HR: 0800h
AN: A31A-08 [Abstracts]
TI: Warm Water Pools of the Western Caribbean and Eastern Tropical Pacific: Their Influence on
Intraseasonal Rainfall Regimes and Tropical Storm Activity in Mexico
AU: * Douglas, A V
EM: sonora@creighton.edu
AF: Creighton University, Atmospheric Sciences
2500 California St, Omaha, NE 68178-0110, United States
AU: Englehart, P J
EM: ppajkck@ku.edu
AB:
A dipole in tropical cyclone development between the Caribbean and the eastern tropical Pacific will be examined
relative to its affect on southern Mexican rainfall. With the change over in the AMO and PDO in 1994 and 1998,
respectively, tropical storm genesis has been increasing in the Caribbean while declining in the tropical east
Pacific. This dipole in tropical cyclone development appears to be related to changes in the pre storm season
heat content of the two ocean basins (data Scripps Institution of Oceanography). Preliminary work indicates that if
the Caribbean is warmer than the Pacific by late May the dipole will be accentuated with a pronounced decrease
in tropical storms in the east Pacific with an early and prolonged season in the Caribbean.
In recent years there appears to have been an increase in the intensity and duration of midsummer drought
(Canicula) in Mexico associated with changes in the PDO and AMO. These long term ocean oscillations appear to
control the dipole in the strength of the Caribbean and East Pacific warm pools. Mid summer drought is a
normal occurrence in much of Mexico and Central America, but the intensified droughts of the recent period have
stressed the agricultural community of the region. Based on preliminary work, it appears that the recent
increased frequency of midsummer drought can be linked to a shift in the warmest pool from the East Pacific to
the Caribbean.
DE: 3305 Climate change and variability (1616, 1635, 3309, 4215, 4513)
DE: 3339 Ocean/atmosphere interactions (0312, 4504)
DE: 3354 Precipitation (1854)
DE: 3374 Tropical meteorology
SC: Atmospheric Sciences [A]
MN: 2007 Joint Assembly