9:15 AM - 9:30 AM
[AGE28-02] Assessment of flood risk in land subsidence areas: The case of Choushui alluvial fan
Keywords:Climate change, Land subsidence, Hazard, Vulnerability, Risk assessment
For a long time since the industrial revolution, humans have burned enormous amounts of fossil fuels, causing an increase in the concentration of greenhouse gases in the atmosphere, leading to global warming after a long period of accumulation. In addition, changes in atmospheric gas concentrations cause changes in rainfall patterns. As a result, climate change increases the frequency of extreme climate events, such as heavy rains, droughts, and forest fires. In recent years, many abnormal climate events have occurred in Taiwan, including the massive flooding caused by typhoon Fanapi (6-hour cumulative rainfall over 600 mm) in 2010 and the most extensive drought in Taiwan in 2021, both of which caused enormous damage. Many studies have been conducted to assess the risk of abnormal rainfall and drought events, but few studies have been conducted on land subsidence. Therefore, in this study, the land subsidence area of the Choushui alluvial fan was used as the study area, the hazard and vulnerability factors that may affect the area were collected and analyzed. The risk assessment method was established by combining the hazard and vulnerability factors in a risk matrix approach to investigate the disaster risk of the study area when the stratigraphic subsidence area was exposed to an abnormal rainfall event. The above findings can help government agencies to develop area-specific disaster prevention strategies and contingency, enhancing disaster response capabilities in the future.