422.8 parts per million
What was the global average concentration of carbon dioxide in the atmosphere in 2024?
At Mauna Loa, Hawaii, the monthly average reached 427.55 ppm in August 2026.
Source: NOAA Climate.gov (2024) climate.gov
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422.8 parts per million
At Mauna Loa, Hawaii, the monthly average reached 427.55 ppm in August 2026.
Source: NOAA Climate.gov (2024) climate.gov
280 ppm or less
Today's level of about 423 ppm is roughly 50% higher.
Source: NOAA Climate.gov (2025) climate.gov
about 8,887 grams
The carbon in the fuel combines with oxygen from the air as it burns, so the CO2 produced weighs more than the gasoline itself.
Source: U.S. Environmental Protection Agency epa.gov
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