eTheses Repository - University of Birmingham

models, for example Martilli et al. (2002), Martilli (2003), Roulet et al. (2005) and Hamdi
(2005). The sensitivity tests have shown that urban characteristics such as the presence of
vegetation and the albedo, as well as size of the urban area, can have a significant effect on
urban temperatures. This has important implications for the design of cities and the
management of urban climate.
A more formal evaluation of the model was performed against meteorological data from
UK Met Office London weather stations for a set of case studies and found that the new
METRAS+BEP model performed better than the traditional representation of the urban
surface; however finding representative measurements for model evaluation was identified
as a problem for many cities. This PhD study focused on summertime anti-cyclonic
conditions since they are favourable to the development of UHIs. Under climate change
scenarios these weather conditions are likely to increase in frequency, which has the effect
of increasing the duration and frequency of strong UHI episodes (LCCP 2006).
Having evaluated the model performance, scenarios were run to simulate the effects of past
and future land cover changes on near surface temperature and wind fields. These scenarios
were constructed based on maps of past land use and assumptions on the future expansion
of London. Scenarios were run for 48 hours, allowing a detailed investigation of the effects
on near surface meteorological fields (Ichinose 2001; Klaic et al. 2002; Mölders et al.
2004). A full statistical assessment of the urban effects on long term climate was not
possible using these short term simulations and therefore this did not fall within the scope
of this PhD study. However the investigation of the physical processes involved in the land
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