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expected if the difference between the urban and rural albedo is removed by increasing the
albedo of the urban surface (Atkinson 2003).
A summary of albedo values for typical urban and rural surfaces is shown in Table 4.3. For
most surfaces a range is presented, as precise albedo values are not certain.
Table 4.3: Typical albedo values for rural and urban surfaces, taken from Oke (1987) and Taha (1997)
Surface type Albedo
Grass 0.16 - 0.28
Crops 0.15 - 0.24
Forests 0.10 - 0.18
Gravel 0.09
Tile roof 0.10 - 0.35
Asphalt 0.05 - 0.20
Concrete walls 0.10 - 0.35
Brick 0.20 - 0.40
Stone 0.20 - 0.35
Average urban areas (Oke 1987) 0.15
European and US cities (Taha 1997) 0.20
White paint 0.50 - 0.90
Simple modifications of the albedo in urban areas, for example by using high reflective
building materials, white surface coatings for roofs and walls, and lighter street surfaces,
could be part of a mitigation strategy in attempting to counter the effects of rising urban
temperatures, reduce cooling energy use and improve air quality (Oke 1987; Sailor 1995;
Bretz et al. 1998; LCCP 2002). Increasing the albedo will affect the surface energy balance
by increasing the percentage of incoming solar radiation which is reflected back to space.
The use of solar reflective, or high albedo, materials maintains low surface temperatures in
sunlight, and thus reduces the convective heat transfer from the surface to the ambient air,
and helps create cooler communities (Taha 1997; Bretz et al. 1998). For example Taha et
al. (1992) found a difference of 25 K between the temperature of a white surface (albedo of
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