The world’s major economies, many of who helped fuel the Earth’s warming over the past century through massive greenhouse gas pollution, are still failing to do their part to adequately tackle the problem, a United Nations report found Tuesday.

The annual U.N. emissions gap report details how the Group of 20 - comprised of 19 individual nations and the European Union - collectively are not on track to meet the emissions-cutting pledges they made as part of the 2015 Paris agreement, or the updated plans some countries have submitted ahead of high-profile climate talks next month in Scotland.

Given that developed nations account for roughly three quarters of global greenhouse gas emissions, the failures to set bold targets or to fully meet existing goals are a significant reason the world remains on a path toward worsening climate catastrophes, the U.N. found.

“We’re just so far off track, it’s really discouraging,” Drew Shindell, a Duke University earth science professor and co-author of Tuesday’s report, said in an interview. He said that while some countries are moving with more urgency, those efforts will lead only “to minimal change this decade,” unless major emitters make significant changes soon.

Despite the substantial gap that remains between the world’s current annual emissions and how much they must shrink to live up to the aspirations set six years ago in Paris, the report does make clear that there is evidence of progress.

Some key nations such as the United States, Canada and the EU have outlined new, stronger climate plans, which if implemented would result in sharp cuts to emissions in those nations by the end of this decade. Other large emitters, such as China and India, have not yet formally submitted new plans, but have announced domestic targets such as peaking greenhouse gas emissions by 2030 or installing colossal amounts of renewable energy, respectively.

Still, Tuesday’s report finds that the profound transformation away from fossil fuels is not happening nearly as fast as scientists have said is essential.

“We’re not bending the curve as much as we should,” Inger Andersen, executive director of the U.N. Environment Program, said in an interview. “We need to get much more ambitious.”

The U.N. report estimates that new commitments from about 120 nations, as of the end of September, could result in a 7.5% cut to the world’s greenhouse gas emissions by 2030 if fully implemented.

But emissions would actually need to fall about seven times that fast to hit the most lofty goal of the Paris agreement - limiting Earth’s warming to 1.5 degrees Celsius (2.7 Fahrenheit) above preindustrial levels. To remain at no more than 2 degrees Celsius of warming, the report found, would require cutting greenhouse gas pollution about four times as fast as current plans outline.

In addition, Tuesday’s findings highlight the fact that dozens of countries have pledged to reach “net zero” emissions by 2050. But while such vows are encouraging and could certainly limit future warming, many of those long-term plans are “vague” and “incomplete,” the authors say, and don’t detail near-term actions that would actually put nations on a track to achieve such promises.

“Many of them delay action right now. That’s a concern,” Andersen said. “A delayed action is an action we cannot afford.”

She added that global emissions, which fell briefly during the coronavirus pandemic, are expected to rise once again as economies rebound. But that economic recovery has largely not been a green one so far, according to Tuesday’s report. It found that less than 20% of recovery investments through this spring were likely to help reduce greenhouse gas emissions, and the vast majority of that spending came in rich nations.

The report offers the latest in a series of warnings in recent months, both about the world’s lackluster pace in tackling climate change and the consequences that could result if humans don’t move faster to eliminate greenhouse gas pollution.

A separate analysis from the United Nations on Monday of the specific commitments that countries have made ahead of the Glasgow climate talks - known as Nationally Determined Contributions - also found that nations are promising to do more to reduce emissions than in the past, but that the changes are not happening fast enough.

Already, the globe has warmed roughly 1.1 degrees Celsius compared to preindustrial levels. But the U.N. said Monday that even with the updated pledges from many countries, the world is on a trajectory projected to warm 2.7 degrees Celsius (4.9 degrees Fahrenheit).

That is a less disastrous path than only several years ago, but one that scientists say would be paved with intense flooding and wildfires, crippling sea level rise and other climate-fueled calamities.

Patricia Espinosa, executive secretary of the U.N. Framework Convention on Climate Change, said Monday that countries must “redouble” their efforts to cut carbon emissions, and that “overshooting the temperature goals will lead to a destabilized world and endless suffering, especially among those who have contributed the least” to climate change.

This week’s findings, as well as others that have come previously, send an unmistakable message that the world is quickly running out of time to stave off irreversible climate impacts.

Scientists have said that humans can unleash less than 500 additional gigatons of carbon dioxide - the equivalent of about 10 years of current global emissions - to have an even chance of limiting warming to 1.5 degrees Celsius (2.7 Fahrenheit) above preindustrial levels. That means the world could pass that threshold early in the 2030s without drastic changes.

Meanwhile, each of the past four decades has been successively warmer than any that preceded it, dating to 1850. Carbon dioxide in the atmosphere has risen to levels not seen in 2 million years. And this past summer was one defined by deadly fires, floods and heat waves, each reminders that climate change is no longer a problem of the future.

Those scientific realities are colliding with political ones beginning this weekend, when members of the G-20 meet in Italy, followed directly by U.N. climate talks in Glasgow through the middle of November. In both places, leaders will face pressure to offer action rather than only rhetoric, and one focus will be tangible steps that could help slow Earth’s warming, sooner rather than later.

“It requires political will. It requires ambition,” U.N. Secretary General António Guterres said in a recent interview. “But it will not be easy.”

One collective push will come on methane, the second most prevalent greenhouse gas, which doesn’t linger in the atmosphere as long as carbon dioxide but is far more potent. Sharply slashing the world’s emissions of methane - whether from oil and gas operations, agriculture or landfills - is one of the surest ways to limit warming in the short term.

Dozens of countries have recently embraced a pledge to cut methane emissions nearly a third by 2030, and Shindell said that “new appetite” for addressing the issue could represent a bright spot in the otherwise difficult math of climate change.

What’s important, he said, is to no longer wait.

“The rate at which you have to cut to reach net zero gets sharper and sharper the longer you delay,” he said. “Putting it off even to now makes it so we will require really rapid rates of decarbonization.”