To understand the magnitude of the recent floods that hit Manila and northern Luzon in the wake of TS Ondoy (Ketsana), it pays to look at the historical record of flooding in the Philippines. There had been major flooding events before and some have been recorded in Spanish friar accounts. Floods regularly inundated Bulacan, Pampanga and Pangasinan as well as the Laguna de Bay area. Marikina was flooded at certain years and this endangered the colony's food security that residents of these areas had to ask for exemption from the hated colonial tribute. Researchers may well try to see if these flooding events are somewhat related to climate events such as El Nino or La Nina. Also they may take note of how long the floods lasted before it subsided. One very documented flood is the one that deluged Manila in November 1943. This is so significant that all writers of WWII memoirs recall it since it marked the start of the worst aspects of the Japanese occupation. The flood deluged part
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