Multi-decadal assessment of shoreline changes and future response along the Acheloos river delta, Greece

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Published: Apr 20, 2026
DOI: https://doi.org/10.12681/mms.43030
Keywords:
Delta evolution Shoreline change Coastal geomorphology DSAS
STELIOS PETRAKIS
Institute of Oceanography, Hellenic Centre for Marine Research, 46.7 km Athens-Sounio Ave., Anavyssos 19013, Greece & Faculty of Geology and Geoenvironment, School of Science, National and Kapodistrian University of Athens, University Campus, Zografou 15784, Greece
https://orcid.org/0000-0003-1824-1278
EMMANUEL VASSILAKIS
Faculty of Geology and Geoenvironment, School of Science, National and Kapodistrian University of Athens, University Campus, Zografou 15784, Greece
SERAFIM POULOS
Faculty of Geology and Geoenvironment, School of Science, National and Kapodistrian University of Athens, University Campus, Zografou 15784, Greece
VASILIOS KAPSIMALIS
Institute of Oceanography, Hellenic Centre for Marine Research, 46.7 km Athens-Sounio Ave., Anavyssos 19013, Greece
https://orcid.org/0000-0003-0815-7451
Abstract

The present study investigates alterations in the coastal area of the Acheloos deltaic complex (W. Greece) during the period 1945 – 2020 and the shoreline response to anticipated sea-level rise under various RCP scenarios. The authors used two methods of analysis: area measurement in non-linear sections of the coast, and longitudinal displacement of the coastline using DSAS. The future state of the coastal area analyzed by considering IPCC predictions, adjusted for local conditions. The results reveal severe erosion in the entire study area, reaching 250 m (~3.4 m/yr) in places, mostly due to the diversion of the main Acheloos River channel, whereas coastal protection works constructed in the 90s have partially mitigated the erosional rate. The IPCC predictions for 2100 show a continuous shrinking of the delta by 10% to 20% of the present area, while under the most extreme climate scenario, deltaic area loss could reach 60%. Regardless of the prevailing scenario, it was estimated that for each 0.1 m of sea-level rise, the average land loss at the deltaic area is approximately 2.8 km2.

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Author Biographies
EMMANUEL VASSILAKIS, Faculty of Geology and Geoenvironment, School of Science, National and Kapodistrian University of Athens, University Campus, Zografou 15784, Greece

Faculty of Geology and Geoenvironment

SERAFIM POULOS, Faculty of Geology and Geoenvironment, School of Science, National and Kapodistrian University of Athens, University Campus, Zografou 15784, Greece

Faculty of Geology and Geoenvironment

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