Surface exchanges of sensible and latent heat in a 10‐level model atmosphere

Abstract This paper describes a representation of the distribution of sensible and latent heat from the surface through the atmospheric boundary layer which has been formulated for use in a 10‐level primitive equation model atmosphere. The transfer process is represented in two parts : (i) the transfer of energy across the Earth's surface into the lowermost 100 mb layer of the model atmosphere; and (ii) the subsequent redistribution of this energy through two or more such layers by small‐scale convection. The fluxes of energy across the surface are calculated using empirical ‘bulk aerodynamic’ relationships. In land regions consideration of the energy balance at the surface is also necessary, and diurnal variations of radiation are taken into account. The redistribution of energy by small‐scale convection is represented by convective adjustments which ensure that a certain neutral lapse rate of temperature is never exceeded. Some results of the incorporation of these effects into the 10‐level model are described.