The authors thank Mark Cane, Dave DeWitt, Simon Mason, Tony Barnston, Kevin Trenberth, and two anonymous reviewers for comments on this work. The authors are supported by a cooperative agreement from the National Oceanic and Atmospheric Administration (NOAA) NA07GP0213. The views expressed herein are those of the authors and do not necessarily reflect the views of NOAA or any of its subagencies.
Barnston, A. G., , M. Chelliah, , and S. B. Goldenberg, 1997: Documentation of a highly ENSO-related SST region in the equatorial Pacific. Atmos.–Ocean, 35 , 367–383.
Barnston, A. G., , S. J. Mason, , L. Goddard, , D. G. DeWitt, , and S. E. Zebiak, 2003: Increased automation and use of multimodel ensembling in seasonal climate forecasting at the IRI. Bull. Amer. Meteor. Soc., 84 , 1783–1796.
Benson, C., , and E. J. Clay, 1998: The impact of drought on sub-saharan African economies: A preliminary examination. The World Bank Tech. Paper 401, 80 pp.
Bouma, M. J., , R. S. Kovats, , S. A. Goubet, , J. S. H. Cox, , and A. Haines, 1997: Global assessment of El Niño’s disaster burden. Lancet, 350 , 1435–1438.
Branković, Č, , and T. N. Palmer, 2000: Seasonal skill and predictability of ECMWF PROVOST ensembles. Quart. J. Roy. Meteor. Soc., 126 , 2035–2067.
Dilley, M., , and B. N. Heyman, 1995: ENSO and disaster: Droughts, floods and El Niño/Southern Oscillation warm events. Disasters, 19 , 181–193.
Eischeid, J. K., , H. G. Diaz, , R. S. Bradley, , and P. D. Jones, 1991: A comprehensive precipitation data set for global land areas. U.S. Department of Energy Carbon Dioxide Research Division Tech. Rep. TR051, 81 pp.
EM-DAT, cited 2003: The OFDA/CRED international disaster database. Université Catholique de Louvain. [Available online at http://www.cred.be.].
Goddard, L., , and N. E. Graham, 1999: The importance of the Indian Ocean for simulating rainfall anomalies over eastern and southern Africa. J. Geophys. Res., 104 , 19099–19116.
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 predictions. Int. J. Climatol., 21 , 1111–1152.
Gray, W. M., 1984: Atlantic seasonal hurricane frequency. Part I: El Niño and 30 mb quasi-biennial oscillation influences. Mon. Wea. Rev., 112 , 1649–1668.
Hack, J. J., , J. T. Kiehl, , and J. W. Hurrell, 1998: The hydrologic and thermodynamic characteristics of the NCAR CCM3. J. Climate, 11 , 1179–1206.
Hulme, M., 1992: A 1951–80 global land precipitation climatology for the evaluation of General Circulation Models. Climate Dyn., 7 , 57–72.
Hulme, M., 1994: Validation of large-scale precipitation fields in general circulation models. Global Precipitations and Climate Change, M. Desbois and F. Desalmand, Eds., NATO ASI Series, Springer-Verlag, 387–406.
Kumar, A., , and M. P. Hoerling, 1998: Annual cycle of Pacific–North American seasonal predictability associated with different phases of ENSO. J. Climate, 11 , 3295–3308.
Landsea, C. W., , and J. A. Knaff, 2000: How much skill was there in forecasting the very strong 1997–98 El Niño? Bull. Amer. Meteor. Soc., 81 , 2107–2120.
Mason, S. J., 2004: On using “climatology” as a reference strategy in the Brier and ranked probability skill scores. Mon. Wea. Rev., 132 , 1891–1895.
McPhaden, M. J., and Coauthors, 1998: The Tropical Ocean-Global Atmosphere observing system: A decade of progress. J. Geophys. Res., 103 , 14169–14240.
Penland, C., , and L. Matrosova, 1998: Prediction of tropical Atlantic sea surface temperatures using linear inverse modeling. J. Climate, 11 , 483–496.
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.
Robertson, A. W., , U. Lall, , S. E. Zebiak, , and L. Goddard, 2004: Improved combination of multiple atmospheric GCM ensembles for seasonal prediction. Mon. Wea. Rev., 132 , 2732–2744.
Roeckner, E., and Coauthors, 1996: The atmospheric general circulation model ECHAM4: Model description and simulation of present-day climate. Max-Planck-Institüt für Meteorologie Rep. 218, 90 pp.
Ropelewski, C. F., , and M. S. Halpert, 1987: Global and regional scale precipitation patterns associated with the El Niño/Southern Oscillation. Mon. Wea. Rev., 115 , 1606–1626.
Ropelewski, C. F., , and M. S. Halpert, 1989: Precipitation patterns associated with the high index phase of the Southern Oscillation. J. Climate, 2 , 268–284.
Sponberg, K., 1999: Navigating the numbers of climatological impact. Compendium of Climatological Impacts, University Corporation for Atmospheric Research, Vol. 1, National Oceanic and Atmospheric Administration, Office of Global Programs, 13 pp. [Available online at http://www.cip.noaa.gov/docs/navimpact.pdf.].
Thomson, M. C., , K. Abayomi, , A. G. Barnston, , M. Levy, , and M. Dilley, 2003: El Niño and drought in southern Africa. Lancet, 361 , 437–438.
Trenberth, K. E., , G. W. Branstator, , D. Karoly, , A. Kumar, , N-C. Lau, , and C. F. Ropelewski, 1998: Progress during TOGA in understanding and modelling global teleconnections associated with tropical sea surface temperatures. J. Geophys. Res., 103 , 14291–14324.
UCAR, 1994: El Niño and climate prediction. Reports to the Nation on our Changing Planet, UCAR, No. 3, 25 pp.
Wallace, J. M., , E. M. Rasmusson, , T. P. Mitchell, , V. E. Kousky, , E. S. Sarachik, , and H. von Storch, 1998: On the structure and evolution of ENSO-related climate variability in the tropical Pacific: Lessons from TOGA. J. Geophys. Res., 103 , 14241–14259.
Weiher, R. F., Ed. 1999: Improving El Niño forecasting: The potential benefits. U.S. Dept. of Commerce, National Atmospheric and Oceanic Administration, 57 pp. [Available online at http://www.publicaffairs.noaa.gov/worldsummit/pdfs/improving.pdf].