During the preparation of this and the companion paper (Part 1) the authors benefitted from very useful conversation with many researchers. Among them we wish to particularly thank Prof. I. A. Svendsen, Prof. J. A. Battjes, Dr. R. R. Kerswell and Dr. C. P. Caulfield. The referees are thanked for their comments which have improved the papers presentation. Support from the European Commission Research Grants ERBCHBICT930678, MAS2-CT92 0047 and MAS3-CT97 0081 (SASME) is gratefully acknowledged. We also acknowledge support from the Office of Naval Research in its NICOP program, award no. N00014-97 1 0791 and from the Italian M.U.R.S.T. Grant "Processi vorticosi, turbolenti e caotici - Applicazioni impiantistiche e ambientali".