Quantitative climate reconstruction for MIS 3 in Central Europe based on multi-proxy data from precisely dated speleothems (flowstones) from Bleßberg Cave, Germany

基于来自德国布莱伯格洞穴精确年代的洞穴沉积物（流石）的多代理数据，对中欧 MIS 3 进行定量气候重建

• 批准号: 449287287
• 负责人: Professor Dr. Denis Scholz
• 金额: --
• 依托单位: Sektion 4.3: Klimadynamik und Landschaftsentwicklung
• 依托单位国家: 德国
• 项目类别: Research Grants
• 资助国家: 德国
• 项目状态: 未结题
• 来源: https://gepris.dfg.de/gepris/projekt/449287287?language=en
• 关键词: Quantitative; climate; reconstruction; MIS; Central

The last glacial period exhibited much larger climate variability than the Holocene. In particular, Marine Isotope Stage (MIS) 3 (ca. 57-27 ka) was characterised by rapid climate oscillations (the Greenland Interstadials), which show rapid warming followed by gradual cooling. The impact of these interstadials in Central Europe is not clear yet. In terrestrial northern western Europe (>50° N), fragmentary organic deposits intercalated in non-organic glacial deposits are interpreted as evidence for interstadials, and pollen analysis indicates open, treeless vegetation. In northern central Europe, interstadials are typically characterised by tundra vegetation with a variable component of shrubs and sparse boreal trees. Due to chronological uncertainties, precise assignment of the terrestrial European interstadials north of 50° N to particular Greenland Interstadials is not possible.Speleothems have great potential for climate reconstruction, in particular because they can be dated very precisely by the 230Th/U-method. North of 47° N, speleothem growth during MIS 3 in Europe has so far only been detected in three caves. For two of those, only 230Th/U-ages, but no climate proxy data have been reported. Thus, there is only a single MIS 3 speleothem proxy time series from Central Europe available, which is restricted to two growth phases from ~52 to ~51 and ~47 to ~43 ka. This suggests that climate was too cold and/or dry during large parts of MIS 3 to enable speleothem growth north of the Alps in Central Europe.Here we propose to study two speleothems from Bleßberg Cave, eastern Germany. These flowstones show several growth periods during MIS 3 that have not been detected yet in other speleothems from Central Europe. This provides the unique opportunity to obtain precisely dated palaeoclimate information for these intervals, which reflect the impact of Greenland interstadials in terrestrial Europe. This is of particular interest because Bleßberg Cave is located at ca. 50 °N, beyond the northern limit for temperate forest development during MIS 3 in Europe.We will generate a precisely dated multi-proxy climate record for MIS 3 and the Late Glacial including d13C and d18O values, trace elements, Sr isotopes as well as dD and d18O values in speleothem fluid inclusions. Furthermore, we will apply a unique and novel combination of cave monitoring, isotope-enabled climate modelling and modelling of processes occurring in the soil and karst above the cave to obtain a better understanding of the processes influencing the proxy signals at the cave site and to disentangle the factors influencing the speleothem d18O values. This should enable us to provide a quantitative reconstruction of climate variability during MIS 3, which will then be compared with Holocene proxy records from Bleßberg Cave as well as with other global and regional climate records to reconstruct spatial variability and potential tele-connections.

与全新世相比，最后一个冰川时期暴露了更大的攀岩变化。特别是，海洋同位素阶段（MIS）3（大约57-27 ka）的特征是快速攀爬振荡（格陵兰的星座），它们显示出快速变暖，然后是级别冷却。这些间座位在中欧的影响尚不清楚。在西欧陆地陆地（> 50°N）中，中欧北部插入的碎片有机沉积物通常以苔原蔬菜为特征，这些蔬菜具有可变的灌木和稀疏的蜂房树。由于按时间顺序不确定性，不可能将50°N以北的欧洲陆地内部岩体的精确分配到特定的格陵兰内部座谈会。Speleothems具有巨大的气候重建潜力，尤其是因为它们可以由230/U-Method进行非常精确的日期。在47°N以北，到目前为止，欧洲的MIS 3期间的脾增长仅在三个洞穴中被发现。对于其中两个，只有第230/U-AGE，但尚未报告气候代理数据。这就是来自中欧的单个MIS 3脾脏代理时间序列，仅限于〜52至〜51至〜47至〜43 ka的两个增长阶段。这表明在MIS 3的大部分地区，气候太冷和/或干燥，无法使中欧的阿尔卑斯山以北的Speleothem生长。在这里，我们建议研究来自德国东部Bleßberg洞穴的两个斑点。这些流石显示在MIS 3期间的几个增长时期，这些时期尚未在中欧的其他speleothems中被发现。这为这些间隔提供了精确的古气候信息的独特机会，这反映了格陵兰园区在欧洲陆地上的影响。这特别令人感兴趣，因为Bleßberg洞穴位于CA。 50°N，超出了欧洲MIS 3期间温度森林发展的北部限制。我们将产生MIS 3和晚期冰川的精确日期的多型气候记录，包括D13C和D18O值，Trace Elements，SR同位素以及Spelethempliothempliothempluid cymentions中的DD和D18O值。此外，我们将采用洞穴监测，支持同位素的气候建模和在洞穴上方发生的过程的过程的独特而新颖的组合，以更好地理解影响洞穴位点的代理信号的过程，并使影响Speleothem d18o值的因素不易于。这应该使我们能够在MIS 3期间提供攀登变异性的定量重建，然后将其与Bleßberg洞穴的全新世代理记录以及其他全球和区域气候记录进行比较，以重建空间可变性和潜在的电视连接。