This research was supported by Award ATM-9815419 from NSF's Climate Dynamics Division. Thanks to John Lenters and John Chiang for their help in designing the ensemble simulations, and to Lesley Greene, John Chiang, and Brian Belcher for their help in running the GCM integrations. Brian Belcher also prepared the final versions of the figures, and John Chiang wrote the statistical analysis code for the ensembles. Comments of the anonymous reviewers are also appreciated. Graphics were generated using the Grads package developed at COLA.
Aceituno, P., 1988: On the functioning of the Southern Oscillation in the South American sector. Part I: Surface climate. Mon. Wea. Rev, 116 , 505–524.
Arkin, P. A., 1982: The relationship between interannual variability in the 200 mb tropical wind field and the Southern Oscillation. Mon. Wea. Rev, 110 , 1393–1404.
Blackmon, M. L., , J. E. Geisler, , and E. J. Pitcher, 1983: A general circulation model study of January climate anomaly patterns associated with interannual variation of equatorial Pacific sea surface temperatures. J. Atmos. Sci, 40 , 1410–1425.
Branstator, G. W., 1983: Horizontal energy propagation in a barotropic atmosphere with meridional and zonal structure. J. Atmos. Sci, 40 , 1689–1708.
Cook, K. H., 2000: The South Indian convergence zone and interannual rainfall variability over Southern Africa. J. Climate, 13 , 3789–3804.
Geisler, J. E., , M. L. Blackmon, , G. T. Bates, , and S. Munoz, 1985: Sensitivity of January climate response to the magnitude and position of equatorial Pacific sea surface temperature anomalies. J. Atmos. Sci, 42 , 1037–1049.
Goddard, L., , and N. E. Graham, 1999: Importance of the Indian Ocean for simulating rainfall anomalies over eastern and southern Africa. J. Geophys. Res.-Atmos, 104 , 19 099–19 116.
Held, I. M., , S. W. Lyons, , and S. Nigam, 1989: Transients and the extratropical response to El Niño. J. Atmos. Sci, 46 , 163–174.
Hoerling, M. P., , M-F. Ting, , and A. Kumar, 1995: Zonal flow—Stationary wave relationships during El Niño: Implications for seasonal forcing. J. Climate, 8 , 1838–1852.
Horel, J. D., , and J. M. Wallace, 1981: Planetary scale atmosphere phenomena associated with the Southern Oscillation. Mon. Wea. Rev, 109 , 813–829.
Hoskins, B. J., , and D. E. Karoly, 1981: The steady linear response of a spherical atmosphere to thermal and orographic forcing. J. Atmos. Sci, 38 , 1179–1196.
Hoskins, B. J., , and T. Ambrizzi, 1993: Rossby wave propagation on a realistic longitudinally varying flow. J. Atmos. Sci, 50 , 1661–1671.
Hsu, H-H., , and S-H. Lin, 1992: Global teleconnections in the 250-mb streamfunction field during the Northern Hemisphere winter. Mon. Wea. Rev, 120 , 1169–1190.
Kiladis, G. N., , and H. F. Diaz, 1989: Global climate anomalies associated with extremes in the Southern Oscillation. J. Climate, 2 , 1069–1090.
Kok, C. J., , and J. D. Opsteegh, 1985: On the possible causes of anomalies in the seasonal mean circulation pattern during the 1982–83 El Niño event. J. Atmos. Sci, 42 , 677–694.
Lau, N-C., , and E. O. Holopainen, 1984: Transient eddy forcing of the time mean flow as identified by geopotential tendencies. J. Atmos. Sci, 41 , 313–328.
Lau, N-C., , and M. J. Nath, 1990: A general circulation model study of the atmosphere response to extratropical SST anomalies observed in 1950–1979. J. Climate, 3 , 965–989.
Lenters, J. D., , and K. H. Cook, 1999: Summertime precipitation variability over South America: Role of the large-scale circulation. Mon. Wea. Rev, 127 , 409–431.
Matthews, E., 1984: Vegetation, land use, and seasonal albedo data sets: Documentation of archived data tape. NASA Tech. Memo. 86107, 82 pp.
Mintz, Y., , and G. K. Walker, 1993: Global fields of moisture and land surface evapotranspiration derived from observed precipitation and surface air temperature. J. Appl. Meteor, 32 , 1305–1334.
Nicholson, S. E., , and J. Kim, 1997: The relationship of the El Niño–Southern Oscillation to African rainfall. Int. J. Climatol, 17 , 117–135.
Oort, A. H., , and J. J. Yienger, 1996: Observed interannual variability in the Hadley circulation and its connection to ENSO. J. Climate, 9 , 2751–2767.
Rasmusson, E., , and K-C. Mo, 1993: Linkages between 200-mb tropical and extratropical anomalies during the 1986–1989 ENSO. J. Climate, 6 , 595–616.
Ringler, T. D., , and K. H. Cook, 1995: Orographically induced stationary waves: Dependence on latitude. J. Atmos. Sci, 52 , 2548–2560.
Rocha, A., , and I. Simmonds, 1997: Interannual variability of south-eastern African summer rainfall. Part 1. Relationships with air–sea interaction processes. Int. J. Climatol, 17 , 235–265.
Roeschner, E., , J. M. Oberhuber, , A. Bacher, , M. Christoph, , and I. Kirchner, 1996: ENSO variability and the atmospheric response in a global coupled atmosphere–ocean GCM. Climate Dyn, 12 , 737–754.
Ropelewski, C. F., , and M. S. Halpert, 1987: Global and regional scale precipitation patterns associated with El Niño–Southern Oscillation. Mon. Wea. Rev, 115 , 1606–1626.
Sardeshmukh, P. D., , and B. J. Hoskins, 1985: Vorticity balances in the tropics during the 1982–83 El Niño–Southern Oscillation event. Quart. J. Roy. Meteor. Soc, 111 , 261–278.
Sardeshmukh, P. D., , and B. J. Hoskins, 1988: The generation of global rotational flow by steady idealized tropical divergence. J. Atmos. Sci, 45 , 1228–1251.
Shea, D. J., , K. E. Trenberth, , and R. W. Reynolds, 1990: A global monthly sea surface temperature climatology. NCAR Tech. Note NCAR/TN-345+STR, 167 pp. [Available from National Center for Atmospheric Research, P.O. Box 3000, Boulder, CO 80307-3000.].
Sinclair, M. R., , J. A. Renwick, , and J. W. Kidson, 1997: Low-frequency variability of Southern Hemisphere sea level pressure and weather system activity. Mon. Wea. Rev, 125 , 2531–2543.
Ting, M-F., , and I. M. Held, 1990: The stationary wave response to a tropical SST anomaly in an idealized GCM. J. Atmos. Sci, 47 , 2546–2566.
Trenberth, K. E., , G. W. Branstator, , D. Karoly, , A. Kumar, , N-C. Lau, , and C. Ropelewski, 1998: Progress during TOGA in understanding and modeling global teleconnections associated with tropical sea surface temperatures. J. Geophys. Res, 103 , 14 291–14 324.
van Loon, H., , and D. J. Shea, 1985: The Southern Oscillation. Part IV: The precursors south of 15°S to the extremes of the oscillation. Mon. Wea. Rev, 113 , 2063–2074.
Webster, P. J., , and H. R. Chang, 1988: Equatorial energy accumulation and emanation regions: Impacts of a zonally varying basic state. J. Atmos. Sci, 45 , 803–829.