eTheses Repository - University of Birmingham

6.3.3 Effect of urban growth on the DTR
As explained in Section 6.3.2 the DTR is a key meteorological indicator associated with
urbanisation and climate change. Figure 6.8 shows the change in the DTR for the urbanised
domains as a function of the mean urban land cover change, for all three series of
simulations.
DTR (K)
10.5
10.4
10.3
10.2
10.1
10.0
9.9
9.8
9.7
9.6
0.00 0.05 0.10 0.15 0.20 0.25 0.30
Mean urban land cover fraction
COMBINED SERIES RADIUS SERIES DENSITY SERIES
Figure 6.8: Mean DTR (K) as a function of the mean urban land cover fraction for the COMBINED,
RADIUS and DENSITY series, for the second day of simulation.
These results show that as the mean urban land cover fraction increases the DTR averaged
across the whole domain is reduced. For the RADIUS series this reduction in magnitude is
linear until a city size corresponding to a radius of 30 km and above is reached, and then
the results show a small change. This suggests a threshold for the change might be reached
around these values of the mean urban land cover fraction. The DENSITY and
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