Daily Average Mauna Loa CO2:
Week beginning on Nov. 10, 2019: 410.25 ppm
Weekly value from 1 year ago: 408.91 ppm
Weekly value from 10 years ago: 385.76 ppm
Last updated: Nov. 19, 2019 Source: National Oceanic and Atmospheric Administration; Mauna Loa Observatory has been monitoring C02 levels since 1958