Improving the Holocene glacier chronology of the Southern Alps/New Zealand enabling its reliable utilisation as palaeoclimatic archive

改进南阿尔卑斯山/新西兰的全新世冰川年代学，使其能够可靠地用作古气候档案

• 批准号: 439448631
• 负责人: Professor Dr. Stefan Winkler
• 金额: --
• 依托单位: Arbeitsbereich Physische Geographie
• 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/439448631?language=en
• 关键词: Improving; Holocene; glacier; chronology; Southern

Mountain glaciers are impressive indicators of present climate change and concurrently constitute high-resolution palaeoclimatic archives. Investigating Holocene glacier fluctuations provides valuable insights into their dominating climatic drivers, indispensable knowledge for any subsequent assessment of modern or prediction of future changes. Reliable interpretation of Holocene glacier archives and their correlation on global scale are essential for the understanding of global climate dynamics with their hemispheric and global interconnections. Apart from satisfactory spatial diversity this requires credible and representative regional data sets. Recent global compilations of Holocene glacier chronologies reveal, however, that only for very few mountain regions these requirements are fulfilled. Existing uncertainties prevent a sustainable utilisation of mountain glacier’s potential as palaeoclimatic archives. This constitutes a highly unsatisfactory situation.The Southern Alps of New Zealand’ are considered one of the rare key localities in the Southern Hemisphere for investigating Holocene glacier chronologies. Verified utilisation of their Holocene glacier chronology as palaeoclimatic archive fails, however, due to shortcomings in robustness and representativeness of work published to date. This has meanwhile been recognised beyond all doubt. Detailed reassessment revealed that several previously established glacier advances need to be dismissed, mainly due to major geomorphological uncertainties caused by strong regional morphodynamics. As a result, the Holocene glacier chronology of New Zealand should currently not be considered with palaeoclimatic interpretations on hemispheric or global scales. The existing uncertainties bear a substantial risk of subjective interference/bias and unjustified adjustment to preferred paradigms. Main aim of the proposed project is to establish a reliable Holocene glacier chronology applying Schmidt-hammer exposure-age dating (SHD) in combination with terrestrial cosmogenic nuclide dating (TCND). The selected approach particularly allows, in particular, to address and to tackle the specific regional uncertainties in line with an expansion of spatial diversity, major weakness of previous work. And unlike to chosen approach, terrestrial cosmogenic nuclide dating alone could not overcome these shortcomings. Intended outcome is a reliable and regionally representative Holocene glacier chronology for the Southern Alps, a result measuring up their potential as valuable climate archive. It should enable a palaeoclimatic analysis in combination with correlations to other glacier regions on regional, hemispheric, and global scales independent and unbiased by any predetermined paradigms.

山地冰川是当前气候变化的重要指标，同时也是高分辨率古气候档案的组成部分。对全新世冰川波动的研究提供了对其主要气候驱动因素的宝贵见解，是对现代或未来变化的任何后续评估或预测不可或缺的知识。全新世冰川档案的可靠解释及其在全球尺度上的相关性对于理解全球气候动力学及其半球和全球相互关系至关重要。除了令人满意的空间多样性外，这需要可信和具有代表性的区域数据集。然而，最近全球全新世冰川年表的汇编显示，只有极少数山区满足了这些要求。现有的不确定性阻碍了山地冰川作为古气候档案潜力的可持续利用。这是一种非常不令人满意的情况。新西兰的南阿尔卑斯山被认为是南半球研究全新世冰川年代学的罕见关键地点之一。然而，由于迄今为止发表的工作在稳健性和代表性方面的不足，他们的全新世冰川年表作为古气候档案的验证利用失败了。与此同时，这一点已得到了毫无疑问的承认。详细的重新评估表明，由于强烈的区域形态动力学导致的主要地貌不确定性，需要取消先前确定的一些冰川推进。因此，新西兰全新世冰川年代学目前不应考虑半球或全球尺度上的古气候解释。现有的不确定性存在很大的主观干扰/偏见和对首选范式的不合理调整的风险。该项目的主要目的是利用Schmidt-hammer暴露年龄测年（SHD）与陆地宇宙核素测年（TCND）相结合，建立可靠的全新世冰川年表。所选择的方法特别能够根据空间多样性的扩大来处理和处理具体的区域不确定性，这是以前工作的主要弱点。与选择的方法不同，单靠陆地宇宙核素测年无法克服这些缺点。预期的结果是一个可靠的和具有区域代表性的南阿尔卑斯山全新世冰川年表，结果衡量了它们作为有价值的气候档案的潜力。它应该能够使古气候分析与其他冰川区域在区域、半球和全球尺度上的相关性相结合，独立且不受任何预定范例的影响。