We thank Xiaofeng Gong (IRI) for making retrospective forecasts with the ECHAM4.5 model and all the individuals and institutions who make their model data available to the IRI. Mark Lindeman and Maria Anulacion of the Production Estimates and Crop Assessment Division, USDA, kindly provided station data and precipitation estimates. We thank Benno Blumenthal for the IRI Data Library. Comments, suggestions, and corrections from Simon Mason, Marty Hoerling, and two anonymous reviewers improved the quality of this paper. IRI is supported by its sponsors and NOAA Office of Global Programs Grant NA07GP0213.
Agrawala, S., , M. Barlow, , H. Cullen, , and B. Lyon, 2001: The drought and humanitarian crisis in Central and Southwest Asia: A climate perspective. Special Rep. 01-11, IRI, Palisades, NY, 24 pp. [Available online at http://iri.columbia.edu/outreach/publication/irireport/SWAsia/index.html.].
Bacmeister, J., , P. Pegion, , S. Schubert, , and M. Suarez, 2000: Atlas of seasonal means simulated by the NSIPP 1 atmospheric GCM. NASA Tech. Rep. NASA/TM-2000-104606, Vol. 17, 194 pp.
Barlow, M., , H. Cullen, , and B. Lyon, 2002: Drought in central and southwest Asia: La Niña, the warm pool, and Indian Ocean precipitation. J. Climate, 15 , 697–700.
Barnett, T. P., , and R. Preisendorfer, 1987: Origins and levels of monthly and seasonal forecast skill for United States surface air temperatures determined by canonical correlation analysis. Mon. Wea. Rev., 115 , 1825–1850.
Barnston, A. G., , and H. M. Van den Dool, 1993: A degeneracy in cross-validated skill in regression-based forecasts. J. Climate, 6 , 963–977.
Barsugli, J. J., , and P. D. Sardeshmukh, 2002: Global atmospheric sensitivity to tropical SST anomalies throughout the Indo-Pacific basin. J. Climate, 15 , 3427–3442.
Chang, C-P., , and K. Lau, 1982: Short-term planetary-scale interactions over the Tropics and midlatitudes during northern winter. Part I: Contrasts between active and inactive periods. Mon. Wea. Rev., 110 , 933–946.
Chang, C-P., , and K. G. Lum, 1985: Tropical-midlatitude interactions over Asia and the western Pacific Ocean during the 1983/84 northern winter. Mon. Wea. Rev., 113 , 1345–1358.
Feddersen, H., , A. Navarra, , and M. N. Ward, 1999: Reduction of model systematic error by statistical correction for dynamical seasonal predictions. J. Climate, 12 , 1974–1989.
Glahn, H. R., , and D. A. Lowry, 1972: The use of model output statistics (MOS) in objective weather forecasting. J. Appl. Meteor., 11 , 1203–1211.
Goddard, L., , S. J. Mason, , S. E. Zebiak, , C. F. Ropelewski, , R. Basher, , and M. A. Cane, 2001: Current approaches to seasonal-to-interannual climate prediction. Int. J. Climatol., 21 , 1111–1152.
Goddard, L., , A. G. Barnston, , and S. J. Mason, 2003: Evaluation of the IRI’s “net assessment” seasonal climate forecasts: 1997–2001. Bull. Amer. Meteor. Soc., 84 , 1761–1781.
Hack, J., , J. Kiehl, , and J. Hurrell, 1998: The hydrologic and thermodynamic characteristics of the NCAR CCM3. J. Climate, 11 , 1179–1206.
Janowiak, J., , and P. Xie, 1999: CAMS–OPI: A global satellite–rain gauge merged product for real-time precipitation monitoring applications. J. Climate, 12 , 3335–3342.
Kinter III, J. L., and Coauthors, 1997: The COLA atmosphere–biosphere general circulation model. Volume 1: Formulation. Tech. Rep. 51, COLA, Calverton, MD, 46 pp.
Landman, W. A., , and L. Goddard, 2002: Statistical recalibration of GCM forecasts over southern Africa using model output statistics. J. Climate, 15 , 2038–2055.
Lau, K. M., , and J. S. Boyle, 1987: Tropical and extratropical forcing of the large-scale circulation: A diagnostic study. Mon. Wea. Rev., 115 , 400–428.
Livezey, R. E., , and W. Chen, 1983: Statistical field significance and its determination by Monte Carlo techniques. Mon. Wea. Rev., 111 , 46–59.
Livezey, R. E., , M. Masutani, , and M. Ji, 1996: SST-forced seasonal simulation and prediction skill for versions of the NCEP/MRF model. Bull. Amer. Meteor. Soc., 77 , 507–517.
Mason, S. J., , and L. Goddard, 2001: Probabilistic precipitation anomalies associated with ENSO. Bull. Amer. Meteor. Soc., 82 , 619–638.
Mason, S. J., , and M. M. Mimmack, 2002: Comparison of some statistical methods of probabilistic forecasting of ENSO. J. Climate, 15 , 8–29.
Mason, S. J., , L. Goddard, , N. E. Graham, , E. Yulaeva, , L. Sun, , and P. A. Arkin, 1999: The IRI seasonal climate prediction system and the 1997/98 El Niño. Bull. Amer. Meteor. Soc., 80 , 1853–1873.
Mo, R., , and D. M. Straus, 2002: Statistical–dynamical seasonal prediction based on principal component regression of GCM ensemble integrations. Mon. Wea. Rev., 130 , 2167–2187.
New, M., , M. Hulme, , and P. Jones, 2000: Representing twentieth-century space–time climate variability. Part II: Development of 1901–96 monthly grids of terrestrial surface climate. J. Climate, 13 , 2217–2238.
Pan, J., , and H. Van den Dool, 1998: Extended-range probability forecasts based on dynamical model output. Wea. Forecasting, 13 , 983–996.
Rajagopalan, B., , U. Lall, , and S. E. Zebiak, 2002: Categorical climate forecasts through regularization and optimal combination of multiple GCM ensembles. Mon. Wea. Rev., 130 , 1792–1811.
Roeckner, E., and Coauthors, 1996: The atmospheric general circulation model ECHAM-4: Model description and simulation of present-day climate. Tech. Rep. 218, Max Planck Institute for Meteorology, Hamburg, Germany, 90 pp.
Ropelewski, C., , and M. Halpert, 1987: Global and regional scale precipitation patterns associated with the El Niño/Southern Oscillation. Mon. Wea. Rev., 115 , 1606–1626.
Ropelewski, C., , and M. Halpert, 1989: Precipitation patterns associated with the high index phase of the Southern Oscillation. J. Climate, 2 , 268–284.
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.
Smith, T. M., , and R. E. Livezey, 1999: GCM systematic error correction and specification of the seasonal mean Pacific–North America region atmosphere from global SSTs. J. Climate, 12 , 273–288.
Ting, M., , and P. D. Sardeshmukh, 1993: Factors determining the extratropical response to equatorial diabatic heating anomalies. J. Atmos. Sci., 50 , 907–918.
Tippett, M. K., , M. Barlow, , and B. Lyon, 2003: Statistical correction of Central Southwest Asia winter precipitation simulations. Int. J. Climatol., 23 , 1421–1433.
Widmann, M., , C. Bretherton, , and E. P. Salathé Jr., 2003: Statistical precipitation downscaling over the northwestern United States using numerically simulated precipitation as a predictor. J. Climate, 16 , 799–816.
Yang, S., , K-M. Lau, , and K-M. Kim, 2002: Variations of the East Asian jet stream and Asian–Pacific–American winter climate anomalies. J. Climate, 15 , 306–325.