Cooling effect of an urban park by enhanced heat transport efficiency

The mitigation of the urban heat island effect is an important environmental issue for sustainable urban development. We quantified the relative contributions to surface cooling associated with land use changes from an urban center to an urban park using the temperature decomposition method, with one-year paired eddy covariance measurements in Sakai, Japan. The enhanced heat transport efficiency achieved through park creation decreased daytime surface temperatures by 3.9-4.9 K, which was the greatest contribution to daytime surface cooling throughout the season. The disappearance of anthropogenic heat flux due to park creation reduced nighttime surface temperatures by 0.1-0.6 K, which was the greatest contribution at night in summer months. Enhancing heat transport efficiency through urban greening is thus a good mitigation strategy for cooling urban surfaces.