How to Use Computational Fluid Dynamics Models for Urban Canopy Parameterizations - Meteorological and Air Quality Models for Urban Areas - page 29

Fig. 4.1 Horizontal slabs where the spatial averages are computed
Fig. 4.2 Vertical profiles of (a) spatially averaged Reynolds stress and (b) dispersive stress
4.5 Conclusions
It is impossible to run an atmospheric model over an entire city and the surrounding
(in order to capture the mesoscale circulations) with spatial resolution of few meters,
needed to resolve explicitly the urban heterogeneity (buildings, roads, etc.). The best
resolution that can be achieved with today's computer is few hundreds of meters.
There is a need, then to develop and improve urban parameterizations for models
that do not resolve the buildings explicitely. In this contribution, we claim that CFD
micro scale models can play a very important role in the testing and development of
such parameterization, because they allow performing the needed spatial average,