Metro Manila urban expansion impact on the heavy rainfall during Tropical Storm Ondoy

Abstract

This study examines the impact of the urban expansion of Metro Manila on the heavy rainfall during Tropical Storm Ondoy. Numerical simulations have been conducted with a mesoscale model using two land cover maps for Metro Manila, representative of the urban cover of the city in the 1970s and at present time. Initial results show an increase of more than 50% in rainfall in some areas due to the urban expansion. A potential mechanism for this rainfall increase is the enhanced convection associated with the warmer urban surface combined with the high moisture during this rainfall event.