Multi-proxy reconstruction of climate variability during the last 250 ka using precisely dated speleothems from south-eastern Spain.

本研究的目的是利用洞穴主题重建过去250 ka西班牙东南部的陆地气候变率。西班牙东南部是欧洲南部最干旱的地区之一。根据政府间气候变化专门委员会的最新报告，目前干旱地区将遭受越来越频繁和持续时间越来越长的暖期和热浪，以及越来越严重和持续时间越来越长的干旱。这些变化伴随着环境和经济的巨大风险。因此，研究目前干旱地区的陆地古气候记录是非常重要的。由于干燥的气候条件，西班牙东南部的气候档案对降水的细微变化都非常敏感。然而，来自伊比利亚南部陆地气候档案的信息是有限的，而且主要限于花粉和沉积物序列，它们具有相对较低的时间分辨率，并且很难在放射性碳定年范围之外进行定年。年代较好的洞穴气候代用记录目前主要局限于西班牙北部，而该地区的特点是相对较高的湿度和温和的温度。我们将在西班牙东南部的Cueva Victoria以其壮观的更新世动物群而闻名，通过精确定年的流岩序列，以高时间分辨率重建过去的气候变化。我们将重点关注最后250 ka，它包含在几个岩心中。在这一时期，来自西班牙东南部的精确的、高分辨率的陆地记录还没有得到。初步数据表明，Cueva Victoria的流岩生长对过去的降水变化高度敏感，流岩生长阶段与过去的全球变暖阶段有关。230 / u法的精确测年将使我们能够确定西班牙东南部陆地海洋同位素阶段1、3、5和7的时间和持续时间，以及相应的子阶段。此外，我们将生成由相应生长阶段的高分辨率稳定同位素和微量元素剖面组成的多代理记录。这将使我们能够根据过去的气候变率对代理信号作出可靠的解释。在初步数据集中观测到的代理信号的高灵敏度强调了西班牙东南部最近约250 ka的独特古气候档案的巨大潜力。该材料的一部分已经成为申请人先前DFG提案的重点，但不幸被拒绝。审稿人的主要批评是前期工作不充分。不过，他们强调了该项目的总体潜力。根据他们的建设性意见，我建立了新的合作关系，并生成了额外的年龄和气候代理数据，以证明这些样本是一个非常有前途的古气候档案，可以准确地确定年代。

The objective of this proposal is the reconstruction of terrestrial climate variability in south-eastern Spain during the last 250 ka using speleothems. South-eastern Spain is one of the driest regions in southern Europe. According to the last IPCC report, currently arid regions will suffer from an increasing frequency and duration of warm spells and heat waves as well as increasing intensity and duration of droughts. These changes go along with substantial risks for both the environment and economy. Investigation of terrestrial paleoclimate records from currently arid areas is, thus, of great importance.Due to the dry conditions, climate archives from south-eastern Spain are highly sensitive to even subtle changes in precipitation. However, information from terrestrial climate archives in southern Iberia is limited and mostly restricted to pollen and sediment sequences, which have a relatively low temporal resolution and are difficult to date beyond the range of radiocarbon dating. Well-dated speleothem climate proxy records are currently mainly restricted to the northern part of Spain, which is, however, characterized by relatively high humidity and mild temperatures.We will reconstruct past climate variability at high temporal resolution from a precisely dated flowstone sequence at Cueva Victoria, south-eastern Spain, which is well known for its spectacular Pleistocene fauna. We will focus on the last 250 ka, which are contained in several drill cores. For this period, a precisely dated, high-resolution terrestrial record from south-eastern Spain is not available yet.Preliminary data show that flowstone growth at Cueva Victoria is highly sensitive to past changes in precipitation and that flowstone growth phases are related to past global warm phases. Precise dating by the 230Th/U-method will thus enable us to determine the timing and duration of Marine Isotope Stages 1, 3, 5 and 7 as well as the corresponding sub-stages in terrestrial south-eastern Spain. Furthermore, we will generate multi-proxy records consisting of high-resolution stable isotope and trace element profiles for the corresponding growth phases. This will enable a robust interpretation of the proxy signals in terms of past climate variability. The high sensitivity of the proxy signals observed in the preliminary data set emphasizes the large potential of this unique paleoclimate archive for the last ca. 250 ka in south-eastern Spain.Part of this material was already in the focus of a previous DFG proposal by the applicant, but was unfortunately rejected. The main criticism of the reviewers was that the preliminary work was insufficient. However, they highlighted the general potential of the project. Following their constructive comments, I established new collaborations and generated additional age and climate proxy data to proof that the samples are a very promising paleoclimate archive, which can be accurately dated.