Some of the most headline-grabbing initiatives to emerge from COP26 come with big questions about how — and if — they'll make the journey from promises to reality.
Driving the news: COP26 brought the arrival or expansion of coalitions of nations making voluntary pledges around phasing out coal, cutting methane emissions, electric car growth, ending deforestation, curbing overseas fossil fuel finance and plenty more.
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While many of the biggest fossil fuel producers and users are missing from the deals, these ad-hoc agreements are still significant — if implemented.
Yes, but: They're outside the official Paris agreement process, which requires formal, albeit nonbinding, country pledges and periodic United Nations analyses of their cumulative effect and shortcomings.
It remains to be seen exactly how some of these coalitions — which include nations but also companies and other actors in some cases — will be tracked and held to account.
Quick take: The amount of scaffolding around the efforts will likely vary.
The "Global Methane Pledge" — which the U.S. and EU launched in September and mushroomed to over 100 countries at COP26 — already has some structure in place.
They're working with the multilateral Climate & Clean Air Coalition, and the pledge website says there will be "annual ministerial level meetings to review progress" too.
What we're watching: How many countries will, as officials and advocates hope, stitch the various vows into those formal submissions under the Paris agreement called "nationally determined contributions (NDCs)."
Evidence of whether that's happening could surface soon. The draft COP26 summit agreement pleads with countries to strengthen their NDCs by the end of 2022, speeding up the prior schedule.
The big picture: The rise of these deals shows that "it is difficult to get consensus on 190+ parties, but some countries are ready to take action now," Tufts University climate diplomacy expert Kelly Sims Gallagher said via email.
"Taken together, the ad-hoc pledges have the potential to have a significant impact on emissions, perhaps on par with the updates to the NDCs," adds Gallagher, an Obama-era State Department climate official.
But she also was quick to note the current absence of accountability and verification systems.
What they're saying: “COP26 in Glasgow has seen a plethora of commitments made by states and non-state actors, some credible, others less so," said Iskander Erzini Vernoit of the climate think tank E3G.
“For accountability, state commitments must be folded into countries’ nationally determined contributions and into actual legislation and policy," he said in an email exchange
Vernoit also says countries' and private sector commitments — and their credibility — must be weighed at what's known as the UN's "global stocktake" of how things are faring under Paris in 2023.
Of note: The UN's climate office, asked about the coalitions, said in a statement that the various announcements are "welcomed and will have a hugely positive impact if fully implemented."
It said Patricia Espinosa, the UN's top climate official, notes the commitments should be "backed up by implementation plans."
It's "up to Parties to identify whether to include any of the announced aspects in their NDCs," the UN said.
Why it matters: The coalitions could drive emissions cuts that add to existing vows, especially if more countries and others sign on.
The group Climate Action Tracker came out with an early attempt to size up four of the big ones — on methane, deforestation, clean transport and curbing coal — based on signatories as of Wednesday.
The group analyzes the large "emissions gap" between countries' NDCs and emissions cuts that would be consistent with the longshot Paris target of holding temperature rise to 1.5°C above preindustrial levels.
That "gap" closes by 24%-25% when you stack those four agreements on top of the updated NDCs, compared to 15%-17% based on the NDCs alone.
"Sectoral initiatives help implement action, but with current signatories only narrow the emissions gap to a limited extent," they find.
What's next: The UN already has initiatives to work with and encourage private sector commitments more broadly.
But Secretary-General António Guterres has signaled that he thinks more robust efforts are needed to track pledges from nations and companies.
"We need commitments to turn concrete. We need actions to be verified," he said in a speech earlier this week.
On a related point, he's also planning to convene a new group to create standards to measure and analyze the maze of "net-zero" emissions commitments by companies and other "non-state" actors.
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