Terrestrial system response to North Atlantic climate oscillations during the last glacial cycle: high resolution loess-palaeosol sequences from Remagen-Schwalbenberg (Middle Rhine Valley, Germany) - TerraClime

我们对第四纪气候变率和强迫的认识主要来自海洋和冰芯记录。相比之下，陆地系统对气候变化随时间变化的响应仍然定义不清。然而，了解景观对气候变化的反应至关重要：不仅因为我们人类生活在陆地上并与陆地相互作用，还因为陆地与大气的相互作用与海洋和冰盖的相互作用不同。因此，我们必须研究陆地和大气系统之间的反馈和强迫的性质。TERRACLIME项目将研究末次冰期（LGC）期间陆地系统对北半球气候变化的响应，基于德国中莱茵河谷Remagen-Schwalbenberg地区新的黄土-古土壤序列（LPS）。在准备研究期间进行的试点核心REM 3A产生了中欧和西欧最厚和最完整的景观响应序列，涵盖了LGC的大部分地区。早期研究的剖面和岩心记录不如新岩心长和完整，而且它们缺乏使用现有最先进方法的高分辨率古气候重建，以及可靠的高分辨率时间框架。对Schwalbenberg地区进行系统的地球物理勘探，将为进一步确定关键岩心和若干筛选岩心奠定基础。TERRACLIME研究设计将基于连环原则理解黄土对气候的响应；不同（关键和筛选）岩心之间的差异将使我们能够解耦作用于沉积物的局部、区域和超区域过程，并在三维空间上阐明黄土沉积和形成的性质。TERRACLIME将结合现有的方法（沉积学、矿物学和环境磁学）和最近开发的替代方法（无机和稳定同位素地球化学以及生物标志物分析）。LPS岩心分析将提供过去气候条件、沉积和沉积后蚀变过程以及植被历史的数据。生成的地球化学数据将进一步用于研究沉积物源区随时间的可能变化。该项目的关键是高分辨率发光测年，为施瓦尔本贝格序列建立可靠和独立的年龄模型。基于配对石英OSL和多矿物pIR-IRSL测年的年龄模型将有助于将新的Schwalbenberg LPS与区域和全球古气候档案进行直接比较，以阐明LGC期间北大西洋气候振荡的陆地响应。来自不同档案的年龄模型之间的同步或滞后将进一步提高我们对LGC上北半球海洋、冰芯和陆地气候变化记录仪之间联系的理解。

Our understanding of climate variability and forcing during the Quaternary is largely derived from marine and ice core records. The response of terrestrial systems to climate change through time, by contrast, remains poorly defined. Nevertheless, understanding landscape response to climate variability is of critical importance: not only because we as people live on and interact with the land, but also because land interacts differently with the atmosphere than do the oceans and ice sheets. Consequently we must investigate the nature of feedbacks and forcings between terrestrial and atmospheric systems.The TERRACLIME project will investigate terrestrial system response to northern hemisphere climate change during the last glacial cycle (LGC), based on novel loess-palaeosol sequences (LPS) from Remagen-Schwalbenberg (Middle Rhine Valley, Germany). Pilot core REM 3A, conducted during preparatory studies, yields the thickest and most complete sequence of landscape response to palaeoclimate in Central and Western Europe, spanning much of the LGC. The records of profiles and cores from earlier studies were not as long and complete as the new core, and they lacked high resolution palaeoclimate reconstruction using state of the art methods now available, as well as reliable high resolution chronological frameworks.Systematic geophysical prospection of the Schwalbenberg area will be the base to identify the thickest deposits for a further key core and several screening cores. The TERRACLIME research design will yield an understanding of loess response to climate based on the catena principle; variabilities between different (key and screening) cores will enable us to decouple local, regional and supra-regional processes acting on the deposits and to elucidate the nature of loess deposition and formation in three dimensions.TERRACLIME will combine established methods (sedimentology, mineralogy and environmental magnetism) with recently developed proxy approaches (inorganic and stable isotope geochemistry, and biomarker analyses). LPS core analyses will provide data on past climatic conditions, sedimentation and post-sedimentary alteration processes, and vegetation history. Geochemical data generated will furthermore be used to investigate possible shifts in sediment source areas through time.Pivotal to the project is high resolution luminescence dating to establish a reliable and independent age model for the Schwalbenberg sequences. The resulting age model, based on paired quartz OSL and polymineral pIR-IRSL dating, will facilitate direct comparison of the new Schwalbenberg LPS with regional and global palaeoclimate archives to elucidate terrestrial response to North Atlantic climate oscillations during the LGC. Synchronicity or lags between the age models from the different archives will further improve our understanding of the links between marine, ice core and terrestrial recorders of climate change in the northern hemisphere over the LGC.