Planning scenarios and microclimatic effects: The case of high-density riverside residential districts in Seoul, South Korea

Abstract

Water bodies, such as rivers, ponds, and lakes, act as natural landscape resources to improve the urban microclimate. However, the cooling effects of water bodies may be lessened as a result of poorly planned buildings along the waterfront due to the “wall effect.” This research aimed to investigate the microclimate impacts of the following three strategies typically used in waterfront development: 1) building height restriction, 2) ventilation corridors, and 3) stepped building height variation. To compare the microclimate change after applying each strategy, we calculated the air temperature, wind speed, mean radiant temperature, and thermal comfort using the numerical simulation with microclimate simulation software, ENVI-met. The results showed that each strategy led to different microclimate patterns. The restriction on building height had a negative impact on the microclimate, increasing the physiological equivalent temperature by up to 1.34 °C. In contrast, the ventilation corridor provided a moderate cooling effect during the afternoon. Lastly, the stepped building height variation strategy did not have an effect on thermal comfort. The results suggest that the microclimate-related strategies for waterfront development did not always contribute to the improvement of thermal comfort; thus, additional heat-mitigation solutions are needed.