World Barreling Toward 'Irrecoverable Overshoot of 1.5°C,' Report Warns During COP31

With world leaders, climate campaigners, scientists, and more gathered in Türkiye for the United Nations Climate Change Conference, an independent project that tracks government action warned Thursday that global warming is headed toward "an irrecoverable overshoot of 1.5°C" unless countries "rapidly reduce emissions to limit both the magnitude and duration of this overshoot."

A series of analyses released in the lead-up to the summit—including the United Nations Environment Program's "Limiting Overshoot" publication from September, the UNEP's "The Emissions Gap Report 2026: The Point of Return" from October, and the World Meteorological Organization's "State of the Climate: Update for COP31" from last week—have all sounded the alarm about at least temporarily surpassing 1.5°C, the Paris Agreement's global temperature rise limit for this century.

The new Climate Action Tracker (CAT) report, "Without Rapid Action, The World Is Heading to Irrecoverable Overshoot," lays out real-world action based on current policies; pledges and targets from the nationally determined contributions (NDCs) of countries that have signed on to the Paris Agreement; and the "optimistic scenario" based on all announced ambitions.

"Aggregated climate action has now essentially stalled for five consecutive years, with positive and negative actions canceling each other out," says the CAT briefing. "The warming outlook from current policies is leading to 2.7°C in 2100 (slightly up from 2.6°C) as it stood from 2021-2024."

"Our 2030 and 2035 targets scenario that assumes governments meet all their targets remains unchanged at 2.6°C in 2100," the report details. "The round of 2035 NDCs has closed: And it's clear governments have failed to meaningfully improve the outlook for end-of-century warming."

CAT's scenario that includes 2030 and 2035 NDCs as well as long-term targets projects "warming of 2.1°C in 2100, down from 2.2°C last year," the report continues. "Ambitious near- and long-term targets matter, but without credible policies and immediate implementation, they risk becoming empty promises rather than drivers of real-world emission reductions."

"Our optimistic scenario, assuming full implementation of all announced and net-zero targets, remains at 1.9°C in 2100," it stresses. "Even under our most optimistic assessment, if governments were to implement every single national pledge they have made—including the net-zero targets—we will still permanently overshoot the 1.5°C limit and get close to 2°C."

As both greenhouse gas concentrations and the profits of fossil fuel giants have soared while communities around the world face deadly heatwaves, rapidly intensifying hurricanes, rising sea levels, and destructive wildfires—like those that ravaged COP31 host Türkiye in September—scientists have reiterated warnings about the need for sweeping action to cut emissions.

"Continued warming from greenhouse gases emitted from human activities threatens to feed further warming as permafrost, wetlands, and wildfires destabilize and respond by releasing carbon dioxide, methane, and nitrous oxide," Ben Poulter, warming-induced emissions program director at Spark Climate Solutions, said in September, when a study he co-authored was published.

"This study provides a critical look at the magnitude of the temperature response," Poulter added, "and a call to action to accelerate the accounting and monitoring of warming-induced emissions to support pathways that phase out fossil emissions to stabilize the planet’s climate."

Bill Hare, CEO of CAT partner organization Climate Analytics, emphasized Thursday that "the stark choice for governments is to either continue to support the fossil fuel industry, which would consign humanity to insurmountable economic damages, rising mortality from heat, and climate-driven diseases and disasters that they are unable to adapt to—or pivot to the solutions which are available and cheaper than ever."

"The imminence of breaching 1.5°C cannot be an excuse to open the door to defeatism—the focus has to be on accelerating action to limit the magnitude and duration of overshoot," he argued. "Every increment of warming above 1.5°C means even more significant consequences across climate, nature and human systems."

The report outlines "five key levers that could cut emissions at the speed and urgency needed to follow a Paris-aligned pathway, limiting the magnitude and duration of overshoot," which are:

• A transition away from fossil fuels;
• Deep methane cuts;
• Rapid renewables-driven economy-wide electrification;
• Carbon dioxide removal (CDR) as a complement to emissions cuts, not a substitute; and
• An end to deforestation.

"Governments collectively are simply not moving fast enough to adopt the policies that would enable us to escape from the emerging overshoot trap," said the lead author of CAT's report, Climate Analytics policy analyst Sarah Heck. "Worse, several are taking their foot off the accelerator and slowing their climate action—or in cases such as the USA, Canada, and New Zealand—rolling it back at a staggering level."

So far this week, Climate Action Network International has given its satirical "Fossil of the Day" award—long used to call out bad actors during climate summits—to New Zealand, for "dismantling its own climate commitments" under Prime Minister Christopher Luxon, as well as "absent leaders of wealthy countries," including Canada, Denmark, France, Germany, Ireland, Italy, Japan, the Netherlands, and Sweden.

While a key Democratic US senator is attending COP31, President Donald Trump is skipping the summit and has not sent a delegation, even though his country is the world's worst historical climate polluter. UNEP's report from last month highlights the dangers of the pro-fossil fuel agenda that the Republican leader has pursued since returning to power last year, including ditching the Paris Agreement, again.

Trump's ongoing illegal war on Iran has not only led to the deaths of thousands of people but also padded the pockets of those invested in the fossil fuel industry—including himself—while people around the world pay the price at the pump, due to Iran's restrictions on ship traffic through the Strait of Hormuz.

"With the closure of the Strait of Hormuz exposing our vulnerability to geopolitical shocks," said Niklas Höhne of CAT partner organization NewClimate Institute, "the case for renewables and electrification has never been stronger—and it does appear that global emissions could be on the verge of a peak and a much faster decline than we had previously thought."