The authors would like to thank S. G. H. Philander, S.-P. Xie, W. Kessler, and G. Holland for their insightful comments. Two anonymous reviewers have provided thorough review and valuable comments, which helped improve the manuscript. Thanks are also extended to Mr. L. Wu and Mr. X. Fu for their assistance in processing data and preparing the manuscript. Support from the NOAA/PACS Program and ONR/Marine Meteorology Program under Grant 0014-95-1-1230 are greatly appreciated.
Battisti, D. S., and A. C. Hirst, 1989: Interannual variability in the tropical atmosphere–ocean system: Influence of the basic state and ocean geometry. J. Atmos. Sci.,46, 1678–1712.
Bjerknes, 1969: Atmospheric teleconnection from the equatorial pacific. Mon. Wea. Rev.,97, 526–535.
Budyko, M. I., and D. H. Miller, 1974: Climate and Life. Academic Press, 508 pp.
Chang, P., 1996: The role of the dynamic ocean–atmosphere interactions in the tropical seasonal cycle. J. Climate,9, 2973–2985.
——, and S. G. H. Philander, 1994: A coupled ocean–atmosphere instability of relevance to seasonal cycle. J. Atmos. Sci.,51, 3627–3648.
Charney, J. G., 1971: Tropical cyclogenesis and the formation of the intertropical convergence zone. Mathematical Problems of Geophysical Fluid Dynamics, W. H. Reid, Ed., Lectures in Applied Mathematics, Vol. 13, Amer. Math. Soc., 355–368.
Davey, M. K., and Gill, A. E., 1987: Experiments on tropical circulation with a simple moist model. Quart. J. Roy. Meteor. Soc.,113, 1237–1269.
Dijkstra, H. A., and J. D. Neelin, 1995: Ocean–atmospheric interaction and the tropical climatology. Part II: Why the Pacific cold tongue is in the east. J. Climate,8, 1343–1359.
Giese, B. S., and J. A. Carton, 1994: The seasonal cycle in a coupled ocean–atmosphere model. J. Climate,7, 1208–1217.
Gill, A. E., 1980: Some simple solutions for heat-induced tropical circulation. Quart. J. Roy. Meteor. Soc.,106, 447–462.
Held, I. M., and A. Y. Hou, 1980: Nonlinear axially symmetric circulations in a nearly inviscid atmosphere. J. Atmos. Sci.,37, 515–533.
Holton, J. R., J. M. Wallace, and J. A. Young, 1971: On boundary layer dynamics and the ITCZ. J. Atmos. Sci.,28, 275–180.
Horel, J. D., 1982: On the annual cycle of the tropical Pacific atmosphere and ocean. Mon. Wea. Rev.,110, 1863–1878.
Jin, F.-F., 1996: Tropical ocean–atmosphere interaction, the Pacific cold tongue, and the El Nino–Southern Oscillation. Science,274, 76–78.
Li, T., 1997: Air–sea interaction of relevance to the ITCZ: Analysis of coupled instability and experiments in a hybrid coupled GCM. J. Atmos. Sci.,54, 134–147.
——, and B. Wang, 1994: A thermodynamic equilibrium climate model for monthly mean surface winds and precipitation over the tropical Pacific. J. Atmos. Sci.,51, 1372–1385.
Lindzen, R. S., and S. Nigam, 1987: On the role of sea surface temperature gradients in forcing low level winds and convergence in the tropics. J. Atmos. Sci.,44, 2440–2458.
——, and A. Y. Hou, 1988: Hadley circulations for zonally averaged heating centered off the equator. J. Atmos. Sci.,45, 2416–2427.
Liu, Z., and S.-P. Xie, 1994: Equatorward propagation of coupled air–sea disturbances with application to the annual cycle of the eastern tropical Pacific. J. Atmos. Sci.,51, 3807–3822.
Ma, C.-C., C. R. Mechoso, A. W. Robertson, and A. Arakawa, 1996: Peruvian stratus clouds and the tropical Pacific circulation: A coupled ocean–atmosphere GCM study. J. Climate,9, 1635–1645.
Mitchell, T. P., and J. M. Wallace, 1992: On the annual cycle in equatorial convection and sea surface temperature. J. Climate,5, 1140–1152.
Murakami, T., B. Wang, and S. W. Lyons, 1992: Summer monsoon over the Bay of Bengal and the eastern North Pacific. J. Meteor. Soc. Japan,70, 191–210.
Nigam, S., and Y. Chao, 1996: Evolution dynamics of tropical ocean–atmosphere annual cycle variability. J. Climate,9, 3187–3205.
O’Brien, J. J., and H. E. Hurlburt, 1972: A numerical model of coastal upwelling. J. Phys. Oceanogr.,2, 14–26.
Philander, G., D. Gu, D. Halpern, G. Lambert, N.-C. Lau, T. Li, and R. C. Pacanowski, 1996: Why the ITCZ is mostly north of the equator. J. Climate,9, 2958–2972.
Sadler, J. C., M. A. Lander, A. M. Hori, and K. Oda, 1987: Pacific Ocean. Vol. 1. Tropical Marine Climate Atlas. Rep. UHMET 87-02, Department of Meteorology, University of Hawaii, 27 pp.
Sverdrup, H., 1947: Wind-driven currents in a baroclinic ocean, with application to the equatorial currents of the eastern Pacific. Natl. Acad. Sci.,33, 318–326.
Waliser, D. E., and R. C. J. Somerville, 1994: Preferred latitudes of the intertropical convergence zone. J. Atmos. Sci.,51, 1619–1639.
Wang, B., 1988: Dynamics of tropical low-frequency waves: An analysis of the moist Kelvin wave. J. Atmos. Sci.,45, 2051–2065.
——, 1994: On the annual cycle in the eastern-central Pacific. J. Climate,7, 1926–1942.
——, and T. Li, 1993: A simple tropical atmosphere model of relevance to short-term climate variations. J. Atmos. Sci.,50, 260–284.
——, and ——, 1994: Convective interaction with boundary layer dynamics in the development of a tropical intraseasonal system. J. Atmos. Sci.,51, 1386–1400.
——, and Z. Fang, 1996: Chaotic oscillation of the tropical climate:A dynamic system theory for ENSO. J. Atmos. Sci.,53, 2786–2802.
Xie., P., and P. Arkin, 1996: Analysis of global monthly precipitation using gauge observations, satellite estimates, and numerical model predictions. J. Climate,9, 840–858.
Xie, S.-P., 1996: Westward propagation of latitudinal asymmetry in a coupled ocean–atmosphere model. J. Atmos. Sci.,53, 3236–3250.
——, 1997: Unstable transition of the tropical climate to an equatorially asymmetric state in a coupled ocean–atmosphere model. Mon. Wea. Rev.,125, 667–679.
——, and S. G. H. Philander, 1994: A coupled ocean–atmosphere model of relevance to the ITCZ in the eastern Pacific. Tellus,46A, 340–350.
Zebiak, S. E., and M. A. Cane, 1987: A model ENSO. Mon. Wea. Rev.,115, 2262–2278.