Chilean meteorologist collects air samples for NOAA's Global Greenhouse Gas Monitoring Network. (Credit: NOAA)
Worldwide carbon dioxide levels passed 400 parts per million in March 2015, according to a press release from the National Oceanic and Atmospheric Administration. NOAA researchers attribute human activity, specifically the burning of fossil fuels, to the spike in concentrations.
Scientists say that global carbon dioxide levels have climbed over 120 parts per million since before the Industrial Age, with 50 percent of the increase occurring since 1980. NOAA research also shows that carbon dioxide concentrations increased by nearly 3 parts per million from 2012 to 2014, a record jump.
Global CO2 levels are determined by air samples taken from 40 sites worldwide. The samples are collected in flasks from their locations and shipped to a NOAA laboratory in Colorado for analysis. Researchers predict that May carbon dioxide levels will remain at current levels due to natural cycles occurring in late spring.
Top image: Chilean meteorologist collects air samples for NOAA’s Global Greenhouse Gas Monitoring Network. (Credit: NOAA)