Even with fossil fuel emissions starting to level off, greenhouse gases are increasing
Despite the good intentions of the 134 countries that have ratified the Paris climate agreement to cut greenhouse gas emissions, the concentration of CO2 in the atmosphere is still increasing at a record pace. For the second year in a row, instruments at NOAA’s Mauna Loa Baseline Atmospheric Observatory showed CO2 increasing by 3 parts per million in 2016.
The two-year, 6-ppm surge between 2015 and 2017 is unprecedented in the observatory’s 59-year record and marked the fifth year in a row that CO2 increased by 2 ppm or more, according to Pieter Tans, lead scientist of NOAA’s Global Greenhouse Gas Reference Network.
Tans said, “The rate of CO2 growth over the last decade is 100 to 200 times faster than what the Earth experienced during the transition from the last Ice Age. This is a real shock to the atmosphere.”
Globally averaged CO2 levels passed 400 ppm in 2015 — a 43-percent increase over pre-industrial levels. In February 2017, the CO2 levels at Mauna Loa had already climbed to 406.42 ppm.
NOAA has measured CO2 on site at the Mauna Loa observatory since 1974. To ensure accuracy, air samples from the mountaintop research site in Hawaii are shipped to NOAA’s Earth System Research Laboratory in Boulder, Colorado, for verification. The Scripps Institution of Oceanography, which first began sampling CO2 at Mauna Loa in 1956, also takes independent measurements onsite.
Emissions from fossil-fuel consumption have remained at historically high levels since 2011 and are the primary reason atmospheric CO2 levels are increasing at a dramatic rate, Tans said. This high growth rate of CO2 is also being observed at some 40 other sites in NOAA’s Global Greenhouse Gas Reference Network.
Rising CO2 means more heat being trapped in the Earth’s climate system, which means more melting ice and sea level rise, along with many other consequences. Check out a list of Summit Voice stories about the impacts of rising CO2 here.