Greenhouse gas concentrations surged to unprecedented levels in 2023, locking the planet into a trajectory of rising temperatures, according to the World Meteorological Organization (WMO). The WMO’s latest greenhouse gas bulletin, released Monday, highlights the accelerating accumulation of carbon dioxide in the atmosphere—now increasing faster than at any point in human history. In just two decades, CO2 concentrations have jumped by 11.4%.

This past year saw a notable increase in CO2 emissions, exceeding 2022 levels and marking the second-largest annual rise in the last decade. The WMO attributes the sharp rise to a combination of severe forest fires and a decline in carbon absorption by forests, compounded by sustained human-generated CO2 emissions. The report also shows that methane and nitrous oxide levels reached record highs, with CO2 now standing at 151% of pre-industrial levels, methane at 265%, and nitrous oxide at 125%.

Ahead of the COP29 climate summit scheduled for next month in Baku, Azerbaijan, WMO Secretary-General Celest Saulo warned that these findings should “set alarm bells ringing” for global policymakers. “We are clearly off track to meet the Paris Agreement’s goal of limiting global warming to well below 2°C, with an aim for 1.5°C above pre-industrial levels,” Saulo noted. “These are more than just statistics; each part per million and every fraction of a degree increase has real consequences on our lives and our planet.”

In a related report, the United Nations also issued an assessment of the current state of national climate policies, finding that commitments made by countries under their Nationally Determined Contributions (NDCs) are still insufficient to curb the worst impacts of climate change. The UN report shows that the collective efforts fall far short of the emissions cuts required to limit warming to the Paris Agreement’s 1.5°C target.

According to the Intergovernmental Panel on Climate Change (IPCC), a 43% reduction in emissions is needed by 2030 to meet this target. However, under current policies, global emissions are only projected to decline by 2.6% from 2019 levels by the end of the decade—a reduction of about 51.5 gigatonnes of CO2, which the UN states is “marginal progress.” The report underscores the need for significantly more ambitious climate actions ahead of the February 2024 deadline for updated NDCs.

Simon Stiell, Executive Secretary of the United Nations Framework Convention on Climate Change (UNFCCC), emphasized the urgency of the situation, stating that current national plans are “miles short” of what is necessary to avert catastrophic climate outcomes. “This report should be a turning point,” said Stiell, urging leaders to deliver substantial progress at COP29. He further highlighted the transformative potential of ambitious climate policies, suggesting they could bring economic and social benefits alongside environmental gains.

The findings come on the heels of a sobering assessment from the United Nations Environment Programme last week, which indicated that the possibility of limiting global warming to 1.5°C above pre-industrial levels is “virtually zero.” The mounting evidence of missed climate targets has intensified calls for action, as COP29 approaches with renewed global focus on addressing the climate crisis.