Meso-scale modelling of aeolian sediment input to coastal dunes

Delgado-Fernandez, Irene (2011) Meso-scale modelling of aeolian sediment input to coastal dunes. Geomorphology, 130 (3-4). pp. 230-243. ISSN 0169-555X DOI https://doi.org/10.1016/j.geomorph.2011.04.001

This is the latest version of this item.

[img]
Preview
PDF
DF_2011_GEOMORPHOLOGY_MODELLING_MESO-SCALE.pdf - Accepted Version
Available under License Creative Commons Attribution Non-commercial No Derivatives.

Download (968kB) | Preview

Abstract

The collection of a time series coupling hourly wind data (speed and direction) with sand transport over months has provided new insights into the dynamics of transport events that input sediment to the foredune at Greenwich Dunes, Prince Edward Island National Park, Canada. This paper summarises the key aspects of aeolian sedimentmovement for a period of 9 months and presents a modelling approach for resolving aeolian transport to coastal dunes at the meso-scale. The main hypothesis of the modelling approach is that a small number of key factors control both the occurrence and the magnitude of transport events. Thresholds associated with these factors may be used to filter the time series and isolate potential transport periods over the year. The impacts of nearshore processes are included in the approach as part of the dynamics of coastal dunes, as are supply-limiting factors and trade-offs between fetch distances, angle of wind approach, and beach dimensions. A simple analytical procedure, based on previously published equations, is carried out to assess the general viability of the conceptual approach. Results show that the incorporation of moisture and fetch effects in the calculation of transport for isolated potential transport periods result in improved predictions of sediment input to the dune. Net changes, measured with three different techniques, suggest that survey data with coarse temporal resolution underestimates the amount of sand input to the dune, because sediment is often removed from the embryo dune and foredune by other processes such as wave scarping. Predictions obtained by the proposed modelling approach are of the same order of magnitude as measured deposition and much less than predicted by models based solely on wind speed and direction. Areas for improvement and alternative modelling approaches, such as probabilistic approaches similar to weather forecasting, are covered in the discussion.

Item Type: Article
Subjects: G Geography. Anthropology. Recreation > GB Physical geography
G Geography. Anthropology. Recreation > GC Oceanography
G Geography. Anthropology. Recreation > GE Environmental Sciences
Divisions: Geography, Earth and Environmental Sciences
Date Deposited: 22 Apr 2016 11:59
URI: http://repository.edgehill.ac.uk/id/eprint/7584

Available Versions of this Item

Archive staff only

Item control page Item control page