Mauna Loa Seas Adj Fossil Fuel Trend Graphic | Scripps CO2 Program

Mauna Loa Seas Adj Fossil Fuel Trend


Black Curve: Seasonally adjusted monthly average atmospheric carbon dioxide concentration versus time at Mauna Loa Observatory, Hawaii (20 °N, 156 °W) where CO2 concentration is in parts per million in the mole fraction (p.p.m.). The line through the dots is a spline fit to the data.

Red Curve: Fossil fuel trend of a fixed fraction (56%) of the cumulative industrial emissions of CO2 from fossil fuel combustion and cement production. This fraction was calculated from a least squares regression fit of the fossil fuel trend to the observation record. This fit is the equation a + b*f where a is the intercept of 296, and b is the slope of 56%.

Data from Scripps CO2 Program.

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