Research Center for Environmental Changes, Academia Sinica  

10am, 4 Feb, 2015

Room 101, Keyan Building, IAP  

Abstract 

Significant increases in precipitation intensity, as a result of increases of heavy precipitation and/or decreases of light precipitation have been reported over widespread regions of the globe. The increase in precipitation intensity has been attributed to global warming. Trenberth et al. [2003] hypothesized that the precipitation intensity should increase at about the same rate as atmospheric moisture which increases at about 7% K-1 according to the Clausius-Clapeyron equation. They argued that the increase in heavy rainfall could even exceed the 7% K-1 because additional latent heat released from the increased water vapor could invigorate the storms. An invigorated storm could remove moisture by more than 7% K-1 from the atmosphere. Heavy precipitation in typhoons also has been observed to increase significantly in Taiwan. In this work, we analyze precipitation intensity of global typhoons and find that the top 10% heavy precipitation of global typhoons increases by 200% for each degree increase in global temperature, yet the bottom 50% light precipitation stays constant. The relative contributions to the observed increase in heavy precipitation in typhoons from various processes will be discussed, including global warming, the translational speed of typhoon, the frequency of typhoon, and the intensity of typhoon.