Earth's atmosphere hasn't had this much CO2 in millions of years

Earth’s atmosphere now has more carbon dioxide in it than it has in millions — and possibly tens of millions — of years, according to data released Thursday by the National Oceanic and Atmospheric Administration and scientists at the University of California San Diego.

Earth’s atmosphere now has more carbon dioxide in it than it has in millions — and possibly tens of millions — of years, according to data released Thursday by the National Oceanic and Atmospheric Administration and scientists at the University of California San Diego.

For the first time, global average concentrations of carbon dioxide, a greenhouse gas emitted as a byproduct of burning fossil fuels, exceeded 430 parts per million (ppm) in May. The new readings were a record high and represented an increase of more than 3 ppm over last year.

The measurements indicate that countries are not doing enough to limit greenhouse gas emissions and reverse the steady buildup of C02, which climate scientists point to as the main culprit for global warming.

“Another year, another record,” Ralph Keeling, a professor of climate sciences, marine chemistry and geochemistry at UC San Diego’s Scripps Institution of Oceanography, said in a statement. “It’s sad.”

Carbon dioxide, like other greenhouse gases, traps heat from the sun and can remain in the atmosphere for centuries. As such, high concentrations of greenhouse gases in the atmosphere contribute to higher global temperatures and other negative consequences of climate change, including rising sea levels, melting polar ice, and more frequent and severe extreme weather events.