Barrier island geomorphology, hydrodynamic modelling, and historical shoreline changes: an example from South Uist and Benbecula, Scottish Outer Hebrides

Alastair G. Dawson; Cristina Gomez; William Ritchie; Crispian Batstone; Mark Lawless; John S. Rowan; Sue Dawson; Jason McIlveny; Richard Bates; David Muir

doi:10.2112/JCOASTRES-D-11-00184.1

Barrier island geomorphology, hydrodynamic modelling, and historical shoreline changes: an example from South Uist and Benbecula, Scottish Outer Hebrides

Alastair G. Dawson
, Cristina Gomez
, William Ritchie
, Crispian Batstone
, Mark Lawless
, John S. Rowan
, Sue Dawson
, Jason McIlveny
, Richard Bates
, David Muir

JBA Consulting
University of Dundee
University of the Highlands and Islands
University of St Andrews
Comhairle nan Eilean Siar

Research output: Contribution to journal › Article › peer-review

9 Citations (Scopus)

Abstract

A quantitative reconstruction is provided of the evolution of Gualan Island, a barrier island located between South Uist and Benbecula in the Scottish Outer Hebrides using historical maps, aerial photographs and LiDAR (Light Detection and Ranging) data. Geomorphological changes over the last ca. 200 years are described together with quantitative changes in the dimension of the barrier island as well as rates of shoreline retreat. A series of digital terrain models (DTMs) provided the boundary conditions for a 2-D ocean circulation tide-surge model simulating water level and wave conditions associated with a highly destructive storm that took place during January 2005. During this storm event, the central part of the barrier island was overtopped by waves. Validating the hydrodynamic model against eye-witness and field evidence obtained after the 2005 storm allowed simulation of a range of potential future breaching scenarios. Thus with the same storm conditions a large barrier breach 500 m wide would result in wave heights rising by 0.8-0.9 m on hitherto sheltered shorelines.

Original language	English
Pages (from-to)	1462-1476
Number of pages	15
Journal	Journal of Coastal Research
Volume	28
Issue number	6
Early online date	13 Apr 2012
DOIs	https://doi.org/10.2112/JCOASTRES-D-11-00184.1
Publication status	Published - 1 Nov 2012

Bibliographical note

Major contribution - presenting results of interdisciplinary work on coastal flooding in the Scottish Outer Hebrides. Interdisciplinary research collaboration leads to better understanding of links between inter-island causeway construction, climate change and barrier island evolution.

We are grateful to Alison Sandison for cartographic help and to Jennie Morrison for preparing the revised manuscript. The paper is a contribution to the Scottish Alliance for Geoscience, Environment and Society (SAGES) and to NPP Project CoastAdapt.

Keywords

Barrier island
Gualan Island
Scottish Outer Hebrides
geomorphological reconstruction
January 2005 storm in Atlantic Scotland
digital terrain modelling
hydrodynamic models

Access to Document

10.2112/JCOASTRES-D-11-00184.1Licence: Unspecified

Cite this

Dawson, A. G., Gomez, C., Ritchie, W., Batstone, C., Lawless, M., Rowan, J. S., Dawson, S., McIlveny, J., Bates, R., & Muir, D. (2012). Barrier island geomorphology, hydrodynamic modelling, and historical shoreline changes: an example from South Uist and Benbecula, Scottish Outer Hebrides. Journal of Coastal Research, 28(6), 1462-1476. https://doi.org/10.2112/JCOASTRES-D-11-00184.1

Dawson, AG, Gomez, C, Ritchie, W, Batstone, C, Lawless, M, Rowan, JS, Dawson, S, McIlveny, J, Bates, R & Muir, D 2012, 'Barrier island geomorphology, hydrodynamic modelling, and historical shoreline changes: an example from South Uist and Benbecula, Scottish Outer Hebrides', Journal of Coastal Research, vol. 28, no. 6, pp. 1462-1476. https://doi.org/10.2112/JCOASTRES-D-11-00184.1

@article{be41d4bab90f4fd1b30f3fb3ea9b3771,

title = "Barrier island geomorphology, hydrodynamic modelling, and historical shoreline changes: an example from South Uist and Benbecula, Scottish Outer Hebrides",

abstract = "A quantitative reconstruction is provided of the evolution of Gualan Island, a barrier island located between South Uist and Benbecula in the Scottish Outer Hebrides using historical maps, aerial photographs and LiDAR (Light Detection and Ranging) data. Geomorphological changes over the last ca. 200 years are described together with quantitative changes in the dimension of the barrier island as well as rates of shoreline retreat. A series of digital terrain models (DTMs) provided the boundary conditions for a 2-D ocean circulation tide-surge model simulating water level and wave conditions associated with a highly destructive storm that took place during January 2005. During this storm event, the central part of the barrier island was overtopped by waves. Validating the hydrodynamic model against eye-witness and field evidence obtained after the 2005 storm allowed simulation of a range of potential future breaching scenarios. Thus with the same storm conditions a large barrier breach 500 m wide would result in wave heights rising by 0.8-0.9 m on hitherto sheltered shorelines. ",

