The lack of high quality, long-term field data has hampered the quantitative analysis of beach-dune systems, which has been partially overcome during the last decade by utilizing video imaginary to monitor long-term variations of rip currents, sand bars, or shoreline position. The use of remote sensing techniques in aeolian studies is at a very starting point though, and researchers are now realizing its potential for measuring fetch distances or moisture content at the beach. There are a number of issues associated with the different temporal/spatial scales of factors affecting the aeolian system, which are difficult to monitor during short-term experiments and which prevent numerical predictions of coastal dune evolution of being accurate over the medium scale. This paper reports on the application of remote sensing techniques to model aeolian processes in coastal areas, and its potential in establishing links between factors acting at different temporal scales. Digital SLR cameras have been installed at Greenwich Dunes in PEI National Park (Canada), each one taking hourly-continuous exposures of the beach and dune during daylight hours. A 2D sonic anemometer mounted at the top of the mast provides record of wind speed and direction. Sediment transport and deposition/erosion processes are measured using a set of Sabatech saltation probes and pins permanently deployed at the backshore area and at the base of the foredunes. The images are rectified into UTM coordinates and analysed following a set of post processing techniques with PCI Geomatica and ArcMap. The result is a large geodatabase with several layers of numerical information, such as detailed moisture maps or vegetation cover, and time series of wind characteristics and transport processes at the beach. This geodatabse is a primary source of information for modeling the aeolian system at Greenwich. The monitoring of the magnitude, frequency, and timing of events that deliver sediment to the dune will allow us to understand the relative importance of different key variables. The overall goal is to improve numerical predictions of aeolian input from the beach to the dune at mesoscale, and advance our knowledge in the key factors affecting foredune evolution to better assist management projects.
|Publication status||Published - 2008|
|Event||AQQUA Meeting - Baie Comeau, Quebec, Canada|
Duration: 19 Aug 2008 → 22 Aug 2008
|Period||19/08/08 → 22/08/08|