Essential papers / books.

Robinson, T., Catling, D. Common 0.1 bar tropopause in thick atmospheres set by pressure-dependent infrared transparency. Nature Geosci 7, 12–15 (2014). https://doi.org/10.1038/ngeo2020

Shows planets with thick atmospheres have a tropopause at 0.1 bar; because at atmospheric pressures < 0.1 bar, transparency to thermal radiation allows short-wave heating (solar radiation) to dominate, creating a stratosphere. At higher pressures, atmospheres become opaque to thermal radiation, causing temperatures to increase with depth and convection to ensue. A common dependence of infrared opacity on pressure, arising from the shared physics of molecular absorption, sets the 0.1 bar tropopause.

The ratio (γ) of specific heats at constant pressure (c_p) and volume (c_v ), respectively, (γ = c_p/c_v ) sets the dry adiabatic lapse rate for the trophospheric adiabat, and is 1.4 for atmospheres dominated by diatomic gases.