We wish to thank Glenn White at NCEP who provided us with the torque and AAM data used in this study, Richard Gross at JPL for the LOD data, and Karen Cady-Pereira and Peter Nelson for archiving the data at AER and providing software support. Gratitude is also expressed to Richard D. Rosen for his thoughtful review of the manuscript, and Klaus Weickmann for his comments on the work. Helpful suggestions were also provided by Lance Bosart and Ed Bracken. Our use of the NCAR data archive is acknowledged. Support for this project was provided by NASA Mission to Planet Earth Awards NAGW-2615 and NAS5-32861 and by the NOAA Climate and Global Change Program under Award NA46GP01212E.
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