Large increasing trend of tropical cyclone rainfall in Taiwan and the roles of terrain
Journal
Journal of Climate
Journal Volume
26
Journal Issue
12
Pages
4138-4147
Date Issued
2013
Author(s)
Abstract
Taiwan, which is in the middle of one of the most active of the western North Pacific Ocean's tropical cyclone (TC) zones, experienced a dramatic increase in typhoon-related rainfall in the beginning of the twenty-first century. This record-breaking increase has led to suggestions that it is the manifestation of the effects of global warming. With rainfall significantly influenced by its steep terrain, Taiwan offers a natural laboratory to study the role that terrain effects may play in the climate change of TC rainfall. Here, it is shown that most of the recently observed large increases in typhoon-related rainfall are the result of slow-moving TCs and the location of their tracks relative to the meso-a-scale terrain. In addition, stronger interaction between the typhoon circulation and southwest monsoon wind surges after the typhoon center moves into the Taiwan Strait may cause a long-term trend of increasing typhoon rainfall intensity, which is not observed before the typhoon center exits Taiwan. The variation in the location of the track cannot be related to the effects of global warming on western North Pacific TC tracks reported in the literature. The weaker steering flow and the stronger monsoon-TC interaction are consistent with the recently discovered multidecadal trend of intensifying subtropical monsoon and tropical circulations, which is contrary to some theoretical and model projections of global warming. There is also no evidence of a positive feedback between global warming- related water vapor supply and TC intensity, as the number of strong landfalling TCs has decreased significantly since 1960 and the recent heavy rainfall typhoons are all of weak-to-medium intensity. © 2013 American Meteorological Society.
Subjects
Climate change; Extreme events; Hurricanes/typhoons; Interdecadal variability; Orographic effects; Precipitation
SDGs
Other Subjects
Extreme events; Hurricanes/typhoons; Inter-decadal variability; Natural laboratories; Orographic effects; Southwest monsoon; Water vapor supply; Western North Pacific; Atmospheric thermodynamics; Climate change; Global warming; Hurricanes; Landforms; Precipitation (chemical); Rain; atmospheric circulation; climate change; decadal variation; extreme event; global warming; hurricane; mesoscale meteorology; monsoon; orographic effect; precipitation intensity; terrain; tropical cyclone; typhoon; water vapor; Pacific Ocean; Pacific Ocean (North); Taiwan; Taiwan Strait
Type
journal article