The authors would like to thank Nick Hall, Tercio Ambrizzi, and Jake Badger for help in running the primitive equation model. The comments of Matthew Wheeler, Harry Hendon, and an anonymous reviewer greatly improved the original manuscript. The OLR and NCEP–NCAR reanalysis data were provided through the NOAA Climate Diagnostics Center (http://www.cdc.noaa.gov). The NINO3.4 SST data were from the NOAA/NCEP Climate Prediction Center. This research was supported by the Pan-American Climate Studies Program, under Project GC95-820, sponsored by NOAA’s Office of Global Programs.
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