Characterizing Spatial Patterns and Climatology Trends using Monthly Rainfall Rates in Manila, Philippines

Manila, serves as the Philippines capital of Luzon, and is located in the northern archipelago of the islands. Faced with complex topography, flooding within Manila is a major concern for this urbanized-metropolis. This region's watershed is impacted by several bodies of water including the South China Sea, the Manila Bay, the Bay of Laguna, and the Pasig River which runs through the city center. In addition, the region is plagued with persistent rainfall during the onset of the Western North Pacific Summer Monsoon (WNPSM). Since typhoon season in the Philippines typically occurs during the months of June through December and also coincides with the duration of the WNPSM, it is critical to better characterized precipitation rates during this time period to improve flood monitoring and its response to increased rainfall which will enhance prediction systems for areas inclined to local flooding. This study will address spatial patterns and climatology trends in monthly rainfall rates during the typhoon season in Manila. Images acquired from the 3B-43 Tropical Rainfall Measuring Mission (TRMM) from NASA, which provides a monthly best-estimate precipitation rate, were mapped for the months associated with the onset of the WNPSM from 1998 to 2010. With the use of GIS and statistical analysis, variations in monthly precipitation rates will be discussed to depict significant changes in climatology and spatial trends which will provide more accurate precipitation forecasting within Manila.