Bagtasa, G., 2019: Enhancement of summer monsoon rainfall by tropical cyclones in northwestern Philippines. J. Meteor. Soc. Japan, 97,
Early Online Release Graphical Abstract with highlights
Plain Language Summary: The Philippines’ location makes it vulnerable to the hazards of tropical cyclones forming in the western North Pacific Ocean. This study looks at how distant tropical cyclones can cause heavy rainfall in the northwestern region of the Philippines. Though almost all heavy rainfall events in that region of the Philippines are caused by tropical cyclones during summer season, only about 10% are due to tropical cyclones directly hitting the area. 90% of heavy rain events are due to cyclones that are hundreds of kilometers away, particularly, around the region between Okinawa and Luzon. The presence of tropical cyclones are able affect the monsoon circulation leading to heavy rainfall along the northwestern coasts of the Philippines.
- Most tropical cyclones that bring heavy rainfall to northwestern Philippines are distant TCs.
- TCs near the line segment connecting Okinawa and Luzon can lead to the formation of the “moisture conveyor belt” where high amounts of water vapor move along a narrow path in South China Sea and the Philippines.
- Recent changes in TC tracks have led to more heavy precipitation event days due to this TC monsoon interaction.