title: The Trapping Index: How to integrate the Eulerian and the Lagrangian approach for the computation of the transport time scales of semi-enclosed basins.
abstract: In this work, we investigated if the Eulerian and the Lagrangian approaches for the computation of the Transport Time Scales (TTS) of semi-enclosed water bodies can be used univocally to define the spatial variability of basin flushing features. The Eulerian and Lagrangian TTS were computed for both simplified test cases and a realistic domain: the Venice Lagoon. The results confirmed the two approaches cannot be adopted univocally and that the spatial variability of the water renewal capacity can be investigated only through the computation of both the TTS. A specific analysis, based on the computation of a so-called Trapping Index, was then suggested to integrate the information provided by the two different approaches. The obtained results proved the Trapping Index to be useful to avoid any misleading interpretation due to the evaluation of the basin renewal features just from an Eulerian only or from a Lagrangian only perspective.
authors.affiliation: CNR - National Research Council of Italy, IAMC - Institute for the Coastal Marine Environment, 90782 Oristano, Italy. Electronic address: andrea.cucco@cnr.it.
authors.forename: Andrea
authors.initials: A
authors.lastname: Cucco
authors.affiliation: CNR - National Research Council of Italy, ISMAR - Institute of Marine Sciences, Castello 2737/f, 30122 Venice, Italy; Marine Research and Technology Center, Klaipėda University, Klaipėda, Lithuania.
authors.forename: Georg
authors.initials: G
authors.lastname: Umgiesser
mesh_terms: D003198:Computer Simulation; D062070:Hydrology / Q000379:methods*; D007558:Italy; D008962:Models, Theoretical
keywords: Finite elements; Numerical model; Residence time; Transport time scales; Venice Lagoon