Climate Drivers and Ancient History in Greenland Ice

从极地冰盖收集的冰芯包含了过去环境条件、气候和气候驱动因素的详细记录。例如，可以在冰中探测到大规模火山喷发的时间、大小，有时甚至是位置。在过去，这种喷发通常与强烈降温和降水模式变化有关，这些时期扰乱了粮食生产，导致饥荒、人类迁徙、政治动荡和冲突。其中一次喷发导致了1816年的“无夏之年”，导致整个北半球出现严重的粮食短缺。同样，冰芯包含过去工业排放金属、酸和其他污染物的详细记录。例如，铅污染是过去开采和冶炼铅/银矿石的一个特别敏感的指标，而且由于许多古代硬币是由银制成的，北极铅污染可以作为过去白银生产和整体经济活动的替代指标或指标。事实上，用最新的分析仪器对格陵兰冰芯进行了高深度分辨率的分析，已经得出了古代、中世纪和现代经济的准确年代(在一到两年内)。与瘟疫和战争等已知历史事件相比，历史学家、经济学家和考古学家可以通过对外部冲击的反应来评估过去社会的韧性，例如瘟疫的到来或火山喷发造成的气候破坏。这项研究的目标是开发一系列元素和化学物种的准确年代、高分辨率的冰芯记录，以扩大和扩大最近发现的下列之间的因果联系：(1)古代社会；(2)火山作用和水文气候；(3)战争、瘟疫、社会动荡和经济活动。这些工作的基础是从格陵兰冰盖东北侧翼的图努地区收集和分析约440米的冰芯。沿冰芯地点上游的冰流线上游延伸40公里的穿冰雷达探测将有助于解释气溶胶和水的同位素记录，以及了解上游沉积过程的变化可能产生的任何影响。将使用沙漠研究所的连续流动分析系统对冰芯进行分析，以建立过去4000年来与火山作用、生物质燃烧、海盐、大陆尘埃和工业污染有关的30多种化学物质的准确日期记录。冰核的年代将使用火山限制的年度层计数，辅之以已知太阳质子事件的宇宙成因核素的测量。对冰芯记录的解释将由一个跨学科小组进行，成员包括环境和气候科学家、火山学家、历史学家和社会科学家。还将开发一门以实验室为基础的课程，培训历史学家、经济学家、考古学家和其他相关领域的研究人员进行冰芯分析，以及如何利用冰芯记录来解决历史研究问题。该奖项反映了NSF的法定使命，并通过使用基金会的智力优势和更广泛的影响审查标准进行评估，被认为值得支持。

Ice cores collected from the polar ice sheets contain detailed records of past environmental conditions, climate, and climate drivers. For example, the timing, size, and sometimes even the locations of large volcanic eruptions can be detected in the ice. Such eruptions often were linked in the past to periods of strong cooling and changes in precipitation patterns that disrupted food production, leading to famines, human migrations, political unrest, and conflict. One such eruption led to the 'year without a summer' in 1816, which resulted in major food shortages across the Northern Hemisphere. Similarly, ice cores contain detailed records of past industrial emissions of metals, acids, and other pollutants. For example, lead pollution is an especially sensitive indicator of past mining and smelting of lead/silver ores, and because many ancient coinage was made of silver, Arctic lead pollution can be used as a proxy or indicator past silver production and so overall economic activity. Indeed, Greenland ice cores analyzed at high depth resolution with the latest analytical instruments have yielded precisely dated (within one to two years) proxies of ancient, medieval, and modern economies. When compared to known historical events such as plagues and wars, historians, economists, and archaeologists can assess the resilience of past societies through their response to external shocks such as the arrival of plagues or a climate disruptions resulting from volcanic eruptions. The goal of this research is to develop accurately dated, high-resolution, ice-core records of a broad range of elements and chemical species to expand and extend recently identified, causal linkages between (1) ancient societies; (2) volcanism and hydroclimate; and (3) wars, plagues, social unrest, and economic activity. Underpinning these efforts will be the collection and analysis of a ~440 m ice core from the Tunu region on the northeastern flank of the Greenland ice sheet. An ice-penetrating radar survey extending 40-km upstream along the ice-flow line upstream of the ice-core site will support interpretation of the aerosol and water isotope records, as well as understanding of any possible impacts from changes in deposition processes upstream. The ice core will be analyzed using the continuous flow analysis system at the Desert Research Institute to develop accurately-dated records of over 30 chemical species linked to volcanism, biomass burning, sea salts, continental dust, and industrial pollution during the past 4,000 years. The ice core will be dated using volcanically-constrained annual layer counting supplemented by measurements of cosmogenic nuclides from known solar proton events. Interpretation of the ice-core records will be conducted by an interdisciplinary team including environmental and climate scientists, volcanologists, historians, and social scientists. A laboratory-based course will also be developed to train historians, economists, archaeologists, and researchers from other related fields in ice-core analysis and how ice-core records can be used to address historical research questions.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.