Assessing the vulnerability of global tropical coastal cities to flood: Spatio-temporal analysis based on coincide tides and rainfall events

摘要

The coincide condition between the high tide and heavy rainfall event may constitute to severe and prolonged flood. Many coastal cities which having equatorial climate though are facing with those traits and therefore vulnerable to the catastrophe. With the recent evidences showing that the tropics is receiving heavier rainfall as a result of global climatic change, there are increasing risk to the coastal cities in facing flood. While there are global analysis on this issue, most are primarily concern with upper latitude with temperate climate cities. Prior to that situation, there is a gap of understanding the phenomena and its spatial extent. In anticipating that issue, we set up two main objectives; I) to determine the frequency of this coincide condition occurred for all tropical cities, 2) to rank the vulnerability of these tropical cities. Rainfall data obtained from the Tropical Rainfall Measuring Mission (TRMM) is used together with the global tidal datasets in performing the analysis. The analysis is conducted at monthly scale with 0.25° operating resolution. The risk classification is defined through the coincide condition of prolonged rainfall and high tides.