The World Meteorological Organization (WMO) has reported a record surge in carbon dioxide levels in 2024, driven by continued human emissions, increased wildfire activity, and weakened absorption by land and ocean “sinks.” This combination of factors threatens to create a vicious cycle that could accelerate global warming.
According to the WMO’s latest Greenhouse Gas Bulletin, CO₂ growth rates have tripled since the 1960s, rising from an annual average increase of 0.8 parts per million (ppm) to 2.4 ppm per year between 2011 and 2020. The increase between 2023 and 2024 reached a record 3.5 ppm, the largest annual jump since monitoring began in 1957. Average atmospheric CO₂ concentrations climbed to 423.9 ppm in 2024, up from 377.1 ppm when the bulletin was first published in 2004.
Approximately half of all CO₂ emissions remain in the atmosphere, while the rest is absorbed by land and oceans. However, this natural storage is weakening due to reduced ocean solubility and worsening drought conditions. The 2024 spike was likely intensified by wildfires and a reduced capacity of land and ocean sinks, coinciding with the warmest year on record and a strong El Niño weather pattern. WMO senior scientific officer Oksana Tarasova highlighted concerns that declining sink effectiveness could leave more CO₂ in the atmosphere, further accelerating global warming.
Other greenhouse gases also reached record levels in 2024. Methane rose to 1,942 parts per billion (ppb), 166 percent above pre-industrial levels, while nitrous oxide reached 338 ppb, marking a 25 percent increase. WMO Deputy Secretary-General Ko Barrett noted that the heat trapped by these gases is driving extreme weather and emphasized that reducing emissions is critical for climate stability, economic security, and community well-being.
The WMO issued the report ahead of the COP30 climate conference in Belém, Brazil, underscoring the importance of sustained global monitoring to inform climate action and policy decisions.
