Effect of land use on urban heat environment

Effect of land use on heat island is studied numerically by an urban climate model which employs the κ-ε turbulence model and an eddy diffusivity model for wind, temperature and moisture fields together with a heat budget model for surface boundary layer and soil layer. Simulations were performed for a simplified terrain which consists of sea and land. Natural, urbanized and urbanized but green augmented land use conditions are discussed. In urbanized area, it is clarified that decrease of latent heat flux and increase of sensible heat flux at urban surface raise temperature in the daytime. Urban canopy intensifies sensible heat transfer leading to higher air temperature. Sea breeze is blocked by the increased roughness in urbanized zone, resulting in the reduced cooling effect of sea breeze. The vegetation planting to increase moisture availability improves the thermal environment