Aerodynamic roughness parameters in cities: inclusion of vegetation

Kent, C. W., Grimmond, S. ORCID: https://orcid.org/0000-0002-3166-9415 and Gatey, D. (2017) Aerodynamic roughness parameters in cities: inclusion of vegetation. Journal of Wind Engineering and Industrial Aerodynamics, 169. pp. 168-176. ISSN 01676105 doi: 10.1016/j.jweia.2017.07.016

Abstract/Summary

A widely used morphometric method (Macdonald et al. 1998) to calculate the zero-plane displacement (zd) and aerodynamic roughness length (z0) for momentum is further developed to include vegetation. The adaptation also applies to the Kanda et al. (2013) morphometric method which considers roughness-element height variability. Roughness-element heights (mean, maximum and standard deviation) of both buildings and vegetation are combined with a porosity corrected plan area and drag formulation. The method captures the influence of vegetation (in addition to buildings), with the magnitude of the effect depending upon whether buildings or vegetation are dominant and the porosity of vegetation (e.g. leaf-on or leaf-off state). Application to five urban areas demonstrates that where vegetation is taller and has larger surface cover, its inclusion in the morphometric methods can be more important than the morphometric method used. Implications for modelling the logarithmic wind profile (to 100 m) are demonstrated. Where vegetation is taller and occupies a greater amount of space, wind speeds may be slowed by up to a factor of three.

Item Type	Article
URI	https://reading-clone.eprints-hosting.org/id/eprint/71867
Item Type	Article
Refereed	Yes
Divisions	Science > School of Mathematical, Physical and Computational Sciences > Department of Meteorology
Publisher	Elsevier
Download/View statistics	View download statistics for this item