The first author was supported by the NASA Earth Systems Science Graduate Fellowship and the NOAA Global Change Postdoctoral Fellowship. The other authors were funded by NOAA-CICAR NA03OAR432017. Helpful discussions with Peter Gent, Joe Tribbia, and Martin Visbeck are gratefully acknowledged, as are comments from Gerrit Burgers and an anonymous reviewer.
Barnston, A., M. Glantz, and Y. He, 1999: Predictive skill of statistical and dynamical climate models in SST forecasts during the 1997–98 El Niño episode and the 1998 La Niña onset. Bull. Amer. Meteor. Soc., 80 , 217–243.
Batstone, C., and H. Hendon, 2005: Stochastic variability associated with ENSO and the role of the MJO. J. Climate, 18 , 1773–1789.
Battisti, D., and A. Hirst, 1989: Interannual variability in a tropical atmosphere–ocean model: Influence of the basic state, ocean geometry and nonlinearity. J. Atmos. Sci., 46 , 1687–1712.
Cane, M., A. Kaplan, R. Miller, B. Tang, E. Hackert, and A. Busalacchi, 1996: Mapping tropical Pacific sea level: Data assimilation via a reduced state space Kalman filter. J. Geophys. Res., 101 , 22599–22617.
Cañizares, R., A. Kaplan, M. Cane, and D. Chen, 2001: Use of data assimilation via linear low-order models for the initialization of El Niño-Southern Oscillation predictions. J. Geophys. Res., 106 , 30947–30959.
Chen, D., S. Zebiak, M. Cane, and A. Busalacchi, 1997: Initialization and predictability of a coupled ENSO forecast model. Mon. Wea. Rev., 125 , 773–788.
Chen, D., M. Cane, S. Zebiak, R. Canizares, and A. Kaplan, 2000: Bias correction of an ocean-atmosphere coupled model. Geophys. Res. Lett., 27 , 2585–2588.
Chen, D., M. Cane, A. Kaplan, S. Zebiak, and D. Huang, 2004: Predictability of El Niño over the past 148 years. Nature, 428 , 733–736.
Cheney, R., L. Miller, R. Agreen, N. Doyle, and J. Lillibridge, 1994: TOPEX/Poseidon: The 2-cm solution. J. Geophys. Res., 99 , 24555–24564.
daSilva, A., A. Young, and S. Levitus, 1994: Algorithms and Procedures. Vol. 1, Atlas of Surface Marine Data, NOAA Atlas NESDIS 6, 83 pp.
Deser, C., A. Capotondi, R. Saravanan, and A. Phillips, 2005: Tropical Pacific and Atlantic climate variability in CCSM3. J. Climate, 19 , 2451–2481.
Evans, M., and A. Kaplan, 2004: The Pacific sector Hadley and Walker Circulations in historical marine wind analyses. The Hadley Circulation: Present, Past and Future, H. F. Diaz and R. S. Bradley, Eds., Kluwer Academic, 239–258.
Fan, Y., M. Allen, D. L. T. Anderson, and M. A. Balmaseda, 2000: How predictability depends on the nature of uncertainty in initial conditions in a coupled model of ENSO. J. Climate, 13 , 3298–3313.
Fedorov, A., S. Harper, S. Philander, B. Winter, and A. Wittenberg, 2003: How predictable is El Niño? Bull. Amer. Meteor. Soc., 84 , 911–919.
Flugel, M., P. Chang, and C. Penland, 2004: The role of stochastic forcing in modulating ENSO predictability. J. Climate, 17 , 3125–3140.
Jochum, M., and R. Murtugudde, 2004: Internal variability of the tropical Pacific Ocean. Geophys. Res. Lett., 31 .L14309, doi:10.1029/2004GL020488.
Kaplan, A., M. Cane, Y. Kushnir, A. Clement, M. Blumenthal, and B. Rajagopalan, 1998: Analysis of global sea surface temperature 1856–1991. J. Geophys. Res., 103 , 18567–18589.
Kaplan, A., Y. Kushnir, and M. Cane, 2003: Reduced space approach to the optimal analysis interpolation of historical marine observations: Accomplishments, difficulties, and prospects. Advances in the Applications of Marine Climatology: The Dynamic Part of the WMO Guide to the Applications of Marine Climatology. Tech. Rep. WMO/TD-1081, World Meteorological Organization, Geneva, Switzerland, 99–216.
Kaplan, M., M. Cane, D. Chen, D. Witter, and R. Cheney, 2004: Small-scale variability and model error in tropical Pacific sea level. J. Geophys. Res., 109 .CO2001, doi:10.1029/2002JC001743.
Karspeck, A., 2004: Predictability of ENSO on interannual and decadal timescales. Ph.D. dissertation, Lamont-Doherty Earth Observatory, Columbia University, 181 pp. [Available from ProQuest Digital Dissertations AAT3138346 at http://wwwlib.umi.com/dxweb/.].
Karspeck, A., R. Seager, and M. Cane, 2004: Predictability of tropical Pacific decadal variability in an intermediate model. J. Climate, 17 , 2842–2850.
Kirtman, B., J. Shukla, M. Balmaseda, N. Graham, C. Penland, Y. Xue, and S. Zebiak, 2001: Current status of ENSO forecast skill. Tech. Rep. 56, CLIVAR Working Group on Seasonal to Interannual Prediction, 26 pp.
Kleeman, R., and A. Moore, 1999: A new method for determining the reliability of dynamical ENSO predictions. Mon. Wea. Rev., 127 , 694–705.
McPhaden, M., 2003: Tropical Pacific Ocean heat content variations and ENSO persistence barriers. Geophys. Res. Lett., 30 .1480, doi:10.1029/2003GL016872.
Orrell, D., L. Smith, J. Barkmeijer, and T. Palmer, 2001: Model error in weather forecasting. Nonlinear Processes Geophys., 8 , 357–371.
Penland, C., and T. Magorian, 1993: Prediction of Niño 3 sea surface temperatures using linear inverse modeling. J. Climate, 6 , 1067–1076.
Penland, C., and P. Sardeshmukh, 1995: The optimal growth of tropical sea surface temperature anomalies. J. Climate, 8 , 1999–2024.
Stricherz, J., D. Legler, and J. O’Brien, 1997: TOGA pseudostress atlas, 1985–1994: II, tropical Pacific Ocean. COAPS Rep. 97-2, Center for Ocean–Atmosphere Prediction Studies, Tallahassee, FL, 155 pp.
Swanson, K., T. N. Palmer, and R. Vautard, 2000: Observational error structures and the value of advanced assimilation techniques. J. Atmos. Sci., 57 , 1327–1340.
Thompson, C., and D. Battisti, 2000: A linear stochastic dynamical model of ENSO. Part I: Model development. J. Climate, 13 , 2818–2832.
Vecchi, G., and D. Harrison, 2000: Tropical Pacific sea surface temperature anomalies, El Niño, and equatorial westerly wind events. J. Climate, 13 , 1814–1830.
Xue, Y., M. Cane, and S. Zebiak, 1997a: Predictability of a coupled model of ENSO using singular vector analysis. Part I: Optimal growth in seasonal background and ENSO cycles. Mon. Wea. Rev., 125 , 2053–2056.
Xue, Y., M. Cane, and S. Zebiak, 1997b: Predictability of a coupled model of ENSO using singular vector analysis. Part II: Optimal growth and forecast skill. Mon. Wea. Rev., 125 , 2057–2073.