Estimate of the Heat Island and Building Cooling Load Changes due to the Restored Stream in Seoul, Korea

Abstract

Cities all over the world have been warming up in the summer over the years. Seoul, the capital of Korea, is also an example of a city which has been transformed into an urban heat island. Green areas produce social, economical, and environmental benefits in highly populated urban areas. This study is to investigate the micro—climate changes and urban—scale cooling load reduction by the recently restored Cheonggye stream, also known as Cheonggyecheon, in Seoul. Since the urban developments of the 1950's, the Cheonggye stream, located in central Seoul, has been covered with pavement and concrete overpass structures for over 50 years. A lot of surrounding buildings, traffic, and people caused the Cheonggye stream area to get hotter than other districts. For the urban environmental renovation, the 5.84 km—long stream was restored in September 2004. Since the restoration, the ecosystem in the center of Seoul has been reviving. This simulation study analyzes the micro—climate changes in the restored Cheonggye stream and its surroundings by using Envi—Met, a microclimate model designed to simulate the surface—plant—air interactions in an urban environment. We employed TRNSYS to estimate the urban—scale cooling load reduction by using the output data from the Envi—Met simulation. The results indicated that the cooling benefits of the restored stream areas are promising in the locations where the environment was restored.