2D and 3D modelling of the Congo River and Region Of Freshwater Influence (ROFI) with SLIM
(2014) IMUM 2014 — Location: Lisbonne, Portugal (25.August.2014)
Files
Details
- Authors
- Abstract
- With the second largest river outflow in the world and one of the widest hydrological basins in the world, the Congo River is of major importance both locally and globally. However, relatively few studies have been conducted on its hydrology, as compared to other great rivers such as Amazon, Nile, Yangtze or Mississippi rivers. e Congo River estuary contains important natural resources, like oil and gas, whose extraction could benefit from ocean currents simulations. As it is also the location of several vulnerable ecosystems, such as the Mangroves National Park, these simulations can also be a useful tool to ensure these areas will not be impacted by the exploitation of the up-cited resources. To model this area, we are using the hydrodynamical model SLIM ( http://www.climate.be/slim/ ), a finite elements model using unstructured grid. ere are many challenges to accurately model such a complex area. ese include the river bathymetry that alternates very shallow (less than 5 m) and very deep (more than 500 m) areas. e river fan is the only river fan of this importance still active nowadays. ese constraints justify an approach combining 2D and 3D high-resolution modelling. Achieving this implied to take great care in creating a numerical code which is flexible and modular as well as efficient in term of computation time. While 2D unstructured mesh ocean models are now quite mature, unstructured-mesh 3D models are still in their infancy. Many challenges remain, such as finding a trade-off between solution accuracy, robustness and computation time, or σ -layer versus z-layer modelling. Moreover, the Congo river being located in a very remote region,datasets are sparse and setting boundary conditions or validating the model is thus particularly challenging. We have developed several tools to help us to deal with these data. In this talk, we will present the technical issues, either dealing with data or numerical issues, we had to tackle with to set both the 2D and the 3D models. Solutions are validated with respect to tidal gauges and satellite altimetry data. We also simulate the water age evolution under various hydrodynamical regimes. All these developments show the relevancy of this approach and open the way for modelling including more phenomenon.
- Affiliations
Citations
Le Bars, Y., Vallaeys, V., Deleersnijder, E., & Hanert, E. (2014). 2D and 3D modelling of the Congo River and Region Of Freshwater Influence (ROFI) with SLIM. IMUM 2014, Lisbonne, Portugal. https://hdl.handle.net/2078.5/230276