Carbon dioxide levels have reached the highest level in the history of mankind
The Earth's atmosphere now contains more carbon dioxide (co₂) than at any time in the history of mankind. For the first time ever, the average monthly CO₂ level exceeded 430 parts per million (ppm), according to experts from the Scripps Institution of Oceanography in San Diego.
The average value for May 2025 reached 430.2 ppm, the highest since accurate measurements began 67 years ago.
The more co₂ there is in the atmosphere, the higher the rate of global warming, which can subsequently make the Earth's surface too hot for human life. At significantly higher concentrations, CO₂ can also cause a number of health problems. The alarming consequences include cognitive impairment, drowsiness, nausea and, in extreme cases, even death.
"Another year is another record. It's sad," said Ralph Keeling, director of the Scripps Institution's Co₂ research program. Like other greenhouse gases, CO₂ acts as a blanket, trapping heat and warming the lower atmosphere. This changes weather patterns and fuels extreme events such as heat waves, droughts, wildfires, heavy rains, and floods.
Rising co₂ levels also contribute to ocean acidification, making it difficult for marine organisms such as crustaceans and corals to form hard shells and skeletons.
According to scientists, the current carbon dioxide content in the atmosphere is equivalent to what was observed about 4.1 to 4.5 million years ago, during what scientists call the "Pliocene climatic optimum."
At that time, sea levels were about 24 meters higher than they are today, and the global average temperature was 3.9°C higher than pre-industrial levels. In fact, the climate was so warm that vast forests covered the Arctic, where harsh, lifeless tundra stretches today.