eTheses Repository - University of Birmingham

Chapter 5: Evaluation of the urbanised METRAS model
for the London region
The model results for an idealised domain have been analyzed in Chapter 4, and sensitivity
tests have been performed to investigate how the model responds to the urban area under a
variety of different conditions, such as changes to the building morphology and changes to
the synoptic conditions.
In this chapter the model was set up for a domain representing the London region, with its
current land cover. The aims of the chapter were to evaluate the performance of the model
by comparing the results with measurements from London weather stations and discuss the
difficulties encountered in model validation and to establish a baseline for current land use
for the comparisons in Chapters 6 and 7. Due to the high computational cost of running the
model, the runs are performed for single case studies which represent periods for which
significant effects of the urban area on the local climate are expected.
The evaluation of the METRAS+BEP model can be compared to the results of other
studies in which BEP has been used to represent the urban scheme within a mesoscale
model (Martilli 2003; Hamdi et al. 2005; Roulet et al. 2005). In general the implementation
of BEP was found to improve model results for all meteorological variables.
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