Location
East-West Center, University of Hawai'i at Manoa (Honolulu, Hawai'i)
Start Date
18-10-2012 12:10 PM
End Date
18-10-2012 12:30 PM
Document Type
Event
Description
Two sets of TTL boundary definitions have been proposed in the literature. One uses the static stability structure (Gettelman and Foster, 2002) and the other uses the radiative forcing mass flux criterion (Fu et al., 2007; Fueglistaler et al., 2009). In this work, we present a method to characterize the TTL boundaries using ozone–water vapor relationship. The result shows that the tracer behavior supports the level of the minimum stability to be the lower boundary of the transition layer and the cold point to be a good proxy of the upper boundary. Using this method, we characterize and compare the behavior of the tropopause transition layer in the Asian summer monsoon region and that of the deep tropics. The Asian summer monsoon region has been known to behave similarly to the TTL in its very high convectively driven tropopause and potentially is an alternative transport pathway for water vapor transport into stratosphere. The comparison between observations in the Asian summer monsoon region (Kunming and Lhasa, China, ~ 25 0 N and 30 0 N, respectively) and the equatorial TTL (Alajuela, Costa Rica, ~10 0 N) shows that the transition layer in the Asian monsoon region is narrower but at higher potential energy levels compared to that observed in the Central American measurements. The possible applications of this method to understanding the global TTL structure will be discussed.
Identification of TTL boundaries using the ozone-water vapor relationship (Powerpoint Slides)
Identification of TTL boundaries using the ozone-water vapor relationship
East-West Center, University of Hawai'i at Manoa (Honolulu, Hawai'i)
Two sets of TTL boundary definitions have been proposed in the literature. One uses the static stability structure (Gettelman and Foster, 2002) and the other uses the radiative forcing mass flux criterion (Fu et al., 2007; Fueglistaler et al., 2009). In this work, we present a method to characterize the TTL boundaries using ozone–water vapor relationship. The result shows that the tracer behavior supports the level of the minimum stability to be the lower boundary of the transition layer and the cold point to be a good proxy of the upper boundary. Using this method, we characterize and compare the behavior of the tropopause transition layer in the Asian summer monsoon region and that of the deep tropics. The Asian summer monsoon region has been known to behave similarly to the TTL in its very high convectively driven tropopause and potentially is an alternative transport pathway for water vapor transport into stratosphere. The comparison between observations in the Asian summer monsoon region (Kunming and Lhasa, China, ~ 25 0 N and 30 0 N, respectively) and the equatorial TTL (Alajuela, Costa Rica, ~10 0 N) shows that the transition layer in the Asian monsoon region is narrower but at higher potential energy levels compared to that observed in the Central American measurements. The possible applications of this method to understanding the global TTL structure will be discussed.
