Thoughts

work in progress

We use the website Modtran Infrared Light in the Atmosphere for the calculations.

We assume a certain profile of atmospheric temperature is in equilibrium with the specified atmospheric constituents. The upward irradiance at a certain level (either 20 km or 70 km) is noted for this initial equilibrium profile. We seek to find the change in the temperature profile that could restore the upward irradiance after constituents are changed (such as doubling carbon dioxide). We could call that profile the new equilibrium profile.

For all experiments here, the temperature profile is 1976 U.S. Standard Atmosphere, with an optional specified uniform temperature offset (increase or decrease) as specified by the GUI. To the left is the initial assumed equilibrium profile, in blue, with 300 ppm of CO₂. The red is the predicted new equilibrium, after carbon dioxide is doubled and water vapor increase to preserve the specified relative humidity that was in the initial profile.

All are U.S. Standard Atmosphere and no clouds