Paper No. 5
Presentation Time: 9:00 AM
OFFSHORE WINDS AND COASTAL FOREDUNES: ZONATION PATTERNS OF AIRFLOW AND TRANSPORT (Invited Presentation)
JACKSON, Derek W.T., Centre for Coastal & Marine Research, University of Ulster, Cromore Road, Coleraine, BT52 1SA, United Kingdom, DELGADO-FERNANDEZ, Irene, Natural, Geographical & Applied Sciences, Edge Hill University, St Helens Road, Ormskirk, L39 4QP, England, BAAS, A.C.W., Department of Geography, Kings College London, Strand, London, WC2R 2LS, COOPER, J. Andrew G., Environmental Science, University of Ulster, Cromore Road, Coleraine, BT52 1SA, United Kingdom, LYNCH, K., Department of Geography, National University of Ireland (Galway), University Road, Galway, Ireland and BEYERS, Meiring, Klimaat Consulting & Innovation, 49 Winston Crescent, Guelph, ON N1E 2K1, Canada, d.jackson@ulster.ac.uk
The transfer of windblown sand between foredune systems and beaches represents a key component of sediment budget analysis along many soft sedimentary coastlines. Traditionally, onshore wind components in local wind regimes are examined whereas offshore wind events have been excluded from analysis.
Recent work has shown that if the topography of the foredune is appropriate then this offshore component can be steered or undergo flow reversal through leeside eddying to give onshore transport events at the back beach under offshore flow conditions. At particular distances from the foredune crest flow reattaches to the surface to continue its incident offshore direction. The location of this reattachment point has important implications for aeolian transport of sand on the back beach and foredune toe locations.
This study based at Magilligan, Northern Ireland, reports on recent field experiments investigating the zonation patterns of flow behaviour in the lee of the foredune-beach zone and how transport patterns vary as a result of different wind events. Airflow modelling using CFD supplements the field experiments and characterisation of this important coastal interface.
