May 6, 2015
by Sarah Lazare, Staff Writer
Marking yet another grim milestone for an ever-warming planet, the National Oceanic and Atmospheric Administration revealed on Wednesday that, for the first time in recorded history, global levels of carbon dioxide in the atmosphere averaged over 400 parts per million (ppm) for an entire month—in March 2015.
“This marks the fact that humans burning fossil fuels have caused global carbon dioxide concentrations to rise more than 120 parts per million since pre-industrial times,” said Pieter Tans, lead scientist of NOAA’s Global Greenhouse Gas Reference Network, in a press statement. “Half of that rise has occurred since 1980.” More…