Sea-level rise trends in the Attico–Cycladic region (Aegean Sea) during the last 5000 years

Abstract

Sea-level change during the last 18,000 years is a combination of eustatic, isostatic and tectonic contributions. In an effort to minimize the tectonic contributions, our study of sea-level changes in the Aegean Sea within historical times is focused on the aseismic Attico–Cycladic geotectonic zone. On the basis of archaeological information and radiocarbon dating of coastal sedimentological formations, a sea-level curve for the Attico–Cycladic massif has been constructed for the past 5000 years and compared with existing curves. According to this curve, the rapid increase of sea level concluded prior to 5.5 ka and was followed by a slow steady rise at a rate of 0.9 mm/a up to its present stage. The latter is attributed primarily to the process of thermal expansion and secondarily to the residual melting of the glaciers and existing ice-caps. By extrapolation of the curve, the sea level at the end of the 20th century is predicted to be about 9 cm higher than the present level; this value is much lower than the prediction of the last IPCC report (49 cm). If higher SLR rates are realised in the next few decades, then the excess 40 cm of the IPCC prediction can be attributed to human-induced global climatic change.