CO2 Levels to Reach 429.6 ppm in May 2025, a Record Not Seen in Over 2 Million Years
In May 2025, atmospheric carbon dioxide (CO2) concentrations are forecast to reach 429.6 parts per million (ppm), marking the highest levels of CO2 in the atmosphere in over two million years. This projected surge represents a significant challenge to global climate goals, with the 1.5°C cap on global warming becoming increasingly out of reach.
A Steep Increase in CO2 Levels
The global atmospheric CO2 concentration is expected to rise to 426.6 ppm in 2025, a jump of around 2.26 ppm from 2024. This annual rise remains far above what is needed to meet the Intergovernmental Panel on Climate Change (IPCC) targets for limiting global warming to 1.5°C—targets that require a deceleration and eventual reversal of current CO2 buildup. According to the IPCC, the rate of CO2 increase should be reduced to approximately 1.8 ppm annually to remain within the 1.5°C threshold.
However, recent data shows the opposite trend. In 2024, CO2 levels rose at an unprecedented rate, surpassing the predictions of the Met Office, UK. The increase of 3.58 ppm from 2023 to 2024 shattered the previous record, driven by a combination of record-high fossil fuel emissions, reduced carbon capture by ecosystems, and massive releases of CO2 from global wildfires.
The Climate Crisis Deepens
In 2024, the world faced the hottest year on record, with extreme weather events escalating in frequency and severity. According to the World Weather Attribution’s analysis, catastrophic weather events such as heatwaves, droughts, wildfires, and floods devastated communities worldwide, killing thousands and displacing millions. In India alone, over 3,200 lives were lost due to extreme weather.
As carbon dioxide continues to accumulate in the atmosphere, the heat-trapping effects of this greenhouse gas are intensifying. Rising CO2 levels contribute directly to more extreme global temperatures, which in turn fuel severe climate phenomena, including rising sea levels, stronger storms, and persistent droughts.
The World Meteorological Organization (WMO) projects that 2025 could be one of the hottest years on record, with a continued rise in global temperatures likely to worsen the frequency and intensity of climate-related disasters. Extreme weather events are now considered one of the most severe global risks for the near future.
The Road to Mitigation: Urgent Action Needed
Professor Richard Betts of the Met Office emphasized that global warming will persist unless there is a complete halt in the buildup of greenhouse gases. While natural events like La Niña may temporarily reduce CO2 accumulation, the long-term solution requires a drastic and immediate reduction in global carbon emissions.
“Significant and rapid cuts in emissions are essential to limit the degree of global warming,” said Professor Betts. “This demands urgent international action.”
To stand any chance of keeping global temperatures within the 1.5°C limit, nations must urgently ramp up efforts to decarbonize their economies, halt deforestation, and enhance carbon capture technologies. Without these changes, the world will continue on a dangerous path toward irreversible climate damage.