Carbon dioxide levels highest in human history

The amount of planet-warming carbon dioxide in the atmosphere broke a record in May, continuing its relentless climb, scientists said Friday. It is now 50% higher than the preindustrial average, before humans began the widespread burning of oil, gas and coal in the late 19th century.

There is more carbon dioxide in the atmosphere now than at anytime in at least 4 million years, National Oceanic and Atmospheric Administration officials said. The concentration of the gas reached nearly 421 parts per million in May, the peak for the year, as power plants, vehicles, farms and other sources around the world continued to pump huge amounts of carbon dioxide into the atmosphere. Emissions totalled 36. 3 billion tons in 2021, the highest level in history.

As the amount of CO 2 increases, the planet keeps warming, with effects like increased flooding, more extreme heat, drought and worsening wildfires. Average global temperatures are now about 1. 1°C, higher than in preindustrial times. Growing CO 2 levels are more evidence that countries have made little progress toward the goal set in Paris in 2015 of limiting warming to 1. 5°C. That’s the threshold beyond which scientists say the likelihood of catastrophic effects of climate change increases significantly.


Although CO 2levels dipped somewhat around 2020 due to the pandemic, there was no effect on the long-term trend, Pieter Tans of NOAA’s Global Monitoring Laboratory said. The rate of increase in CO 2concentration “just kept on going”, he said. “And it keeps on going for about the same pace as it did for the past decade.