Installing solar panels in the U.S. Photo by: Oregon Department of Transportation/Creative Commons 2.0
For the first time in human history, carbon dioxide concentrations averaged out at 400 parts per million (ppm) worldwide in March, according to NOAA. Carbon dioxide concentrations have likely not hit such levels in two million years—long before Homo sapiens evolved.
“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. “Half of that rise has occurred since 1980.”
While the 400 ppm concentration was first recorded in 2012 in the Arctic, this March represents the first time that level was the average concentration worldwide. CO2 concentrations fluctuate throughout the year and around the globe.
Climate change is leading to rising sea levels, melting Arctic sea ice, vanishing glaciers, droughts and desertification, and intensifying extreme weather around the world. Scientists warn that climate change could lead to mass extinction as well as massive economic and societal impacts. Carbon emissions are also leading to ocean acidification, putting innumerable marine species at risk