Abstract
This paper describes the near-surface transport properties and Lagrangian statistics in the Adriatic semi-enclosed basin using synthetic drifters. Lagrangian transport models were used to simulate synthetic trajectories from the mean flow fields obtained by the Massachusetts Institute of Technology general circulation model (MITgcm), implemented in the Adriatic from October 2006 until December 2008. In particular, the surface circulation properties in two contrasting years (2007 had a mild winter and cold fall, while 2008 had a normal winter and hot summer) are compared here. In addition, the Lagrangian statistics for the entire Adriatic Basin after removing the Eulerian mean circulation for numerical particles were calculated. The results indicate that the numerical particles were slower in this simulation when compared with the real drifters. This is because of the reduced energetic flow field generated by the MIT general circulation model during the selected years. The numerical results showed that the balanced effects of the wind-driven recirculation in the northernmost area(which would be a sea response to the Bora wind field) and the Po River discharge cause the residence times to be similar during the two selected years (182 and 185 days in 2007 and 2008, respectively). Furthermore, the mean angular momentum, diffusivity, and Lagrangian velocity covariance values are smaller than in the real drifter observations, while the maximum Lagrangian integral time scale is the same.
Highlights
Falco et al [1] mentioned that the residence time values for real drifters in the Adriatic are between 70 and 90 days because of the finite lifetime of the drifters, while numerical particles simulated by the model suggested a correct value of 200 days
De Dominicis et al [8] quantified the sub-grid scale diffusion of the Lagrangian models written in terms of horizontal eddy diffusivity. They used a large database of drifters released in different regions of the Mediterranean Sea; the Lagrangian sub-grid-scale diffusion was computed by considering different regimes when averaging statistical quantities. They simulated the real drifters using a trajectory model forced by Ocean General Circulation Model (OGCM) currents to investigate how the Lagrangian properties are reproduced by the simulated trajectories
This study indicates that Lagrangian analysis is a powerful way to analyze the output of ocean circulation models and other ocean velocity data, considering that the Lagrangian approach plays an important role in many practical areas, including water quality management, planning for pollutant discharge, sediment tracking near river or stream mouths, and prevention of rivermouth clogging
Summary
Over the last 40 years, the dynamical characteristics of oceanic flows have been widely analyzed using Lagrangian approaches. Carlson et al [7] used surface drifters and virtual particles to investigate transport between seven coastal regions in the central and southern Adriatic Sea to estimate the degree to which these regions function as a network They mentioned that southeasterly Sirocco winds can drive eastward cross-Adriatic transport from the Italian coast near the Gargano promontory to the Dalmatian Islands in Croatia, while disrupting alongshore transport on the west coast. They used a large database of drifters released in different regions of the Mediterranean Sea; the Lagrangian sub-grid-scale diffusion was computed by considering different regimes when averaging statistical quantities They simulated the real drifters using a trajectory model forced by Ocean General Circulation Model (OGCM) currents to investigate how the Lagrangian properties are reproduced by the simulated trajectories. Other applications of the Lagrangian technique have been extensively discussed by [9,10,11,12,13,14,15,16]
Sign-in/Register to view highlights & summary Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
