Despite net-zero pledges at COP26, world likely on track to warm 2.5 degrees C, U.N. report says

GLASGOW, Scotland — After nine days of emissions pledges and deforestation commitments and bans on overseas fossil fuel projects, nations at the COP26 climate summit wanted to know how much their promises had shifted the world’s warming trajectory.

The answer: It depends on whether those promises can be believed.

A United Nations preliminary analysis released Tuesday found a massive gap between countries’ long-term plans to zero out carbon emissions and the official, short-term plans they have actually submitted.

Actually meeting the far-off net-zero pledges would give humanity an even chance of limiting warming to about 1.8 degrees Celsius (3.2 degrees Fahrenheit) above preindustrial levels, the researchers say. But what countries are planning to do between now and 2030 makes those pledges impossible, and would lead to warming of about 2.5 degrees Celsius (4.5 degrees Fahrenheit).

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The findings come during the highly technical second week of the Glasgow summit, when diplomats huddle in windowless meeting rooms, attempting to hammer out the rules for assessing and enforcing the world’s climate goals.

And the latest projections underscore a growing frustration with the U.N. meeting: The lofty rhetoric of world leaders has not been followed up with the kind of concrete action that could turn those visions into reality.

The “optimistic scenario” presented in the updated “Emissions Gap” report would bring the world within striking distance of the Paris agreement goal of keeping warming “well below” 2 degrees Celsius (3.6 degrees Fahrenheit). But it would leave out-of-reach the more ambitious target of 1.5 degrees Celsius (2.7 degrees Fahrenheit) — a target that scientists and vulnerable communities increasingly say the world cannot afford to miss.

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Researchers say it’s more realistic to look at short-term pledges, which require immediate action and for which political leaders can more easily be held accountable. Here, new plans from China, Australia and Brazil, among other major emitters, don’t do much to alter the world’s trajectory.

“We shouldn’t be blinded by long-term promises,” said Joeri Rogelj, director of the Grantham Institute for Climate Change and the Environment at Imperial College London and a lead author of the U.N.'s updated emissions report.

“If you want to achieve net-zero goals in the long term, your near-term pledges have to put you on track to deliver them,” he added. “Otherwise, there is low confidence they will ever be achieved.”

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But the “Emissions Gap” report also shows why this week’s technical negotiations are so important, Rogelj said.

“It is essential to know what’s going on and hold countries accountable,” he said. “Because a lot of ambition without those strong data — even though ambition is important — it’s just woolly words, without anything solid.”

Among the issues negotiators are now attempting to sort out are requirements for countries to report their estimated emissions. A Washington Post investigation published this week found that many countries are providing unreliable data to the U.N., leading to a giant gap between reported emissions and what actually goes into the atmosphere.