On the Parameterization of the Mean Wind Profile for Urban Canopy Models

Urban canopy models (UCMs) are widely used to parameterize surface-atmosphere interaction in weather and climate models. The physical processes described by UCMs include turbulent exchange and wind patterns within the urban canopy. This study compares several parameterizations of the vertical mean wind profile used in UCMs against simulations of the turbulent flow over an inhomogeneous urban-like surfaces with direct numerical simulation (DNS) model. The configurations of urban surface morphology are considered in a simplified form (columns, rows, and blocks)  with different height, frontal area index and aspect ratio. The possibility of applying the considered approaches to wind profile parameterizations in single-layer urban canopy models are discussed. Evaluation showed that parameterizations which utilize more accurate turbulent length scales’ description and explicitly involve buildings density metrics are shown to be applicable for a wider range of urban canopy geometries.