Improvement of hydrodynamic models of shallow water bodies using combined Eulerian and Lagrangian observations

Intermittently Closed and Open Lakes or Lagoons (ICOLLs) are a subcategory of estuaries that exhibit limited exchange with the ocean and river flows. [1] This study focuses on improving hydrodynamic modelling in shallow water estuaries using GPS tracked Lagrangian drifter data. The inclusion of drifter data will improve hydrodynamic models, which are commonly used to assess and manage risks of flooding, sediment transport, and pollutants. Traditionally, Eulerian hydrodynamic models used in shallow water systems are calibrated using observations from fixed instruments. With the recent availability of inexpensive GPS tracked drifters that can be deployed in shallow estuaries [2], a higher density of data can be collected to improve the confidence in the hydrodynamic model outputs. The numerical model [3] is set up for an ICOLL in South East Queensland (Currimundi Lake).This model will be calibrated and validated using both Lagrangian and Eulerian data. The effectiveness of assimilated Lagrangian drifter data on improving the prediction of velocity and water heights in the ICOLL is investigated. The calibrated numerical model will further be used for modelling advection-dispersion of potential contamination, sediment transport, and flood modelling within the ICOLL.