it wouldn’t be enough to keep warming at 1.5C or even “well below” 2C — limits baked into the Paris Agreement in 2015. But if national governments hit climate commitments for 2030, 2050 and 2070, four climate models concluded that limiting warming to 1.7C to 1.8C  is likely, per an analysis published Thursday in the journal .

"The main takeaway of this research is definitely positive," said Dirk-Jan van de Ven, the lead author on the report and a postdoctoral researcher at the Basque Center for Climate Change in Spain. "If all governments indeed follow the promises actually made, then we are actually keeping temperatures well below 2 degrees."

Using a collection of climate models, van de Ven and 15 colleagues worldwide set out to assess the impact of country-level climate commitments made leading up to and after the 2021 United Nations climate summit in Glasgow, COP26. Those updated pledges, they found, moved the needle on climate action in a meaningful way: Just a few years ago, the best-case scenario would have put the world on track to breach 2C. 

“The results clearly show that climate action and ambitions have notably improved since 2020,” the study’s authors wrote. 

The follow-through, though, is no small task. The researchers assessed the feasibility of the world collectively meeting medium- and long-term climate goals, and also looked at the challenges facing six major emitters: China, the European Union, India, Japan, Russia, and the US. Results varied widely by climate model. One model identified energy demand reduction as a feasibility challenge for the US, while another identified bioenergy and carbon storage as issues for Japan; yet another model called out carbon pricing as a challenge for the EU.

The study found that what is still out of reach, even if every single near- and long-term commitment on the books is fulfilled, is limiting warming to 1.5C. According to a recent forecast by the World Meteorological Organization, global temperatures are on track to temporarily pass 1.5C of warming in the next five years. The world has already warmed roughly 1.1C, intensifying heat waves playing out in Asia, droughts in Europe and floods in Pakistan. 

With each additional tenth of a degree of warming, those impacts are projected to get worse. A 2C world would usher in more climate disasters, push coral reefs to the brink of extinction, accelerate melting in the Arctic and result in greater sea level rise, threatening the very existence of multiple small island nations and coastal communities.

A UN report published in October similarly found that, if climate pledges were considered only through 2030, the world would still be on track to warm between 2.1C and 2.9C by the end of the century. Both studies show that short-term climate pledges remain far from putting the world on track to meet the Paris Agreement goals, adding weight to long-term pledges.

While the further ratcheting up of climate ambition “should not be lost,” the researchers behind the study wrote, the implementation of existing climate commitments “is currently the most relevant factor to avoid a climate disaster.”

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