The main objective of the SWITCH project is to characterize the fortnightly switching of residual flow drivers in a type of estuaries that has been largely unexplored. Two specific objectives will be addressed through the following questions:

  1. What is the along-estuary variability of the fortnightly switching in residual flow drivers?
  2. Does Fr0 provide a robust metric to diagnose the fortnightly switching at different locations along an estuary?

In order to address the objectives, we propose to combine measurements with numerical simulations at an estuary with semi-arid climate, the Guadiana.

As residual flows control salt intrusion in estuaries, the project studies a phenomenon of growing concern for many coastal populations, such as at the case study region due to the increasing occurrence of severe droughts. Thus, it also proposed to address management questions related to salinity intrusion following participatory approaches designed to optimize stakeholders’ involvement.

Milestones and Timetable
  • M1 – 01/07/2022, Control experiment: completion of the control experiment with simplified geometry (Task 1).
  • M2 – 01/12/2022, Workshop 1: First workshop with Stakeholders will have been performed, for the framing of relevant freshwater management issues at the Guadiana (Task 6).
  • M3 – 01/07/2023, Verification of Hypothesis 1: Characterization of the fortnightly switching of flow drivers along the estuary in function of the density field (Tasks 3 & 4).
  • M4 – 01/12/2023, Verification of Hypothesis 2: Representation of the spatial and temporal variability of Fr0 at the Guadiana estuary (Task 4).
  • M5 – 01/07/2024, Dynamic classification of the Guadiana: Placement of all results obtained at the Guadiana in non-dimensional dynamic space (Fr0 vs Ek diagram; Task 5).