Carbon dioxide levels in the atmosphere hit a record high, though total greenhouse gases decline due to pandemic

Carbon dioxide in the atmosphere, as recorded at the
Mauna Loa Observatory in Hawaii. (Washington Post chart)

Greenhouse-gas emissions have dropped because of the coronavirus pandemic, but the amount of carbon dioxide in the air just hit a record high.

"According to readings from the Scripps Institution of Oceanography and the National Oceanic and Atmospheric Administration, the amount of CO2 in the air in May 2020 hit an average of slightly greater than 417 parts per million. This is the highest monthly average value ever recorded, and is up from 414.7 ppm in May of last year," Andrew Freedman and Chris Mooney report for The Washington Post. "Carbon dioxide levels are the highest they’ve been in human history, and likely the highest in 3 million years. The last time there was this much CO2 in the atmosphere, global average surface temperatures were significantly warmer than they are today, and sea levels were 50 to 80 feet higher."

This sustained, and accelerating, increase in greenhouse gases is hastening global warming, the Post reports, which has serious implications for agriculture and more.