Geodetic observation of geodynamic and glaciological processes at the Patagonian Ice Fields

巴塔哥尼亚冰原地球动力学和冰川过程的大地测量观测

• 批准号: 464551298
• 负责人: Dr.-Ing. Mirko Scheinert
• 金额: --
• 依托单位: Professur für Geodätische Erdsystemforschung
• 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/464551298?language=en
• 关键词: Geodetic; observation; geodynamic; glaciological; processes

Regionally in different ways, ice sheets, ice fields and glaciers are subject to mass changes in response to climate change, affecting valuable water resources, local hazards, global sea level and solid-earth processes. Today, the Northern and Southern Patagonian Ice Fields (NPI and SPI) undergo intense changes in extent, volume and mass. Yet, quantification and explanation of these changes remain uncertain. Ice-mass changes are interlinked with a substantial deformation of the underlying solid Earth. Uplift rates observed at the SPI are among the largest ice-induced rates worldwide. The exceptionally high magnitude of solid-earth deformation is related to the peculiar tectonic and rheological setting of the region, characterized by the subduction of a mid-oceanic ridge at the Chile Triple Junction, the opening of the Patagonian slab window and the upwelling of hot mantle material of very low viscosity. The modelling of load deformations in Patagonia – both of elastic deformation and glacial-isostatic adjustment (GIA) – faces the challenges of the peculiar rheological setting, of the uncertainty of recent ice-mass change and of the limited observational basis not only on Earth surface deformation.In order to improve this observational basis, this proposal aims to realise different measurement campaigns which will be closely coordinated in order to economise on costs. First, in close cooperation with a project lead by M. Braun (FAU Erlangen-Nürnberg) we will realize geophysical-glaciological flight campaigns of the Patagonian ice fields using the aircraft Polar-5/6 of Alfred Wegener Institute (AWI). Conducting these flight campaigns we will acquire airborne measurements of ice-surface height, of the internal layering of the ice bodies, and of the gravity field at the SPI and NPI. Second, it is aimed to carry out repeated geodetic GNSS measurements at existing markers both in Chilean and Argentinean Patagonia. As a result of these observation campaigns and the raw data processing we will obtain 3D coordinates of the flight trajectory, ice-surface elevation along the flight profiles, and gravity disturbances for both the SPI and NPI. For up to 35 sites in the region Puerto Natales – Torres del Paine (Chile) and east of the SPI (Provincia Santa Cruz, Argentina), respectively, we will obtain vertical and horizontal deformation rates.The temporal and financial efforts to realize the anticipated measurements are substantial. For both the flight campaigns and the GNSS field campaigns in southern Patagonia logistics are challenging considering complicated weather conditions, and especially for the ground-based works, long distances and difficult access to measurement sites. Thus, this proposal focusses solely on the acquisition of new data and the subsequent processing of the raw data. An integral analysis and interpretation of all acquired observables will be subject to a separate (subsequent) project.

在区域范围内，冰盖、冰原和冰川以不同的方式受到大规模变化的影响，以应对气候变化，影响宝贵的水资源、当地灾害、全球海平面和固体土过程。今天，巴塔哥尼亚北部和南部冰原（NPI和SPI）在范围、体积和质量上都发生了剧烈的变化。然而，这些变化的量化和解释仍然不确定。冰质量的变化与下面的固体地球的大量变形是相互联系的。在SPI观测到的抬升率是世界上最大的冰致抬升率之一。高强度的固体地球变形与该地区特殊的构造和流变环境有关，其特征是智利三重连接处洋中脊的俯冲，巴塔哥尼亚板块窗的打开以及低粘度热地幔物质的上涌。巴塔哥尼亚的载荷变形建模——弹性变形和冰川均衡调整（GIA）——面临着特殊的流变环境、近期冰质量变化的不确定性和有限的观测基础（不仅是地球表面变形）的挑战。为了改善这种观察基础，本提案旨在实现不同的测量活动，这些活动将密切协调，以节省成本。首先，与M. Braun （FAU erlangen - n<s:1> rnberg）领导的项目密切合作，我们将使用阿尔弗雷德·韦格纳研究所（AWI）的极地5/6号飞机实现巴塔哥尼亚冰原的地球物理-冰川学飞行活动。通过这些飞行活动，我们将获得冰表面高度、冰体内部分层以及SPI和NPI重力场的机载测量数据。其次，在智利和阿根廷巴塔哥尼亚的现有标记上进行重复的大地测量GNSS测量。作为这些观测活动和原始数据处理的结果，我们将获得飞行轨迹的3D坐标，沿飞行剖面的冰面高度，以及SPI和NPI的重力扰动。对于纳塔莱斯港-托雷斯德尔潘恩地区（智利）和SPI以东（阿根廷圣克鲁斯省）的多达35个地点，我们将分别获得垂直和水平变形率。为实现预期的测量所做的时间和财务努力是巨大的。考虑到复杂的天气条件，在巴塔哥尼亚南部的飞行活动和GNSS实地活动中，后勤工作都具有挑战性，特别是地面工作，距离远，难以进入测量地点。因此，本方案只关注新数据的获取和原始数据的后续处理。对所有获得的观测数据的整体分析和解释将在一个单独的（后续）项目中进行。