Axisymmetric, nearly inviscid circulations in non‐condensing radiative‐convective atmospheres

We study the steady‐state axisymmetric circulation of nearly inviscid, compressible atmospheres with no condensible component. Assuming simplified non‐grey radiative transfer and instantaneous adjustment to convective neutrality, we present an analytical theory for the depth, width and strength of the Hadley cell in terms of the planetary radius and rotation rate, insolation, optical depth and atmospheric composition. Under equatorially symmetric insolation, the Hadley cell width predicted by the present theory is generally very close to the Boussinesq, Newtonian cooling result of Held and Hou. We also introduce a new scaling theory for Hadley cell width under solstitial insolation conditions. The theory compares favourably with axisymmetric numerical results and also with full general‐circulation model simulations of Mars and Snowball Earth.