Numerical Modeling for the Effect of High-rise Buildings on Meteorological Fields over the Coastal Area Using Urbanized MM5

Modeling the effects of high-rise buildings on thermo-dynamic conditions and meteorological fields over a coastal urban area was conducted using the modified meso-urban meteorological model (Urbanized MM5; uMM5) with the urban canopy parameterization (UCP) and the high-resolution inputs (urban morphology, land-use/landcover sub-grid distribution, and high-quality digital elevation model data sets). Sensitivity simulations was performed during a typical sea-breeze episode (4 similar to 8 August 2006). Comparison between simulations with real urban morphology and changed urban morphology (i.e. high-rise buildings to low residential houses) showed that high-rise buildings could play an important role in urban heat island and land-sea breeze circulation. The major changes in urban meteorologic conditions are followings: significant increase in daytime temperature nearly by 1.0 degrees C due to sensible heat flux emitted from high density residential houses, decrease in nighttime temperature nearly by 1.0 degrees C because of the reduction in the storage heat flux emitted from high- rise buildings, and large increase in wind speed (maximum 2 m s(-1)) during the daytime due to lessen drag-force or increased gradient temperature over coastal area.