eTheses Repository - University of Birmingham

using different building parameters. The performance of BEP has been validated for the city of
Athens (Martilli 2003), for Basel with measurements from the BUBBLE campaign (Hamdi et al.
2005; Roulet et al. 2005) and for Marseilles with measurements from the ESCOMPTE campaign
(Hamdi et al. 2005). In general the validations find the largest differences between simulations
with and without BEP occur for downtown and suburban areas during night time, with rural sites
showing similar results. Following the implementation of the BEP scheme better agreement is
found with measurements for both daytime and night time conditions.
Since this work began, BEP has been chosen as the urban scheme to be implemented in a number
of mesoscale research and operational models, such as MC2 (Krayenhoff et al. 2005), TVM
(Hamdi et al. 2005), WRF (Martilli et al. 2007), DMI-HIRLAM (Baklanov et al. 2005) and the
Meteo Swiss operational Forecasting model aLMo (Clappier et al. 2005; Muller 2007). However,
it has the disadvantage of being more computationally expensive compared to a simpler scheme,
as well as the difficulty in obtaining all the required input information for an extensive domain.
Another disadvantage of the BEP scheme is that it does not include latent heat fluxes. This
means it does not take into account the contributions of urban parks and gardens to the surface
energy budget. This is overcome in this PhD study by using the relevant METRAS land surface
schemes to treat the urban vegetation.
A SWOT (Strengths, Weaknesses, Opportunities and Threats) analysis was carried out to
summarise the choice of the BEP and METRAS models (see Table 2.1 and Table 2.2).
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