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Boundary-Layer Meteorol (2013) 147:301327
DOI 10.1007/s10546-012-9786-6
ARTICLE
Dominique Groleau Patrice G. Mestayer
Received: 12 April 2012 / Accepted: 16 November 2012 / Published online: 20 December 2012 Springer Science+Business Media Dordrecht 2012
Abstract This heuristic study of the urban morphology inuence on urban albedo is based on some 3,500 simulations with the Solene model. The studied congurations include square blocks in regular and staggered rows, rectangular blocks with different street widths, cross-shaped blocks, innite street canyons and several actual districts in Marseilles, Toulouse and Nantes, France. The scanned variables are plan density, facade density, building height, layout orientation, latitude, date and time of the day. The sky-view factors of the ground and canopy surfaces are also considered. This study demonstrates the signicance of the facade density, in addition to the built plan density, as the explanatory geometrical factor to characterize the urban morphology, rather than building height. On the basis of these albedo calculations the puzzling results of Kondo et al. (Boundary-Layer Meteorol 100:225242, 2001) for the inuence of building height are explained, and the plan density inuence is quantitatively assessed. It is shown that the albedo relationship with plan and facade densities obtained with the regular square plot conguration may be considered as a reference for all other congu-rations, with the exception of the innite street canyon that shows systematic differences for the lower plan densities. The curves representing this empirical relationship may be used as a sort of abacus for all other geometries while an approximate simple mathematical model is proposed, as well as relationships between the albedo and sky-view factors.
Keywords Albedo Radiation trapping Shortwave radiation Sky-view factor
Urban albedo Urban climate Urban form
D. Groleaucole Nationale Suprieure dArchitecture de Nantes, CERMA UMR CNRS 1563, LUNAM Universit, 6 quai Franois Mitterrand, BP 16202, 44262 Nantes Cedex 2, Francee-mail: [email protected]
P. G. Mestayer (B)
CNRS, Institute for Research on Urban Sciences and TechniquesIRSTV FR CNRS 2488, LUNAM Universit, BP 92104, 44321 Nantes Cedex 03, Francee-mail: [email protected]
Urban Morphology Inuence on Urban Albedo: A Revisit with the SOLENE Model
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302 D. Groleau, P. G. Mestayer
1 Introduction
The urban albedo A is the primary characteristic determining the thermodynamics of an urban area since 1 A is the part of the solar energy that...