The National Oceanic and Atmospheric Administration (NOAA) reported that May 9 measurements at its Mauna Loa Observatory in Hawaii showed the daily average concentration surpassing 400 parts-per-million for the first time since measurements there began in 1958.
There’s far more CO2 in the air now than there has been during the past 800,000 years, according to NOAA.
And carbon concentrations may not have been this high since the Pliocene era about three million to five million years ago, according to the Scripps Institution of Oceanography and other reports.
According to NOAA, pre-industrial revolution levels of CO2 were roughly 280 parts-per-million.
“During the last 800,000 years, CO2 fluctuated between about 180 ppm during ice ages and 280 ppm during interglacial warm periods. Today’s rate of increase is more than 100 times faster than the increase that occurred when the last ice age ended,” NOAA said.
Al Gore, in a blog post Friday, sought to use the milestone as a rallying point, noting the world’s food systems, cities, people, “and our very way of life developed within a stable range of climatic conditions on Earth.”