keywords = "Barrier island, Gualan Island, Scottish Outer Hebrides, geomorphological reconstruction, January 2005 storm in Atlantic Scotland, digital terrain modelling, hydrodynamic models",

author = "Dawson, \{Alastair G.\} and Cristina Gomez and William Ritchie and Crispian Batstone and Mark Lawless and Rowan, \{John S.\} and Sue Dawson and Jason McIlveny and Richard Bates and David Muir",

note = "Major contribution - presenting results of interdisciplinary work on coastal flooding in the Scottish Outer Hebrides. Interdisciplinary research collaboration leads to better understanding of links between inter-island causeway construction, climate change and barrier island evolution. We are grateful to Alison Sandison for cartographic help and to Jennie Morrison for preparing the revised manuscript. The paper is a contribution to the Scottish Alliance for Geoscience, Environment and Society (SAGES) and to NPP Project CoastAdapt.",

year = "2012",

month = nov,

day = "1",

doi = "10.2112/JCOASTRES-D-11-00184.1",

language = "English",

volume = "28",

pages = "1462--1476",

journal = "Journal of Coastal Research",

issn = "0749-0208",

publisher = "Coastal Education Research Foundation Inc.",

number = "6",

}

TY - JOUR

T1 - Barrier island geomorphology, hydrodynamic modelling, and historical shoreline changes

T2 - an example from South Uist and Benbecula, Scottish Outer Hebrides

AU - Dawson, Alastair G.

AU - Gomez, Cristina

AU - Ritchie, William

AU - Batstone, Crispian

AU - Lawless, Mark

AU - Rowan, John S.

AU - Dawson, Sue

AU - McIlveny, Jason

AU - Bates, Richard

AU - Muir, David

N1 - Major contribution - presenting results of interdisciplinary work on coastal flooding in the Scottish Outer Hebrides. Interdisciplinary research collaboration leads to better understanding of links between inter-island causeway construction, climate change and barrier island evolution. We are grateful to Alison Sandison for cartographic help and to Jennie Morrison for preparing the revised manuscript. The paper is a contribution to the Scottish Alliance for Geoscience, Environment and Society (SAGES) and to NPP Project CoastAdapt.

PY - 2012/11/1

Y1 - 2012/11/1

N2 - A quantitative reconstruction is provided of the evolution of Gualan Island, a barrier island located between South Uist and Benbecula in the Scottish Outer Hebrides using historical maps, aerial photographs and LiDAR (Light Detection and Ranging) data. Geomorphological changes over the last ca. 200 years are described together with quantitative changes in the dimension of the barrier island as well as rates of shoreline retreat. A series of digital terrain models (DTMs) provided the boundary conditions for a 2-D ocean circulation tide-surge model simulating water level and wave conditions associated with a highly destructive storm that took place during January 2005. During this storm event, the central part of the barrier island was overtopped by waves. Validating the hydrodynamic model against eye-witness and field evidence obtained after the 2005 storm allowed simulation of a range of potential future breaching scenarios. Thus with the same storm conditions a large barrier breach 500 m wide would result in wave heights rising by 0.8-0.9 m on hitherto sheltered shorelines.

AB - A quantitative reconstruction is provided of the evolution of Gualan Island, a barrier island located between South Uist and Benbecula in the Scottish Outer Hebrides using historical maps, aerial photographs and LiDAR (Light Detection and Ranging) data. Geomorphological changes over the last ca. 200 years are described together with quantitative changes in the dimension of the barrier island as well as rates of shoreline retreat. A series of digital terrain models (DTMs) provided the boundary conditions for a 2-D ocean circulation tide-surge model simulating water level and wave conditions associated with a highly destructive storm that took place during January 2005. During this storm event, the central part of the barrier island was overtopped by waves. Validating the hydrodynamic model against eye-witness and field evidence obtained after the 2005 storm allowed simulation of a range of potential future breaching scenarios. Thus with the same storm conditions a large barrier breach 500 m wide would result in wave heights rising by 0.8-0.9 m on hitherto sheltered shorelines.

KW - Barrier island

KW - Gualan Island

KW - Scottish Outer Hebrides

KW - geomorphological reconstruction

KW - January 2005 storm in Atlantic Scotland

KW - digital terrain modelling

KW - hydrodynamic models

U2 - 10.2112/JCOASTRES-D-11-00184.1

DO - 10.2112/JCOASTRES-D-11-00184.1

M3 - Article

SN - 0749-0208

VL - 28

SP - 1462

EP - 1476

JO - Journal of Coastal Research

JF - Journal of Coastal Research

IS - 6

ER -

Barrier island geomorphology, hydrodynamic modelling, and historical shoreline changes: an example from South Uist and Benbecula, Scottish Outer Hebrides

Abstract

Bibliographical note

Keywords

Access to Document

Fingerprint

Cite this