A new multi-parameter toolkit to interrogate the source and climate impact of past volcanism

火山爆发向大气中喷射出大量的火山灰和气体。每年大约有5-10次大型火山事件，大约有6亿人（占世界人口的10%）居住在火山爆发时直接受到影响的附近。这些火山爆发可能导致重大的人类死亡，也可能对环境造成毁灭性的影响，火山灰和酸性沉降物覆盖了整个景观，破坏了庄稼，伤害了牲畜。尽管我们大多数英国人永远不会近距离目睹这些火山爆发，但它们仍然会对我们的生活产生影响。2010年4月和5月冰岛Eyjafjallajökull火山的喷发就证明了这一点。虽然这次喷发规模相对较小，没有造成任何人死亡，但它扰乱了数百万人的出行，给全球经济造成了数十亿英镑的损失。这一紧急情况凸显了我们现代全球化世界的脆弱性，以及英国不断受到火山事件破坏威胁的事实。火山学的主要目标之一是研究过去的火山事件，这样我们就可以了解它们的回归期和对环境的影响，并帮助社会为下一次“大”做好准备。令人惊讶的是，大爆发产生的火山产物具有区域性和全球性的分布，并且可以从喷发源传播数千公里。尽管在大多数地表环境中，这些沉降物很快被冲走并丢失。冰原是对这一问题的考察，钻入冰层并进入冰芯提供了过去火山爆发的无可争议的最佳记录。不幸的是，阅读这些过去火山活动的记录并不简单，尽管我们可以很容易地识别出这些古代火山喷发所沉积的富含硫的岩层和火山灰，但科学家们一直在努力了解火山源可能位于何处，或者它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次最大火山爆发中的7次的位置。如果我们能学会如何从这些冰芯记录中获得更多关于可能的来源和环境影响的信息，这将是一个重大突破——不仅能够帮助科学家在全球容易发生大型火山事件的地区进行火山监测，而且通过了解这些过去事件的频率和影响，我们可以减少经济影响。我的项目将利用冰芯研究的最新分析突破。特别是，最近的分析表明，火山硫化学编码了关于火山柱在大气中达到的高度的关键信息，因此它的气候变化潜力。我还将分析一路飘到冰盖上的微小火山灰样本的化学成分（其中许多样本的直径比人的头发还小）。我将在几次著名的火山爆发中考察这些技术，在那里我们既知道火山爆发的来源，也知道它们对气候的影响。一旦校准，我将使用该技术来确定冰芯记录中未知喷发的来源，并通过将我的结果与其他数据集进行比较来评估它们对气候和社会的影响。这个项目将提供有关过去火山喷发的震级、频率和类型的关键信息。这将有助于改进对未来火山事件的预测。做好充分准备将有助于限制生命损失，减少经济损失。对于英国，我们将深入了解冰岛大型火山事件的爆发频率。为了全球社会，我们将帮助查明过去火山爆发的来源，并评估地球上改变气候的火山爆发的频率。

Explosive volcanic eruptions spew enormous quantities of ash and gas in to the atmosphere. There are about 5-10 major volcanic events every year, and roughly 600 million people (10 % of the world's population) live close enough to be directly affected when they erupt. These eruptions may cause lead to significant human fatalities, and can also have devastating environmental impacts, covering the landscape in ash and acidic fallout, which destroys crops and harms livestock.Although most of us in the UK will never witness one of these eruptions up close they can still have an impact on our lives. This was demonstrated by the eruption of Eyjafjallajökull volcano in Iceland in April and May 2010. Although the eruption was relatively minor and did not kill anyone, it disrupted the travel of millions of people and cost global economics billions of pounds. This emergency highlighted the vulnerability of our modern globalised world, and the fact that the UK is at constant threat from disruption by volcanic events. One of the key goals of volcanology is to study past volcanic events so that we can understand their return periods and environmental impacts, and help prepare society for the next 'big one'. Amazingly, the volcanic products from large explosive eruptions undergo regional and global distribution and can travel thousands of kilometres from their eruption source. Although in most surface environments this fallout is rapidly washed away and lost. Ice sheets are the expedition to this, and drilling into the ice and accessing core provides the undisputed best records of past volcanic eruptions. Unfortunately, reading this record of past volcanism is not straightforward, and although we can easily identify the sulphur-rich layers and ash deposited by these ancient eruptions, scientists have struggled to understand where the source volcano might be located or 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. If we could learn how to get more information about the likely source and environmental impacts out of these ice core records, it would represent a major breakthrough - not only would be able to help scientists target volcano monitoring in regions of the globe that are prone to large volcanic events, but by understanding the frequency and impacts of these past events we can reduce the economic impacts.My project will take advantage of recent analytical breakthroughs in ice core research. In particular, recent analyses suggest that volcanic sulphur chemistry encodes critical information about the height the volcanic plume reached in the atmosphere, and hence its climate changing potential. I'll also analyse the chemical composition of the tiny ash samples that get lofted all the way to the ice sheet (many of which are smaller in diameter than a human hair). I shall interrogate these techniques for several well-known volcanic eruptions, where we know both the source and their climate-impact. Once calibrated, I will use the technique to determine the source of unknown eruptions in the ice core record, and evaluate their climate and societal impact by comparing my results to other data sets. This project will provide critical information on the magnitude, frequency and style of past eruptions. This will lead to improved forecasts of future volcanic events. Being better prepared will help limit the loss of life and reduce the economic losses. For the UK, we'll gain a thorough understanding of the eruption frequency of large volcanic events in Iceland. For global society, we'll help pinpoint the source of past eruptions and evaluate the frequency of climate-changing eruptions on Earth.