Taking Earth's volcanic pulse: understanding global volcanic hazards by unlocking the ice core archive

掌握地球火山脉搏：通过解锁冰芯档案了解全球火山危害

• 批准号: MR/X024016/1
• 负责人: William Hutchison
• 金额: $ 75.77万
• 依托单位: University of St Andrews
• 依托单位国家: 英国
• 项目类别: Fellowship
• 财政年份: 2023
• 资助国家: 英国
• 起止时间: 2023 至 无数据
• 项目状态: 未结题
• 来源: https://gtr.ukri.org/projects?ref=MR%2FX024016%2F1
• 关键词: Taking; Earth; volcanic; pulse; understanding

At the start of 2022, a little studied Pacific Island volcano, Hunga Tonga-Hunga Ha apai, erupted with an energy ~1000x greater than the atomic bomb dropped on Hiroshima. This eruption created waves that reverberated around the Earth and sent up a volcanic plume that reached ~55 km, half-way to space. Although this eruption was devastating for Tonga, mercifully, from a global perspective, it was short in duration and did not occur in a densely populated area or one of vital food production, transport, or energy transmission. Had it done so there would have been major impacts on climate and society.Volcanologists study past volcanic events so that we can understand their return periods and impacts and help prepare society for the next 'big one'. Large eruptions loft enormous quantities of ash and gas into the atmosphere, these plumes undergo regional and global distribution and can travel thousands of kilometres from their source. In most surface environments the fine-grained volcanic fallout is rapidly washed away. Ice sheets are the exception to this, and by drilling into the ice and extracting core scientists can identify the sulfur-rich layers and ash deposited by these past eruptions. Although ice cores provide the undisputed best archive of past volcanism, interpreting this record is not straightforward and our current techniques tell us little about where the source volcano was located and what its climate impact might have been. Even in records that span the last 2500 years, we only know the location of 7 of the 25 largest volcanic eruptions.This project will develop novel ice core chemical analyses to extract detailed information on the source, style, and environmental impacts of past volcanism. It will take advantage of two recent breakthroughs in ice core research. The first is high time resolution chemical analysis of volcanic sulfur which provide critical information about the height the volcanic plume reached in the atmosphere and the proximity of the eruptive source to the ice sheet. The second is ash particle chemistry which can help pinpoint the volcanic source and setting. During the first phase of this fellowship, we validated these techniques for well-known eruptions where we already have good information on the eruptive source, style and climatic impacts. We set up new protocols to analyse tiny fragments of ash (many of which are smaller in diameter than a human hair) and developed a computer model that can predict the sulfur chemistry for different eruption styles, allowing us to infer the source and climate impact directly from the ice core fingerprint.In the final phase of this project, we will apply our new techniques to unravel the source and climate impacts of the greatest eruptions in the ice core archive. Many of these are mystery eruptions, where we know there was a massive sulfur emission, but we don't yet know the exact volcanic source. Understanding the source of these massive mystery eruptions is one of the outstanding challenges in volcanology and paleoclimate, and our techniques will undoubtedly provide fascinating insights into these exceptional events and stimulate new interactions between volcanologists, climatologists, and historians.This project will provide critical new information about volcanism on Earth. To ensure maximum impact we will embed these findings in global volcanic hazard databases which will be used by scientists, governments, and industry (e.g., aviation and insurance) to quantify the magnitude, frequency and style of past eruptions and improve forecasts of future volcanic events. Our work will provide fundamental insights the climate impacts of past eruptions and will also help scientists and policy makers to target volcano monitoring in regions of the globe that are prone to large volcanic events. Ultimately, with this knowledge we will be better prepared for the next 'big one' and this will help limit the loss of life and reduce the economic losses.

2022 年初，一座鲜为人知的太平洋岛屿火山——洪加汤加-洪加哈阿派火山喷发，其能量比投放在广岛的原子弹大约 1000 倍。这次喷发产生的波浪在地球周围回荡，并喷射出高达约 55 公里的火山羽流，到达太空的一半。尽管这次喷发对汤加来说是毁灭性的，但幸运的是，从全球角度来看，它持续的时间很短，并且没有发生在人口稠密的地区或重要的粮食生产、运输或能源传输地区。如果这样做的话，将对气候和社会产生重大影响。火山学家研究过去的火山事件，以便我们能够了解它们的重现期和影响，并帮助社会为下一次“大火山”做好准备。大规模喷发将大量火山灰和气体释放到大气中，这些羽流会经历区域和全球分布，并且可以从源头传播数千公里。在大多数地表环境中，细粒火山沉降物会迅速被冲走。冰盖是个例外，通过钻入冰层并提取核心，科学家们可以识别出过去火山喷发所沉积的富含硫的层和火山灰。尽管冰芯无可争议地提供了过去火山活动的最佳档案，但解释这一记录并不简单，而且我们目前的技术几乎无法告诉我们源火山的位置及其对气候的影响可能是什么。即使在过去 2500 年的记录中，我们也只知道 25 次最大火山喷发中的 7 次的位置。该项目将开发新型冰芯化学分析，以提取有关过去火山活动的来源、类型和环境影响的详细信息。它将利用冰芯研究最近的两项突破。第一个是火山硫的高时间分辨率化学分析，它提供了有关火山羽流在大气中达到的高度以及喷发源与冰盖的接近程度的关键信息。第二个是火山灰颗粒化学，可以帮助查明火山的来源和环境。在该项目的第一阶段，我们针对著名的火山喷发验证了这些技术，我们已经掌握了有关喷发源、类型和气候影响的详细信息。我们建立了新的协议来分析微小的火山灰碎片（其中许多直径比人的头发还小），并开发了一种计算机模型，可以预测不同喷发方式的硫化学成分，使我们能够直接推断来源和气候影响在该项目的最后阶段，我们将应用新技术来揭示冰芯档案中最大火山喷发的来源和气候影响。其中许多都是神秘的火山喷发，我们知道那里有大量的硫排放，但我们还不知道确切的火山来源。了解这些大规模神秘喷发的根源是火山学和古气候领域的突出挑战之一，我们的技术无疑将为这些特殊事件提供令人着迷的见解，并刺激火山学家、气候学家和历史学家之间的新互动。该项目将提供重要的新信息关于地球上的火山活动。为了确保产生最大的影响，我们将把这些发现嵌入全球火山灾害数据库中，科学家、政府和行业（例如航空和保险业）将使用该数据库来量化过去火山喷发的规模、频率和类型，并改进对未来火山事件的预测。我们的工作将为过去火山喷发的气候影响提供基本见解，还将帮助科学家和政策制定者针对全球易发生大型火山事件的地区进行火山监测。最终，有了这些知识，我们将为下一个“大事件”做好更好的准备，这将有助于限制生命损失并减少经济损失。