CryptoTEPHrochronology in the ICDP Dead Sea deep core as a key to synchronise past hydroclimate changes in the eastern MEditerranean (TEPH-ME)

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In the drought-affected eastern Mediterranean region, a better understanding of the past hydroclimate variability is a prerequisite to improve our capability to estimate future changes of the water balance in this climatically sensitive region. Tephrochronology, i.e. identifying volcanic ash (tephra) of past volcanic eruptions in lacustrine and marine sediment records and using them as time-parallel markers, is the ideal method to achieve unambiguous synchronization of these palaeoclimate records. The main aim of the TEPH-ME project is to link palaeoenvironmental records from the eastern Mediterranean region by tephra time-markers to determine the regionally different hydroclimatic responses to past climate change. To achieve this aim, widespread and well-dated Mediterranean cryptotephras are aimed to be identified, for the first time, in the deep ICDP sediment cores from the Dead Sea, and hence from a key palaeoclimate archive of the south-eastern Mediterranean-Levantine region. Identifying such tephras from central and eastern Mediterranean volcanic provinces in the sediment cores of the Dead Sea will allow extending the Mediterranean tephrostratigraphical framework further to the southeast. Moreover, this will enable improving the current chronology of the ICDP Dead Sea palaeoclimate record that is only poorly constrained so far. Synchronising palaeoclimate proxy-data from the Dead Sea with other long and high-resolution Mediterranean climate records that are, so far, connected to the tephra framework of this region, will allow inferring the natural hydroclimatic response to past climate changes across the eastern Mediterranean including potential lead- and lag-phase relationships and seesaw patterns. Particular focus will be set on the last interglacial period (marine isotope stage - MIS 5e), including its terminations from the penultimate glaciation (MIS 6), and to the early last glacial (MIS 5d-a). This time-window is of major interest to the palaeoclimate community, as it serves as possible analogue to the projected future climate change. Furthermore, it is important to better understand palaeohydrological changes in the southern Levant and its significance as migration corridor for early modern humans leaving Africa during the last glacial-interglacial cycle.