HR: 12:05h
AN: H52D-08    [Abstracts]
TI: Spatial and Temporal Impacts of Urbanization on Local Hydrological Processes - A Case Study in the Central Taiwan
AU: * Kuo, C
EM: ckuo@faculty.pccu.edu.tw
AF: Department of Geology, Chinese Culture University, 55 HwaKang Road,Yang-Ming-Shan, Taipei, 114, Taiwan
AU: Lin, C
EM: yao435@rcec.sinica.edu.tw
AF: Research Center for Environmental Changes, Academia Sinica, 128 section 2, Nangkang Road, Taipei, 115, Taiwan
AB: A simulated urban area with size 15x15 km2 representing Chiayi area of central Taiwan can produce up to 3 times more sensible heat flux around noon time than that of a non-urban area. This effect has significant impact on locations of local summer thunderstorms and precipitation over Taiwan western plain by sensitivity tests. We used precipitation and stream gauges in west, east, and northeast of Chiayi area to examine the impact on local hydrological processes including suspended sediment transport. Both monthly mean precipitation and precipitation days have been found greater in the east and northeast of the Chiayi area than the west during the summer periods from 1984 to 2006. In addition, we also found that the decadal mean precipitation has been decreasing in the further east toward the mountain rage since 1980s. This spatial distribution matches the model prediction based on different simulated urban sizes indicating more summer thunderstorms happening before they reaching the mountain range by the effect of heat island. This spatially and temporally increasing trend in precipitation days and total amount of precipitation in the study area has posted a new challenge on the estimation of suspended sediment transport.
DE: 1834 Human impacts
SC: Hydrology [H]
MN: 2007 Fall Meeting