We gratefully acknowledge the following: Mr. Z. Fang helped with the graphics (Figs. 1, 4, and 8) and Ms. Z. Fan prepared the SST data. The constructive comments and suggestions from Dr. John Knaff and another anonymous reviewer as well as Dr. H. von Storch have contributed significantly to the improvement of the manuscript. RW was supported by an NSERC fellowship from the Environment Canada. He is particularly thankful to the RPN (Recherche en Prévision Numérique) for providing an excellent working condition and technical supports. BW is supported by NOAA GOALS and PACS program. Part of the work was done during RW’s visit to the University of Hawaii whose hospitality is gratefully acknowledged. This is the School of Ocean and Earth Science and Technology publication No. 5245 and International Pacific Research Center publication No. 52.
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