POSTER NO: 8 Classification of beach behaviour using singular vectors

ABSTRACT

Please note: All communication regarding this abstract should be sent to the corresponding author, Prof Reeve, at the address above.

It is becoming more widely held that coastal morphodynamics may exTnbit self-organising or chaotic behaviour; a view encouraged by analogy between the fluid dynamical processes of the fields of morphodynamics and meteorology. The latter has the well-known simple model of atmospheric circulation developed by Lorenz (1963) which has been proven to exhibit chaotic behaviour. However, no corresponding model for beach morphodynamics has yet been developed.

Chaos Theory is the term for nonlinear dynamical theory that describes systems whose behaviour is deterministic but highly irregular. The theory shows that simple natural processes can generate very complex behaviour. New methods of data analysis, associated with Chaos Theory, have also been developed specifically to identify order within irregular time series. Many of these methods involve 'phase-space reconstruction', such as the Method of Delays (Broomhead & King 1986). While such methods allow the dynamics of the underlying system to be reconstructed from observations alone they do not provide any guide as to what the governing equations might be. The presence, or otherwise, of chaotic behaviour may be inferred, but not proven, from the results of this type of analysis.