Bulk Radiative‐Convective Equilibrium Is Common Over Mid‐Latitude Land

Abstract Radiative‐convective equilibrium (RCE) is commonly used as an approximation of the time‐ and space‐averaged tropical atmosphere. We examine two reanalyses to assess the extent to which column‐integrated radiative cooling balances convective heating (“bulk RCE”) in the tropics and at higher latitudes. Our analysis shows that bulk RCE is a reasonable approximation of the tropics over ocean, but not land. Surprisingly, bulk RCE is often a reasonable approximation in mid‐latitudes, especially over land. These findings are explained by a simple argument. Over land, the ground heat flux is small, and bulk RCE arises when the top‐of‐atmosphere net radiative flux is small, which occurs in mid‐latitudes. Over ocean, the same mechanism applies but the ocean heat flux can be substantial and causes deviations relative to land. We conclude that bulk RCE is a surprisingly useful approximation of mid‐latitude land climate, which permits the development of simple theory for land climate, more broadly.