Notes and Commentary on William Happer’s Presentation to Australia’s Institute of Public Affairs on the Effects of CO2 on temperature
September, 2023

The core narrative of the climate emergency crowd is that a higher concentration of CO2 in the atmosphere will cause a dangerous increase in global temperatures. As William Happer https://en.wikipedia.org/wiki/William_Happer explains, the premise is wrong. There therefore is no climate crisis and no need whatever to curtail the use of fossil fuels. What follows are highlights from Professor Happer’s presentation:

• A doubling of atmospheric CO2 has almost no effect on radiation from the Earth’s surface to space; a 100% increase in CO2 results in an only 1% decrease in radiation to space.
• The temperature increase needed to compensate for a doubling  of the concentration of CO2 is 0.71⁰ C (~1.3⁰F).
• Everyone agrees that the model based on these equations is correct – the physics are undisputed – and everyone also agrees that the model perfectly matches what is observed. Humans can’t feel the effect of such a trivial rise in temperature.
• To get the public alarmed about the effect of CO2, climate activists have to invoke the idea that a rise in CO2, which accounts for .04% of the total volume of the atmosphere (4 molecules out of every 10,000), invokes huge positive feedbacks from water vapor, clouds – whatever sounds plausible.
• There is, however, no evidence of such feedbacks.  Positive feedbacks almost never occur in nature. The reason is that they violate Le Chatlier’s principle: When a simple system in thermodynamic equilibrium is subjected to a change in concentration, temperature, or pressure, (1) the system changes to a new equilibrium and (2) this change partly counteracts the applied change. Simply put, the feedbacks are negative.
• An atmosphere with a concentration of 400 ppm (parts per million) is very much like a barn with red paint. A doubling of CO2 is like putting a second coat of red paint on the barn. The effect is negligible; the barn will not look noticeably redder after the application of the second coat.
• Nothing needs to be saved, but the climate people are unwilling to debate. Shame on them.