The effects of Mediterranean sea surface temperature evolution on the Mediterranean sea-level reconstruction

In 2014, Rohling et al. presented a new method of reconstructing sea level which utilised a planktic foraminiferal oxygen isotope (δ18O) stack from the Mediterranean to create a sea-level record spanning the last 5.3 million years. Prior to this, all continuous, millennially resolved sea-level reconstructions beyond 500,000 years ago were based on deep-sea benthic δ18O foraminiferal data. Despite the different methods used for the deconvolution of benthic δ18O, these all relied on the same proxy, and therefore were not completely independent of each other.

The Mediterranean sea-level record enabled the first independent validation of the benthic δ18O-based sea-level records. The Mediterranean sea-level method assumed a linear relationship between sea surface temperature (SST) and global ice-volume, based on SST reconstructions for the last glacial cycle. However, a recent Mediterranean SST reconstruction spanning 3.5 - 1.5 Ma strongly suggests that Mediterranean SST did not have a constant linear response to ice volume through time. In this talk, I will present a preliminary exploration of the effects a long-term evolution in Mediterranean SST may have on the Mediterranean sea-level reconstruction. The recalculated Mediterranean sea-level record will then be compared with the original, and other existing sea-level reconstructions.