Atmospheric carbon dioxide (CO2) has reached its highest level in at least 4.5 million years; it is now at 419 ppm, which is driving dangerous heating around the world.
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What is Happening?
- Modern measurements of CO2 began in 1958, and levels were at 316ppm. 300 years ago, before the beginning of the industrial age, that number was at 280 ppm.
- This shows that as a result of burning fossil fuels and cars, humanity has increased concentrations of the most important greenhouse gas by 50%.
- Atmospheric CO2 has risen every year since monitoring began.
- Two organisations have kept the historical record of atmospheric CO2 since 1958. The Scripps Institution of Oceanography pioneered the practice when climate scientist Charles David Keeling set up his equipment on Hawaii’s Mauna Loa volcano. The National Oceanic and Atmospheric Administration (NOAA) followed in 1974.
- Unfortunately, while COVID-19 related lockdowns and economic slowdowns reduced emissions significantly in 2020, it had little effect on the trajectory of CO2. The May average rose by 1.8 ppm over May 2020, slightly less than the annual growth rate for 2017 and 2011.
- CO2 levels aren’t determined solely by pollution, but also depend on variations in the rate that oceans and plants soak up CO2. The atmospheric concentration follows a seasonal cycle, peaking typically in May, when plants in the Northern Hemisphere- where most of them live- begin drawing CO₂ into tissue.
Ralph Keeling, a geochemist at Scripps and son of the scientist who launched measurements in 1958, says, “the ultimate control knob on atmospheric CO₂ is fossil-fuel emissions, but we still have a long way to go to halt the rise, as each year more CO₂ piles up in the atmosphere. We ultimately need cuts that are much larger and sustained longer than the COVID-related shutdowns of 2020.”
You might also like: Atmospheric Methane Levels See ‘Record’ Surge
- Data released in April 2021 by the NOAA found that methane levels in the atmosphere saw a record surge during 2020, marking the biggest increase since records began in 1983. Methane concentrations rose by 14.7 parts per billion in 2020.
