Context and objectives
The research hypothesis of the present project is that 3D turbidity profiles of the seawater column can be produced by combining two techniques, i.e. optical remote sensing and multibeam echo-sounding (MBES). Satellite-derived turbidity has already become a product in the portfolio of companies specialized in earth observation. On the other hand, MBES-derived turbidity is new and not yet applied in the field. Simmons et al. (2017) tested MBES in a controlled environment, demonstrating the capabilities of the device to detect suspended material.
We will evaluate methods to merge data from optical remote sensing with MBES to produce 3D turbidity profiles. We will investigate if the combination of different wavelengths of optical remote sensing is able to provide more information about the vertical distribution of turbidity at the upper layer of the water column. Differences in temporal and spatial resolution should be taken into account. A direct comparison between both techniques will be done in the expected overlapping depth zone in the water column. If successful, it is checked whether the information from one technique can be used to help improving the results based on the other technique.
The study site is the Belgian part of the North Sea, is a well-known dynamic and turbid area investigated already for decades. Furthermore, it is easily accessible from Ostend (home base of VLIZ).
MBES is one of the most used marine survey tools in the world. Consequently, this project has the future potential to help generating new datasets from vessels of opportunity to validate optical remote sensing end products and yield useful sediment budget data applicable in e.g. coastal engineering.
Expected scientific results
By combining information from different wavelengths, new insights might be obtained to deduce more information regarding the vertical distribution of turbidity at the upper layer of the water column based on high spatial resolution sensors like Sentinel-2.
Report and/or manuscript on the suitability of the multibeam echo-sounder as a tool to characterize the sediment charge in the water column over a 3D volume and comparison of the performance with classic point measurements like environmental buoy systems. A procedure is set up for the installation of the multibeam echo-sounder device on a vessel together with a proposed set of acquisition parameters.
List of expected precisions and accuracies of multibeam echo-sounding and optical remote sensing under specific in situ (weather) conditions.
Expected products and services
First prototype of an integration toolbox to couple multibeam echo-sounding and optical remote sensing in order to produce 3D turbidity profiles. This toolbox will take into account the different spatial resolutions and precisions of both techniques.
|Project leader(s):||Vlaams Instituut voor de Zee|