November 2025 Atmospheric CO2 Content: 426.46 ppm; November 2024: 423.85 ppm; November 2023 420.46 ppm

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4. Fundamental science on this predates the American Civil War

Eunice Foote demonstrated the absorption of heat energy from sunlight by CO2 and water vapor in a paper published in 1856. John Tyndall proved in a paper published three years later that it was infrared radiation providing heat energy.

Expanded groundwork in climate science came in the 1890s from Swedish physicist Svante Arrhenius and Edward Teller (of all people!) presented to the American Petroleum Institute's annual meeting around 1960, laying out in clear, simple terms what would happen if we kept on burning coal, oil and methane.

None of this is new, and none of it is remotely controversial.