HR: 09:10h
AN: NG31C-05 INVITED     [Abstracts]
TI: Global Temperature Fluctuations Regulate El Nino Frequency
AU: tsonis, a a
EM: aatsonis@uwm.edu
AF: Department of Mathematical Sciences, Atmospheric Sciences Group, University of Wisconsin-Milwaukee, Milwaukee, WI 43201-0413 United States
AU: elsner, j b
EM: jelsner@garnet.acns.fsu.edu
AF: Department of Geography, Department of Geography, Florida State University,, Tallahassee, FL 32306 United States
AU: * hunt, a g
EM: allen.hunt@wright.edu
AF: Department of Physics and Department of Geology, Wright State University 3640 Colonel Glenn Highway, Dayton, OH 45435 United States
AU: jagger, t h
EM: jelsner@garnet.acns.fsu.edu
AF: Department of Geography, Department of Geography, Florida State University,, Tallahassee, FL 32306 United States
AB: A theory has been proposed recently to explain the relation between global temperature and the El Ni¤o/Southern Oscillation (ENSO). Accordingly1, the frequency of El Ni¤o and La Ni¤a events depends strongly on global temperature tendency. When global temperatures are rising (falling), the onset of an El Ni¤o (La Ni¤a) is much more likely. Moreover the theory asserts that despite an initial warming resulting from El Ni¤o, the regional climate event subsequently acts to reverse the global temperature tendency making ENSO a `safety valve' against a runaway climate system. Here we show how observed and model data lend support to this theory. The analysis shows that temperature increases (decreases) tend to lead El Ni¤o (La Ni¤a). Coherency in the correlation peaks at a significant level at approximately three years (roughly the period of the ENSO "oscillation,") and three months. The latter peak gives a possible interpretation for an El Ni¤o trigger in that it approximates a basin-crossing time for a Kelvin wave. The analyses from SOI, Nino 3 index and GCM's are all comparable.
DE: 3339 Ocean/atmosphere interactions (0312, 4504)
DE: 4522 El Ni¤o
DE: 1610 Atmosphere (0315, 0325)
DE: 1620 Climate dynamics (3309)
SC: Nonlinear Geophysics [NG]
MN: 2004 AGU Fall Meeting