The objectives of this project are:
- To narrow the gap between the behaviour-oriented models and the process-based models.
- To explore and extend the applicability of ASMITA and ESTMORF.
- To develop guidelines for determining the model parameters of ASMITA / ESTMORF.
The ultimate objective is to increase the suitability of the semi-empirical long-term morphological models for estuaries and tidal lagoons, developed by WL / Delft Hydraulics, as a tool in the consultancy practise.
To achieve these objectives, the following activities were carried out in 2004:
1. By participating in the DEFRA-project EstSim (fundamental research project financed by UK government to create semi-empirical models for LT estuarine morphological development), research was conducted on long-term morphological modelling of the Humber Estuary in co-operation with UK institutes. From this research we learned that the nodal tide variation is very important for the morphological changes in this estuary. Because of the relatively small morphological time scale of this estuary (morphologically very active), a clear signal of the 18.6 year cycle may be detected in the data of morphological changes. The ESTMORF model appears to be able to reproduce the response of the estuary to the nodal tide variation. Even more interesting is that the semi-empirical models (ESTMORF & ASMITA) indicate a non-linear interaction between the response to the sea-level rise and that of the nodal tide variation. Due to the nodal tide variation, the estuary appears to adjust to an accelerated sea-level rise much more rapidly.
2. In an MSc-project (Davor Maas), the Venice Lagoon was modelled using ASMITA (Maas, 2004) at the Technical University Delft in cooperation with Padua University, Italy. Furthermore, a MSc thesis (of Mr. Nortier) was completed in early 2004. For the Venice Lagoon case it appears to be important to include the salt marshes as an additional morphological element in the model schematisation. Furthermore, the schematisation outside the inlet requires adjustment due to the specific situation.
3. Publications. Participated to the PECS conference and a presentation was given on the prediction of the dredging requirement in the Western Scheldt Estuary based on ASMITAconcept.
4. Participating in the discussion on the effects of gas-mining in de Wadden Sea. The ASMITA model concept has been used as basis for the determination of the limit of land subsidence in combination with sea-level rise. |
