Carbon dioxide is a greenhouse gas produced by natural processes and everyday human activities, especially the burning of fossil fuels. The numbers here are from measurement of the concentration of carbon dioxide in the atmosphere made daily atop Hawaii's Mount Mauna Loa. Records have been kept since 1958.
Carbon dioxide concentration in the atmosphere is measured in parts per million -- ppm.
Sept. 29, 2019 -- 408.22 ppm
Sept. 29, 2018 -- 405.35 ppm
Go to scripps.ucsd.edu for more detailed information.
Earlier this month the Intergovernmental Panel on Climate Change released a report on impact of climate change on the oceans. You can read it here:
Special Report on the Ocean and Cryosphere in a Changing Climate
