Record Carbon Dioxide Levels Will Impact U.S. for Centuries, Says UN Weather Agency
GENEVA – Greenhouse gas concentrations in the atmosphere reached record highs in 2025, a trend that will lock in climate impacts persisting for centuries, according to the World Meteorological Organization (WMO).
The WMO's latest Greenhouse Gas Bulletin reveals that average global carbon dioxide (CO2) concentrations hit 426.8 parts per million (ppm) in 2025. This figure is 153% of the pre-industrial baseline levels from 1750. Levels of methane and nitrous oxide, the second and third most significant long-lived greenhouse gases, also reached unprecedented peaks.
"Another year, another new record," stated WMO Deputy Secretary-General Ko Barrett. "Greenhouse gases are trapping an unprecedented amount of heat in the atmosphere, providing energy for more extreme weather and associated risks to our economies and societies." Barrett emphasized that the past 11 years have been the warmest on record, a trend expected to continue, and that CO2's long atmospheric lifetime means its impact will be felt for decades and centuries.
The bulletin highlights that while the annual increase in CO2 from 2024 to 2025 was 2.8 ppm, smaller than the surge in the previous year, it still represents a substantial addition of carbon to the atmosphere from fossil fuel burning. The growth rate of CO2 has tripled since the 1960s, accelerating significantly in recent years.
This surge in greenhouse gases is occurring despite climate change mitigation agreements, with fossil CO2 emissions continuing to rise globally. Approximately half of the CO2 emitted annually remains in the atmosphere, with the remainder absorbed by the Earth's land ecosystems and oceans. The U.S. National Oceanic and Atmospheric Administration's (NOAA) Annual Greenhouse Gas Index shows that from 1990 to 2025, the warming effect on the climate caused by greenhouse gases increased by 56%, with CO2 accounting for about 81% of this rise.
The WMO's findings come ahead of the COP31 UN climate summit in Antalya, Turkey, scheduled for November 9-20. Experts warn that current mitigation policies may lead to global warming of around 2.8°C by the end of the century if drastic actions are not taken. The U.N. Framework Convention on Climate Change (UNFCCC) notes that countries are developing national emissions inventories and implementing mitigation actions, but fossil CO2 emissions remain on an upward global trend.
The WMO's latest Greenhouse Gas Bulletin reveals that average global carbon dioxide (CO2) concentrations hit 426.8 parts per million (ppm) in 2025. This figure is 153% of the pre-industrial baseline levels from 1750. Levels of methane and nitrous oxide, the second and third most significant long-lived greenhouse gases, also reached unprecedented peaks.
"Another year, another new record," stated WMO Deputy Secretary-General Ko Barrett. "Greenhouse gases are trapping an unprecedented amount of heat in the atmosphere, providing energy for more extreme weather and associated risks to our economies and societies." Barrett emphasized that the past 11 years have been the warmest on record, a trend expected to continue, and that CO2's long atmospheric lifetime means its impact will be felt for decades and centuries.
The bulletin highlights that while the annual increase in CO2 from 2024 to 2025 was 2.8 ppm, smaller than the surge in the previous year, it still represents a substantial addition of carbon to the atmosphere from fossil fuel burning. The growth rate of CO2 has tripled since the 1960s, accelerating significantly in recent years.
This surge in greenhouse gases is occurring despite climate change mitigation agreements, with fossil CO2 emissions continuing to rise globally. Approximately half of the CO2 emitted annually remains in the atmosphere, with the remainder absorbed by the Earth's land ecosystems and oceans. The U.S. National Oceanic and Atmospheric Administration's (NOAA) Annual Greenhouse Gas Index shows that from 1990 to 2025, the warming effect on the climate caused by greenhouse gases increased by 56%, with CO2 accounting for about 81% of this rise.
The WMO's findings come ahead of the COP31 UN climate summit in Antalya, Turkey, scheduled for November 9-20. Experts warn that current mitigation policies may lead to global warming of around 2.8°C by the end of the century if drastic actions are not taken. The U.N. Framework Convention on Climate Change (UNFCCC) notes that countries are developing national emissions inventories and implementing mitigation actions, but fossil CO2 emissions remain on an upward global trend.
This article and image are AI generated. For informational purposes only.