Assessment of island beach erosion due to sea level rise: the case of the Aegean archipelago (Eastern Mediterranean)
The present contribution constitutes the first comprehensive attempt to (a) record the spatial characteristics of the beaches of the Aegean archipelago (Greece), a critical resource for both the local and national economy, and (b) provide a rapid assessment of the impacts of the long-term and episod...
| Main Authors: | , , , , , , , , , , , |
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| Format: | Article |
| Language: | English |
| Published: |
Copernicus Publications
2017-03-01
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| Series: | Natural Hazards and Earth System Sciences |
| Online Access: | http://www.nat-hazards-earth-syst-sci.net/17/449/2017/nhess-17-449-2017.pdf |
| Summary: | The present contribution constitutes the first
comprehensive attempt to (a) record the spatial characteristics of the
beaches of the Aegean archipelago (Greece), a critical resource for both the
local and national economy, and (b) provide a rapid assessment of the
impacts of the long-term and episodic sea level rise (SLR) under different
scenarios. Spatial information and other attributes (e.g., presence of
coastal protection works and backshore development) of the beaches of the 58
largest islands of the archipelago were obtained on the basis of
remote-sensed images available on the web. Ranges of SLR-induced beach
retreats under different morphological, sedimentological and hydrodynamic
forcing, and SLR scenarios were estimated using suitable ensembles of
cross-shore (1-D) morphodynamic models. These ranges, combined with
empirically derived estimations of wave run-up induced flooding, were then
compared with the recorded maximum beach widths to provide ranges of
retreat/erosion and flooding at the archipelago scale. The spatial
information shows that the Aegean <q>pocket</q> beaches may be particularly
vulnerable to mean sea level rise (MSLR) and episodic SLRs due to (i) their narrow widths
(about 59 % of the beaches have maximum widths < 20 m), (ii) their limited terrestrial sediment supply, (iii) the substantial coastal
development and (iv) the limited existing coastal protection. Modeling
results indeed project severe impacts under mean and episodic SLRs, which by
2100 could be devastating. For example, under MSLR of 0.5 m – representative concentration pathway (RCP)
4.5 of the Fifth Assessment Report (AR5) of the Intergovernmental Panel on
Climate change (IPCC)
– a storm-induced sea level rise of 0.6 m is projected to result in a complete
erosion of between 31 and 88 % of all beaches (29–87 % of beaches
are currently fronting coastal infrastructure and assets), at least temporarily.
Our results suggest a very considerable risk which will require significant
effort, financial resources and policies/regulation in order to
protect/maintain the critical economic resource of the Aegean archipelago. |
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| ISSN: | 1561-8633 1684-9981 |