Scale model experiment and numerical simulation on spectral albedo of urban surfaces

In recent years, high-albedo materials and products have been utilized for urban building roofs and roads to lower theirsurface temperatures. These high-albedo materials and products include those with spectral selectivity. Accordingly, ascale model experiment and a numerical simulation were conducted to investigate the spectral dependency and characteristics of the urban albedo. The experimental results suggest that the spectral albedo is high in the near-infrared regionespecially in hours with low solar altitudes. The distribution of the spectral albedo relative to the albedo over the entirespectrum agreed well between the experimental and numerical investigations. The effects of the spectral selectivity ofurban materials on the urban albedo are discussed using the results from the numerical simulation.