Abstract
This paper describes the effect analysis on ultraviolet radiation environments in the summer in actual urban street for various tree planting types using a numerical simulation tool previously developed. As an index of UV environment, in order to evaluate UV radiation received by the human body in an urban street, we used UV scalar luminance after considering the weighting factor for the surface area of the human body. A holiday promenade as a typical type of actual urban greenery area was selected for the analysis. We planted several types of trees different tree crown shapes and planting position for the street to compare the effects of the greenery. Simulation results showed that diurnal variations of UV scalar luminance for the tree planting types are different from the direction of human and sky view factor. For UV environments in an urban street, we received high reflected UV radiation from building façades and paved surfaces, including areas with shadows depending on the area. Therefore, spreading tree crown shapes will not only reduce UV radiation, but combining multi-layered planting with both tall and low tree coverage is effective.
