Drifter dispersion in the Adriatic Sea : Lagrangian data and chaotic model

• We analyze characteristics of drifter trajectories from the Adriatic Sea with recently introduced nonlinear dynamics techniques. We discuss how in quasi-enclosed basins, relative dispersion as a function of time, a standard analysis tool in this context, may give a distorted picture of the dynamics. We further show that useful information may be obtained by using two related non-asymptotic indicators, the Finite-Scale Lyapunov Exponent (FSLE) and the Lagrangian Structure Function (LSF), which both describe intrinsic physical properties at a given scale. We introduce a simple chaotic model for drifter motion in this system, and show by comparison with the model that Lagrangian dispersion is mainly driven by advection at sub-basin scales until saturation sets in.

Keyword

oceanography general(marginal and semiclosed seas)

oceanography physical (turbulence, diffusion, and mixing processes

upper ocean processes)

meandering jet

surface circulation

diffusion

predictability

turbulence

transport

exchange

currents

times

Publication and Content Type

ref (subject category)

art (subject category)