Collaborative Research: ANDRILL - - Investigating Antarctica's Role in Cenozoic Global Environmental Change

ANDRILL是一个科学钻探计划，旨在调查南极洲在过去6000万年来在全球气候变化中所扮演的角色。该方法综合了地球物理调查、新的钻探技术、多学科岩心分析和冰盖模型，以处理四个科学主题：(1)南极洲气候和冰盖的历史；(2)极地生物群和生态系统的演变；(3)主要构造和火山事件的时间和性质；(4)南极洲在地球海洋-气候系统中的作用。该合同启动了一个可能成为长期项目的项目，该项目将钻探麦克默多冰架下和麦克默多南部海湾两个以前无法接触到的沉积物记录。这些地层记录涵盖了南极洲主要冰盖形成的关键时期。麦克默多冰架网站的重点是罗斯冰架，其大小是全球气候变化的敏感指标。它最近经历了重大的冰川崩解事件，有证据表明，自上一次冰盛期以来，冰川收缩了1000公里。作为冷底水的发电机，大陆架也可能在海洋环流中发挥关键作用。从该地点获得的岩心还将深入了解冰架下的沉积、生物和海洋过程；罗斯岛火山活动的历史；以及岩石圈对火山载荷的挠曲响应，这对该地区的地球物理和构造研究非常重要。南麦克默多海峡遗址位于干燥山谷附近，重点关注东南极上方的主要冰盖。关于这片冰盖的稳定性，争论仍在继续。来自干燥山谷的证据支持相互矛盾的结论：至少在过去一千五百万年里是稳定的冰盖，还是最近几百万年前经历了膨胀和收缩的活动冰盖。限制这段历史对于深入研究全球气候变化模型至关重要。沉积物岩芯将被用来构建该地区整体的冰川和间冰期历史；包括记录海冰覆盖、海平面、陆地植被和融水排放事件。该核心还将为区域地震研究提供一个一般的年代地层框架，并有助于揭示该地区复杂的构造史。该项目的更广泛影响包括正式和非正式教育、新的研究基础设施、各种形式的合作，以及提高社会对全球气候变化的理解。支持博士后、研究生、本科生和K-12阶段的教育。教师和课程专家将被纳入研究计划，并将制作一系列视频资源，包括一部用于电视发行的科学纪录片。新的研究基础设施包括岩心分析和冰盖建模设备，以及开发一种独特的钻探系统来穿透冰架。钻探开发和整个项目得到了与科学家的国际合作以及新西兰、德国和意大利的国家南极计划的共同支持。该项目还在美国境内的研究机构和主要是本科生机构之间建立了新的合作。作为海平面上升、海洋和大气环流的关键因素，南极洲的冰盖对社会理解全球气候变化具有重要意义。ANDRILL提供了有关海洋和陆地温度的新数据，并改变了我们对极端气候事件的理解，如极地冰盖的形成。这些数据对于建立准确的地球气候未来模型至关重要。

ANDRILL is a scientific drilling program to investigate Antarctica's role in global climate change over the last sixty million years. The approach integrates geophysical surveys, new drilling technology, multidisciplinary core analysis, and ice sheet modeling to address four scientific themes: (1) the history of Antarctica's climate and ice sheets; (2) the evolution of polar biota and ecosystems; (3) the timing and nature of major tectonic and volcanic episodes; and (4) the role of Antarctica in the Earth's ocean-climate system. This award initiates what may become a long-term program with drilling of two previously inaccessible sediment records beneath the McMurdo Ice Shelf and in South McMurdo Sound. These stratigraphic records cover critical time periods in the development of Antarctica's major ice sheets. The McMurdo Ice Shelf site focuses on the Ross Ice Shelf, whose size is a sensitive indicator of global climate change. It has recently undergone major calving events, and there is evidence of a thousand-kilometer contraction since the last glacial maximum. As a generator of cold bottom water, the shelf may also play a key role in ocean circulation. The core obtained from this site will also offer insight into sub-ice shelf sedimentary, biologic, and oceanographic processes; the history of Ross Island volcanism; and the flexural response of the lithosphere to volcanic loading, which is important for geophysical and tectonic studies of the region.The South McMurdo Sound site is located adjacent to the Dry Valleys, and focuses on the major ice sheet overlying East Antarctica. A debate persists regarding the stability of this ice sheet. Evidence from the Dry Valleys supports contradictory conclusions; a stable ice sheet for at least the last fifteen million years or an active ice sheet that cycled through expansions and contractions as recently as a few millions of years ago. Constraining this history is critical to deep-time models of global climate change. The sediment cores will be used to construct an overall glacial and interglacial history for the region; including documentation of sea-ice coverage, sea level, terrestrial vegetation, and melt-water discharge events. The core will also provide a general chronostratigraphic framework for regional seismic studies and help unravel the area's complex tectonic history.The broader impacts of this project include formal and informal education, new research infrastructure, various forms of collaboration, and improving society's understanding of global climate change. Education is supported at the postdoctoral, graduate, undergraduate, and K-12 levels. Teachers and curriculum specialists are integrated into the research program, and a range of video resources will be produced, including a science documentary for television release. New research infrastructure includes equipment for core analysis and ice sheet modeling, as well as development of a unique drilling system to penetrate ice shelves. Drill development and the overall project are co-supported by international collaboration with scientists and the National Antarctic programs of New Zealand, Germany, and Italy. The program also forges new collaborations between research and primarily undergraduate institutions within the United States. As key factors in sea-level rise and oceanic and atmospheric circulation, Antarctica's ice sheets are important to society's understanding of global climate change. ANDRILL offers new data on marine and terrestrial temperatures, and changes our understanding of extreme climate events like the formation of polar ice caps. Such data are critical to developing accurate models of the Earth's climatic future.