The annual growth rate of carbon dioxide in the atmosphere rose more in 2015 than scientists have ever seen in a single year, the National Oceanic and Atmospheric Administration announced Thursday.
It was the fourth year in a row that carbon dioxide concentrations grew by more than 2 parts per million, with an annual growth rate of 3.05 parts per million in 2015. The spike comes in the same year that Earth reached an ominous global warming milestone - scientists last year measured the highest atmospheric concentrations of carbon dioxide ever recorded.
Carbon dioxide emissions from people burning fossil fuels are the driving force behind climate change and have risen to greater than 400 ppm - more than 120 ppm above pre-industrial levels. Earth has warmed more than 1.6°F over that period.
As of February, the average atmospheric carbon dioxide concentration in the earth's atmosphere was about 402.6 ppm, according to NOAA data. The findings are based on measurements made at the Mauna Loa Observatory in Hawaii.