Carbon Dioxide Levels Hit Troubling Milestone
Source: Washington Post
Human influence on the Earth’s atmosphere touched what climate scientists called a dire milestone Friday as concentrations of heat-trapping carbon dioxide nudged up to a level unseen in about 3 million to 5 million years — long before modern humans.
A monitoring station in Hawaii recorded carbon dioxide concentrations of 400 parts per million Friday, dramatically up from the 316 parts per million recorded when the station made its first measurements in 1958. The monitor, high atop the Mauna Loa volcano, offers the longest-running record of atmospheric carbon dioxide measured directly from the air.