Atmospheric carbon dioxide measured at NOAA’s Mauna Loa Atmospheric Baseline Observatory peaked for 2021 in May at a monthly average of 419 parts per million (ppm), the highest level since accurate measurements began 63 years ago, scientists from NOAA and Scripps Institution of Oceanography at the University of California San Diego announced today.
Scripps’ scientist Charles David Keeling initiated on-site measurements of carbon dioxide, or CO2, at NOAA’s weather station on Mauna Loa in 1958. NOAA began measurements in 1974, and the two research institutions have made complementary, independent observations ever since.
In May, NOAA's measurements at the mountaintop observatory averaged 419.13 ppm. Scientists at Scripps calculated a monthly average of 418.92 ppm. The average in May 2020 was 417 ppm. Pieter Tans, a senior scientist with NOAA’s Global Monitoring Laboratory, noted that CO2 is by far the most abundant human-caused greenhouse gas, and persists in the atmosphere and oceans for thousands of years after it is emitted.
Continue reading at NOAA Research
Image via NOAA Research