Urban impacts on climate - The Global Climate System: Patterns, Processes, and Teleconnections - page 222

(a)

Figure 7.5 Variability of
air temperature at different
scales. (a, b) Hypothetical
representation of the spatial
features of the canopy layer
urban heat island in a mid-
latitude city with ''ideal''
(calm, clear) conditions.
Spatial pattern (a) along
cross section AB and (b) in
relation to plan outline of
the city (Oke 1982 ). (c, d)
Measurements in an urban
canyon (H/W 1.06).
(c) Temporal variation of
surface temperature on the
canyon floor together with
the air temperature at 0.5 m.
(d) Isotherm distributions
across a canyon for two
10-minute periods
(Nakamura and Oke 1988 :
permission from Royal
Meteorological Society).

B

A

DISTANCE

(b)

B

City core

+8

+4

Park

A

+2

Built-up area

(c)

50

N floor

40

Air

30

S floor

20

06 12

August 29

18 24 06 12 18 24

August 30

TIME (h)