UN warns climate pledges fall short of targets to curb global warming ahead of November talks

National pledges to cut greenhouse gas emissions still fall far short of what is needed to limit catastrophic global warming, the United Nations said on Monday as countries prepare for the next round of climate change negotiations in November.

The "nationally determined contributions" (NDCs) already submitted by countries to the UN are enough to cut global emissions by 2.6% from 2019 to 2030, up from 2% last year, the United Nations Framework Convention on Climate Change (UNFCCC) said in its annual assessment.

But they are far from sufficient to achieve the 43% cut that scientists say is required to stay within reach of a Paris Agreement target to limit global temperature rises to 1.5 degrees Celsius (2.7 Fahrenheit), it warned.

As part of their Paris obligations, nations must deliver new and stronger NDCs before a deadline in February next year, and the report's findings should mark a "turning point", said Simon Stiell, UNFCCC secretary general.

"Current national climate plans fall miles short of what's needed to stop global heating from crippling every economy and wrecking billions of lives and livelihoods across every country," he said.

"The last generation of NDCs set the signal for unstoppable change," said Stiell. "New NDCs next year must outline a clear path to make it happen."

Persuading nations to set and implement more ambitious pledges could depend on the success of COP29 climate talks beginning in two weeks in the Azerbaijani capital of Baku.

Nearly 200 countries will thrash out the details of a new global emissions trading system as well as a hefty $100 billion annual financial package to help developing countries meet their climate goals.

"What we are seeing is that in some cases, (the NDC process) might be used as a negotiating mechanism - more money for more ambition," said Pablo Vieira, global director of the NDC Partnership, a non-government group that is helping around 60 countries draw up updated pledges.

"They also want to make sure that the new NDCs are investable, that they have the necessary elements that will attract not just public finance, but also private," he said.

Atmospheric CO2 at new record

In a separate report, the UN's weather monitoring body said on Monday that greenhouse gases have been accumulating in the atmosphere "faster than any time experienced during human existence" over the last two decades.

Carbon dioxide concentrations hit a new high of 420 parts per million (ppm) last year, up 2.3 ppm from a year earlier, and they have risen by 11.4% in just 20 years, the World Meteorological Organization (WMO) said in its annual greenhouse gas bulletin.

There are already signs that rising temperatures are driving dangerous "feedbacks" that will further increase atmospheric greenhouse gas concentrations, the report warned.

Last year's increase in CO2 concentrations, the second largest annual rise of the last decade, could have been driven by a surge in forest fires, with the carbon released from Canada's worst ever wildfire season exceeding the annual emissions of most major countries.

CO2 concentrations are now 51% higher than pre-industrial levels, while methane - another potent greenhouse gas - is 165% higher than in 1750, WMO said.

"This should set alarm bells ringing among decision makers," said WMO Secretary General Celeste Saulo.

"These are more than just statistics. Every part per million and every fraction of a degree temperature increase has a real impact on our lives and our planet."