Abstract
In recent years, high-albedo materials and products have been utilized for urban building roofs and roads to lower their surface temperatures. These high-albedo materials and products include those with spectral selectivity. Accordingly, a scale 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 region especially in hours with low solar altitudes. The distribution of the spectral albedo relative to the albedo over the entire spectrum agreed well between the experimental and numerical investigations. The effects of the spectral selectivity of urban materials on the urban albedo are discussed using the results from the numerical simulation.
