Sediment input to foredunes: description and frequency of transport events at Greenwich Dunes, PEI, Canada

Aeolian sediment transport from the beach to the foredune system can be predicted for periods of months or years from hourly wind data collected at standard meteorological stations. However, there is no corresponding data set of transport-limiting factors such as beach surface moisture, snow and ice, pebble lag and restricted fetch length. The remote sensing station described here has been specifically designed to acquire information on the dynamics of the beach and foredune system at high spatial and temporal resolution during long periods of time. The system consists of three digital SLR cameras covering different areas of interest of the beach and foredune controlled by a timer that takes pictures every hour. Coupled with measurements from a 2D Windsonic anemometer, saltation probes and Erosion/Deposition pins, the station provides extensive time series on those factors affecting aeolian transport. This information is managed by a geodatabase which can be used to query and identify the nature and frequency of events that deliver sand from the beach to the dunes. The first step is to obtain an estimate of when and how do transport events take place. For this purpose, a filtering technique has been designed to isolate periods of aeolian activity at the beach and reduce the volume of data to process. This paper presents preliminary results of behavior of the aeolian system at Greenwich Dunes, Prince Edward Island, Canada through a complete year of measurements, and introduces key aspects for future modeling and analysis.