New estimates of ongoing sea level change and land movements caused by Glacial Isostatic Adjustment in the Mediterranean region

TL;DR

This study provides new estimates of sea level change and land movements in the Mediterranean caused by Glacial Isostatic Adjustment, using ensemble modeling to quantify uncertainties and improve interpretation of geodetic data.

Contribution

It introduces the first ensemble GIA modeling approach for the Mediterranean, enhancing the understanding of GIA's role in sea-level and crustal deformation estimates.

Findings

GIA significantly influences Mediterranean sea-level variations.

Ensemble modeling reduces uncertainties in GIA predictions.

Results improve interpretation of geodetic data in the region.

Abstract

Glacial Isostatic Adjustment (GIA) caused by the melting of past ice sheets is still a major cause of sea-level variations and 3-D crustal deformation in the Mediterranean region. However, since the contribution of GIA cannot be separated from those of oceanic or tectonic origin, its role can be only assessed by numerical modelling, solving the gravitationally self-consistent Sea Level Equation. Nonetheless, uncertainties about the melting history of the late-Pleistocene ice sheets and the rheological profile of the Earth's mantle affect the GIA predictions by an unknown amount. Estimating the GIA modelling uncertainties would be particularly important in the Mediterranean region, due to the amount of high quality geodetic data from space-borne and ground-based observations currently available, whose interpretation demands a suitable isostatic correction. Here we first review previous results about the effects of GIA in the Mediterranean Sea, enlightening the variability of all the fields affected by the persistent condition of isostatic disequilibrium. Then, for the first time in this region, we adopt an ensemble modelling approach to better constrain the present-day GIA contributions to sea-level rise and geodetic variations, and their uncertainty.