Dissipative beach

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Definition of Dissipative beach:
Beach where waves start dissipating their energy (wave breaking) already far from the shoreline.
This is the common definition for Dissipative beach, other definitions can be discussed in the article


Usual characteristics of dissipative beaches are:

  • Gentle beach slope
  • Fine sandy sediment
  • Steep waves
  • Moderate-to-large tidal amplitude

The so-called Dean parameter [math]\Omega[/math] [1][2] is often used as a measure of wave dissipation on the shoreface. It is defined as

[math]\Omega = \Large \frac{H_s}{wT_p} \normalsize , \qquad(3)[/math]

where [math]H_s[/math] is the offshore significant wave height before breaking, [math]T_p[/math] is the peak spectral wave period and [math]w[/math] is the mean sediment fall velocity. According to Wright and Short (1984) [3] dissipative beaches correspond to [math]\Omega \gt 6 [/math].

See for more details: Shoreface profile.


  1. Gourlay, M. R. 1968. Beach and dune erosion tests. Rep. m935/m936, Delft Hydraul. Lab., Delft
  2. Dean, R.G. 1973. Heuristic models of sand transport in the surf zone. Proc. Conf. Eng. Dynamics in the Surf Zone, Sydney: 208-214
  3. Wright, L.D. and Short, A.D. 1984. Morphodynamic variability of surf zones and beaches: a synthesis. Mar.Geol. 56: 93-118