Pure steam runaway greenhouse, notebook

By assuming the atmosphere temperature profile follows a dry adiabat and the water vapour-condensate coexistence curve defined by the Clausius-Clapeyron relation, we see a characteristic relationship between the outgoing longwave radiation (OLR) and the surface temperature ($T_s$).

To follow this tutorial, run the Jupyter notebook located at docs/notebooks/01_canonical-runaway.ipynb

Initially OLR increases with $T_s$, but as the condensing layer (which is independent of $T_s$) overlaps with the photosphere, OLR and $T_s$ decouple. Eventually the atmosphere reaches a dry post-runaway state, and OLR increases rapidly with $T_s$.