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

G. Lacorata (1, 2) , E. Aurell (3) , A. Vulpiani (4)

1 Dipartimento di Fisica [L'Aquila]
2 Dipartimento di Fisica
3 Department of Mathematics
4 Istituto Nazionale Fisica della Materia

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.

Domaines: Océan, Atmosphère; Sciences de la Terre

G. Lacorata, E. Aurell, A. Vulpiani. Drifter dispersion in the Adriatic Sea: Lagrangian data and chaotic model. Annales Geophysicae, 2001, 19 (1), pp.121-129. ⟨hal-00318815⟩