Discussions with Klaus Weickmann, Brian Hoskins, Adrian Matthews, and Matthew Wheeler provided valuable insights into the observational results of this study. Comments by Ken Gage, Haig Iskenderian, and Leslie Hartten, as well as the careful reading by two reviewers of an earlier draft of the paper led to substantial improvements in interpretation and presentation. This research was supported by the Pan-American Climate Studies (PACS) Program under Project GC95-820, sponsored by NOAA’s Office of Global Programs.
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