ABSTRACT
Acknowledgements I would like to thank Robert M. Kerr, Peter Fox and Chin-Hoh Moeng for inviting me to this meeting. I am also grateful to Jack Herring, Greg Holloway, Pascale Lelong, Marcel Lesieur, Doug Lilly, Andrew Majda, Olivier Metais, Jim Riley, Geoff Vallis, and Tom Warn for many interesting exchanges on this topic.
