Dust Logging at Dome C for Abrupt Climate Changes, Large Volcanic Eruptions and Bolide Impacts

Dome C 的灰尘记录以了解气候突变、大型火山喷发和火流星影响

• 批准号: 0739743
• 负责人: Ryan Bay
• 金额: $ 24.86万
• 依托单位: University of California-Berkeley
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2008
• 资助国家: 美国
• 起止时间: 2008-07-01 至 2012-06-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0739743&HistoricalAwards=false
• 关键词: Dust; Logging; Dome; Abrupt; Climate

Bay 0739743This award supports a project to make high-resolution logs of dust and ash in the Dome C borehole using an optical dust logger. Logging at 20-50 cm/sec, in a matter of hours, mm-scale depth resolution of dust concentration and volcanic ash layers over the entire 3270 m borehole back to ~800 ka can be provided. The logger probes an area of order m2 of the horizon compared to the ~0.02 m2 core, greatly suppressing depositional noise and making the technique immune to core damage or loss. The method achieves unprecedented resolution of climate variations for matching or comparing ice core records, can detect particulate layers from explosive fallout which are invisible or missing in the core, and often reveals subtle trend changes which can elude standard core analyses. With the highly resolved dust record, it is expected to find new synchronous age markers between East Antarctica, West Antarctica and Greenland. The data could be instrumental in unifying global climate records, or resolving mysteries such as the transition from 41-kyr glacial cycles to apparent 100-kyr cycles. The project will extend previous finding, which make the most convincing case to date for a causal relationship between explosive volcanic events and abrupt climate change on millennial timescales. A search will also be made for evidence that some of the worldwide explosive fallout events that have been identified may have resulted from impacts by comets or asteroids. The investigators will evaluate the reliability of terrestrial impact crater records and the possibility that Earth impacts are considerably more frequent than is generally appreciated. Better understanding of the factors which force abrupt climate changes, the recurrence rate and triggering mechanisms of large volcanic eruptions, and the frequency of Gt to Tt-energy bolide impacts are of vital interest for civilization. The work plan for 2008-11 comprises modifying and testing of existing hardware in year one; logging field work, most likely in year two; data analysis and publication of results in year three. Because the EPICA collaborators will provide a suitable logging winch onsite, the logistical needs of this project are modest and can be accommodated by Twin Otter from McMurdo. The proposal is in the spirit of the International Polar Year (IPY) by forging an international collaboration with potential societal benefit. The project will provide interdisciplinary training to students and postdoctoral fellows from the U.S. and other countries.

BAY 0739743这项奖项支持一个项目，旨在使用光学灰尘记录仪在圆顶C钻孔中制作高分辨率的灰尘日志。在整个3270 m的井眼中，以20-50 cm/sec的速度记录尘埃浓度和火山灰层的深度分辨率可以提供回到〜800 ka。与〜0.02 m2的核心相比，该记录器探测了地平线的M2阶区域，从而极大地抑制了沉积噪声，并使该技术免疫了核心损伤或损失。该方法可实现匹配或比较冰核记录的气候变化的前所未有的分辨率，可以从核心中发现颗粒层，而爆炸性后果是核心中无形或缺少的，并且经常揭示出可以忽略标准核心分析的微妙趋势变化。 有了高度解决的灰尘记录，预计将在南极洲东部，南极和格陵兰岛之间找到新的同步时代标记。这些数据可能有助于统一全球气候记录，或解决从41千摩尔冰川周期过渡到明显的100公斤周期的谜团。 该项目将延长以前的发现，这是迄今为止最令人信服的案例，即爆炸性火山事件与千禧年时间尺度的气候变化之间的因果关系。还将搜索证据表明，已经确定的一些全球爆炸性后果事件可能是彗星或小行星的影响造成的。研究人员将评估陆地撞击火山口记录的可靠性，并且地球影响的可能性要比普遍欣赏的可能性要高得多。更好地了解迫使气候变化的因素，大型火山喷发的复发率和触发机制，以及GT到TT-Energy Bolide的影响的频率对文明至关重要。 2008-11的工作计划包括对第一年的现有硬件的修改和测试；伐木现场工作，很可能在第二年；数据分析和第三年的结果发布。由于Epica合作者将提供合适的伐木绞车现场，因此该项目的后勤需求是适度的，可以由McMurdo的Twin Otter容纳。 该提案是在国际极地年（IPY）的精神上，通过与潜在的社会利益进行国际合作。该项目将为来自美国和其他国家的学生和博士后研究员提供跨学科的培训。