In May, NOAA's measurements at the Mauna Loa observatory averaged 419.13 parts per million. Scientists at Scripps calculated a monthly average of 418.92 ppm. It's the highest level since accurate measurements began 63 years ago.
New analyses of global air measurements show that five years after an unexpected spike in emissions of the banned ozone-depleting chemical chlorofluorocarbon CFC-11, they dropped sharply between 2018 and 2019.
Atmospheric carbon dioxide measured at Mauna Loa Observatory reached a seasonal peak of 417.1 parts per million for 2020 in May, the highest monthly reading ever recorded. Monthly CO2 values at Mauna Loa first breached the 400 ppm threshold in 2014, and are now at levels not experienced by the atmosphere in several million years.
Oceanic and Atmospheric Research (OAR) - or "NOAA Research" - provides the research foundation for understanding the complex systems that support our planet. Working in partnership with other organizational units of the NOAA, a bureau of the Department of Commerce, NOAA Research enables better forecasts, earlier warnings for natural disasters, and a greater understanding of the Earth. Our role is to provide unbiased science to better manage the environment, nationally, and globally.