FIGURE 1.

Held–Suarez simulation setup. (a) Equilibrium temperature distribution (calculated from Equation (1)), (b) relaxation time (Equation (2)), (c) zonal mean climatology of temperature (shading) and zonal wind (green contours in units of m$·$s${}^{-1}$), and (d) monthly temperature (shading) and zonal wind (contours) variance. The horizontal dashed line in (b) represents the parameter ${\sigma }_{\mathrm{b}}=0.7$, which can be interpreted as the top of the boundary layer. The 30‐year period of the no‐topography run is used to compute the model climatology in (c) and (d) [Colour figure can be viewed at wileyonlinelibrary.com]