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

在受干旱影响的地中海东部地区，更好地了解过去的水文气候变异性是提高我们估计这一气候敏感地区未来水平衡变化的能力的先决条件。古气候年代学，即在湖泊和海洋沉积物记录中识别过去火山喷发的火山灰(Tephra)，并将其用作时间平行标记，是实现这些古气候记录明确同步的理想方法。TEPH-ME项目的主要目的是通过Tephra时间标记将地中海东部地区的古环境记录联系起来，以确定区域上不同的水文气候对过去气候变化的反应。为实现这一目标，旨在首次在死海的ICDP沉积岩芯中，并因此从地中海东南部-莱万丁地区的一个关键的古气候档案中，识别出广泛存在的、年代准确的地中海密码短语。在死海沉积岩芯中确定地中海中部和东部火山岩省的这种冰盖，将使地中海冰盖地层框架进一步向东南延伸。此外，这将有助于改进目前国际地球科学中心死海古气候记录的年表，迄今为止，死海古气候记录的约束程度很低。将来自死海的古气候代理数据与迄今与该区域的Tephra框架相连的其他长期和高分辨率地中海气候记录同步，将有助于推断地中海东部对过去气候变化的自然水文气候反应，包括潜在的超前和滞后阶段关系和跷跷板模式。将特别关注最后一个间冰期(海洋同位素阶段--MIS5e)，包括从倒数第二次冰期(MIS6)到末次冰期早期(MIS5d-a)的终止。这一时间窗对古气候界具有重大意义，因为它是预测未来气候变化的可能类比。此外，重要的是要更好地了解南黎凡特的古水文变化及其作为早期现代人在上一次冰川-间冰期周期中离开非洲的迁徙走廊的意义。

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.