Caloca-Casado, Silvia (2018) Coastal vulnerability assessment of Co. Dublin and Co. Wicklow to impacts of sea-level rise. PhD thesis, National University of Ireland Maynooth.

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Abstract

This research identified the coastal areas of Counties Dublin and Wicklow most vulnerable to impacts of sea-level rise through the analysis of various indicators to provide an index-based assessment. Future vulnerability to potential impacts was also investigated. A primary challenge in understanding coastal exposure to water-level change was quantifying the important characteristics that make it susceptible to change over the next century. The bulk of the work comes from identification, compilation and quality control of indicators of coastal change, which in this area were found to be regional coastal slope, aspect, geomorphology, cliff type, mean tidal range, shoreline changes, mean significant wave height and relative sea-level rise. A case study to complement shoreline change evaluation was also carried out in south Co. Dublin using multi-temporal digital elevation models to assess volumetric changes on highly responsive, soft unconsolidated cliffs. High resolution 2D mapping was conducted from two CVI indexed-based maps using six and eight variables. The map showed levels of vulnerability from low to high assigned to different segments depending on their potential susceptibility to physical changes as water levels rise (exposure, sensitivity and adaptive capacity). The CVI showed that high vulnerability areas predominate in the southern areas from Arklow to Greystones. PCA analysis identified the main contributions as coming from cliff type and geomorphology, followed by wave and tidal range and lastly slope, and aspect, with minor contributions from shoreline change. Future sea level scenarios were derived from local, regional and global trends. A likely scenario showed estimates between 78 and 127cm. An upper limits projection of sea-level rise of 198cm for 2100 was derived for the worst case scenario. These estimates were used to asses the exposure of area to potential flooding when combining tide-surge water levels with local projected sea-level for 2040, 2060, 2080 and 2100. Maximum extreme water levels of 5.76m (0.5% AEP) and 5.67m and 5.58m OD Malin (1% and 2% AEP), were found by 2100. Two hotspots to the effects of future sea-level rise and storminess were identified in North Dublin (Bull Island and Sutton) and Wicklow from both current and future vulnerability assessments. A consistent methodology, within a well-defined conceptual framework and the development of a robust specific metric and accuracy of data, was crucial. Adapted methodologies used in this research provide a reference for future development of Irish coastal vulnerability maps nationwide. The work will enable policy makers and stakeholders to easily identify vulnerable areas and target investment for adaptation within realistic timeframes.

Item Type:	Thesis (PhD)
Keywords:	Coastal vulnerability assessment; Co. Dublin; Co. Wicklow; impacts; sea-level rise;
Academic Unit:	Faculty of Social Sciences > Geography
Item ID:	10245
Depositing User:	IR eTheses
Date Deposited:	28 Nov 2018 11:30
URI:
Use Licence:	This item is available under a Creative Commons Attribution Non Commercial Share Alike Licence (CC BY-NC-SA). Details of this licence are available here

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