After 15 days of tense negotiations, an agreement was reached Saturday by nearly 200 countries at the United Nations Climate Change Conference on how to address the growing crisis of global warming.
Though the deal includes several key pledges, including an agreement to reduce coal power and fossil fuel subsidies, many critics say the commitments do not provide enough support to developing nations that are disproportionately affected by global warming and are not aggressive enough to avert the worst impacts of climate change.
In his closing remarks at the climate summit in Glasgow, Scotland, U.N. Secretary-General António Guterres commended delegates from around the world on reaching a deal but acknowledged that there is more work to be done.
"Our fragile planet is hanging by a thread," he said in a video address. "We are still knocking on the door of climate catastrophe."
Guterres added that the agreement from this year's summit, known as the 26th "Conference of the Parties," or COP26, was a "compromise," and that "deep contradictions" remain. And while progress was made — including a landmark deal between more than 100 world leaders to end deforestation by 2030 and a surprise agreement between the U.S. and China to accelerate emissions reductions this decade — he said the nations most vulnerable to the effects of global warming need more support.
"These are welcome steps, but they are not enough," Guterres said.
The frantic final hours of the conference included a significant compromise on the language around coal power.
Early drafts of the COP26 deal called for countries to "phase out" coal, the dirtiest fossil fuel and biggest source of greenhouse gas emissions, and fossil fuel subsidies, but India led campaigns to water down the wording, replacing it instead with "phase down."
Greenpeace International Executive Director Jennifer Morgan called the changed language "weak and compromised," but added that, "its very existence is nevertheless a breakthrough."
The burning of fossil fuels, which unleashes carbon dioxide and other heat-trapping greenhouse gases, is the primary contributor to climate change, but the COP26 deal marks the first time the words "fossil fuels" have been written into a global climate pact.
Eighteen-year-old climate activist Greta Thunberg dismissed the outcome of the global summit but vowed to keep pushing for action.
"The #COP26 is over. Here’s a brief summary: Blah, blah, blah," she tweeted Saturday. "But the real work continues outside these halls. And we will never give up, ever."
The COP26 summit was seen as crucial to keeping alive the Paris Agreement’s goal of limiting warming to below 1.5 degrees Celsius, which scientists have said is necessary to avert the most devastating impacts of climate change.
The planet has already warmed 1.1 degrees Celsius, compared to preindustrial times, and studies have shown that staying below the 1.5 degrees Celsius threshold will require reducing global emissions by 45 percent by 2030.
Though one of the goals of this year's climate summit was for countries to set forth aggressive new targets for reducing emissions, a recent analysis by the U.N. Environment Programme warned that existing national pledges still put the world on track for more than 2 degrees Celsius of warming by the end of the century.
Diplomats at COP26 agreed that all countries need to do more to accelerate the reduction of greenhouse gas emissions, and the deal calls on governments to return next year to strengthen their 2030 targets.
Ani Dasgupta, president and CEO of World Resources Institute, a Washington-based research nonprofit organization, said the plan to revisit and intensify pledges more regularly will help keep the 1.5 degrees Celsius goal within reach.
"While we are not yet on track, the progress made over the last year and at the COP26 summit offers a strong foundation to build upon," he said in a statement. "The real test now is whether countries accelerate their efforts and translate their commitments into action."
The climate summit was supposed to end Friday but ran into overtime after disputes emerged over portions of the deal, including a framework for global carbon markets that would allow high-polluting nations or entities to trade or buy credits to offset emissions.
Disagreements over a provision known as "loss and damage," which centers around how to provide financial support to poor countries that contribute only a tiny fraction of global emissions but are suffering some of the worst effects of climate change, also threatened to derail negotiations.
Financing was one of the most contentious topics throughout the summit, and representatives from several developing nations and humanitarian organizations expressed dissatisfaction with the outcome of such talks.
Aminath Shauna, minister for environment, climate change and technology for the Maldives, said that progress was made at this year's summit, but added that, "this progress is not in line with the urgency and scale with the problem at hand."
"The difference between 1.5 and 2 degrees is a death sentence for us," Shauna said Saturday.
Still, COP26 president Alok Sharma said this year's proceedings mark an important stepping stone.
"We can now say with credibility that we have kept 1.5 degrees alive," Sharma said. "But its pulse is weak and it will only survive if we keep our promises and translate commitments into rapid action."
Next year's summit, COP27, is scheduled to convene in Sharm El-Sheikh, Egypt.