Microfluorination for Oxygen isotopes in Biogenic Silica (MOBiS)

人类活动引起的气候变化改变了世界各地的自然环境和人类系统，其广泛和日益严重的影响超出了自然气候变化的范围。为了更好地了解环境变化的驱动因素及其对生态系统和地球过程（例如水和碳的运动和储存）的影响，我们可以使用自然档案（例如海洋和湖泊沉积物记录），其中包含与过去气候变化有关的特定元素（同位素）的化学变化。过去自然环境对气候变化的响应可以为研究未来在不同的全球变暖情景下同样的环境可能如何变化提供重要信息。例如，考察极地地区，那里的冰盖融化对加速全球海平面上升有重大贡献。调查极地冰融化对过去地质时期气候变化的反应，包括在气候比今天温暖的时期，提供了重要信息，以确定对冰融化的主要控制，并确定未来事件对全球变暖的反应的可能性。关于过去环境变化的信息也可用于评估在重大人类影响之前生态系统的状况和过去几千年中发生的自然变异水平，环境如何因人类活动而发生变化，我们如何监测和恢复当今的生态系统，并防止未来人类活动的影响。特定化学元素的特定数量天然物质的组成（同位素）是由当时的环境条件决定的，这些信息在它们生长时被锁定在它们的结构中。例如，生活在海洋中的微生物的外壳和骨骼记录了它们在水中形成的氧同位素的比例。随着时间的推移（数百年至数百万年），气候变化导致海洋沃茨中氧同位素组成的变化，这些变化反过来又保存在海底沉积物中下沉和积累的生物遗骸中。这些遗骸一层一层地堆积，保存着水化学的变化，并按时间顺序排列;海底越深，沉积物就越古老。我们可以按顺序恢复这些沉积物，并通过记录研究骨骼遗骸中的同位素如何变化，从而重建过去的气候变化。从沉积物序列中可以分析的层越多，我们就可以获得关于过去气候变化的更多细节。在任何水体中生长并构建由玻璃（生物硅）制成的骨骼的微生物的氧同位素组成受主要环境条件的控制，并通常用于重建过去的气候。从这种材料中提取和测量氧同位素是一项高度专业化的技术，但需要大量样品，危险的化学品，并且时间和能源效率低下。沉积物档案的收集成本高、难度大，且所产生的样品资料有限。结合现有的提取方法，这限制了生物硅中氧同位素的可用信息量，无法回答有关过去气候变化的重要问题。为了解决这个问题，我们将购买一个新的系统，该系统将自动化，高温样品反应装置和高精度同位素测量仪器相结合，不需要使用危险化学品，提供更高的样品通量，并且需要显著减少的样本大小。新系统将使现有方法发生重大变化，使英国地质调查局能够处理来自每个沉积物序列的更多样本，并扩大可分析的环境样本范围，例如来自海洋、陆地和湖泊环境的生物二氧化硅浓度不高的样本。

Human-induced climate change has altered natural environments and human systems around the world, with widespread and increasingly severe impacts that are beyond natural climate variability. To develop a greater understanding of what drives environmental change and the influence it will have on ecosystems and Earth-processes (e.g. movement and storage of water and carbon), we can use natural archives (e.g. ocean and lake sediment records) that contain chemical variations of specific elements (isotopes) that relate to past climate change. The response of natural environments to climate change in the past can provide crucial information to investigate how the same environments might change in the future under different scenarios for global warming. For example, examining polar regions where melting ice caps contribute significantly to accelerating global sea level rise. Investigating polar ice melting in response to climate change in the geological past, including in periods that had a warmer climate than today, provides crucial information to identify the main controls on ice melting and determine the likelihood of future events in response to global warming. Information about past environmental change can also be used to assess the condition of an ecosystem before major human impact and the natural levels of variability that have occurred in past millennia, how the environment has changed due to human activity, how we can monitor and restore ecosystems today, and protect against future impacts from human activity.The particular amount of specific chemical elements (isotopes) that natural materials are made of is determined by prevailing environmental conditions and this information is locked in to their structure as they grow. For example, the shells and skeletons of microscopic organisms living in the ocean record the ratio of oxygen isotopes in the water which they formed in. Over time (hundreds to millions of years), changes in climate lead to variations in the oxygen isotope composition of ocean waters and these are in turn preserved in the remains of creatures that have sunk and built up in ocean floor sediments. Layer-by-layer these remains accumulate preserving changes the signature of water chemistry in a time-ordered sequence; the deeper under the ocean floor the older the sediment. We can recover this sediment in sequence and investigate how isotopes in the skeletal remains change through the record, which allows for past changes in climate to be reconstructed. The more layers that can be analysed from a sediment sequence, the more detail we can obtain about past climate change. The oxygen isotope composition of microscopic organisms that grow in any body of water and build skeletons made of glass (biogenic silica) is controlled by prevailing environmental conditions and is routinely used to reconstruct past climate. The extraction and measurement of oxygen isotopes from this material is a highly specialised technique, but requires large samples, dangerous chemicals, and is time and energy inefficient. Sediment archives are collected at great expense and difficultly, and produce limited sample material. Combined with the existing extraction method, this limits the amount of information available from oxygen isotopes in biogenic silica to answer important questions about past climate change.To tackle this issue, we will purchase a new system that combines an automated, high-temperature sample reaction device and high precision isotope measurement instrument that do not require the use of dangerous chemicals, provide substantially higher sample throughput, and require significantly reduced sample sizes. The new system will enable a step-change from the existing method allowing BGS to process many more samples from each sediment sequence and also expand the range of environmental samples that can be analysed, e.g. from ocean, land and lake settings, that do not have high concentrations of biogenic silica.