Integrated Marine Biogeochemical Modelling Network to Support UK Earth System Research

生物地球化学是研究化学元素的循环，如碳和氮，这些元素要么是由生物活性驱动的，要么是对生物活性有影响的。海洋的生物地球化学在地球系统中发挥着重要作用：它调节主要化学元素的循环，并控制陆地、海洋和大气之间的相关反馈过程。海洋目前占据了人类活动排放的二氧化碳的约25%，将其储存在深水中数百年。这种吸收是在活跃的自然碳循环的背景下发生的，在这个循环中，碳在表层和深海之间不断地再循环，以响应物理、化学和生物过程。因此，海洋生物的变化可能会影响海洋对二氧化碳的吸收，并可能对气候产生重要影响。虽然对影响海洋生物地球化学循环的物理和化学过程(如循环、溶解度)已有较好的了解，但我们对生物过程的作用的了解还远远不够深入。这在很大程度上源于生物体内元素循环的复杂性，以及海洋群落的高度多样性(分类和功能)。目前，海洋生态系统受到人为环境变化的影响，特别是通过气候引起的物理性质的变化(例如洋流和温度)和海洋酸化(例如二氧化碳引起的pH下降)。如果我们要在本世纪及以后维持一个安全的环境，就必须提高我们对海洋生物地球化学的了解，以便我们能够更好地预测和量化其对全球变化的反应，从而我们能够更好地确定海洋与地球系统其他部分之间的潜在反馈。通过将经验知识合成到定量描述中，计算机模型使科学家能够调查生物地球化学和气候的功能及其相互作用。地球系统模型现在例行地模拟生物圈、大气、海洋、陆地表面和冰冻圈的生物地球化学相互作用，以研究气候系统的动力学并对未来气候进行预测。NERC和英国大都会博物馆的共同目标。该办公室将开发一种新的地球系统模型，能够预测从几天到几十年的环境变化对全球和区域的影响。这将包括一种新的、统一的海洋生物地球化学生物模拟方法。在数值模式中适当地表示与气候有关的海洋生物地球化学过程所需的细节是许多正在进行的辩论的主题。这导致了各种模型的不同，这些模型不仅在结构上不同，而且在关键生物过程的表述和参数化方面也不同。I-MarNet将评估英国现有的一套海洋生物地球化学模型，以便为下一个英国地球系统模型的决策提供信息。将对最近的过去和未来的100年进行模拟，以评估模型再现观测结果的能力，并量化模型的变化和对气候变化的反应。这一模型比较将提供新的信息，有助于确定生态系统复杂性在生物活动和海洋二氧化碳汇中的作用，以及生态系统复杂性对气候变化的敏感性。I-MarNet还将通过英国科学界的协调，制定一项战略计划，以最好的现有科学和现有模型的力量为基础，开发一种新的最先进的海洋生物地球化学模型。总而言之，该项目将提供重要的信息来指导英国的海洋生物地球化学模型的发展，并将确定一个路线图，以帮助解决关键的科学问题，并提供对气候系统功能的更好理解，以改善气候预测

Biogeochemistry is the study of the cycles of chemical elements, such as carbon and nitrogen, which are either driven by or have an impact on biological activity. The biogeochemistry of the oceans plays an important role in the Earth System: it regulates the cycles of major chemical elements and controls the associated feedback processes between the land, ocean and atmosphere. The oceans currently take up about 25% of the carbon dioxide emitted by human activities, storing it in deep waters for centuries. This uptake occurs against the backdrop of an active natural carbon cycle, where carbon is constantly recirculated between the surface and deep ocean in response to physical, chemical and biological processes. As a result, changes to ocean biology can influence the uptake of carbon dioxide by the oceans, and can have important implications for climate. While the physical and chemical processes that affect ocean biogeochemical cycles are relatively well understood (e.g. circulation, solubility), our understanding of the role of biological processes is far less advanced. In large part this stems from the complexity of elemental cycling within living organisms, and the high diversity (taxonomic and functional) of marine communities. At present, marine ecosystems are affected by anthropogenic environmental change particularly through climate-induced changes in physical properties (e.g. ocean currents and temperature) and by ocean acidification (e.g. carbon dioxide-mediated drop in pH). If we are to maintain a safe environment in this century and beyond it is essential that we improve our understanding of ocean biogeochemistry so that we can better forecast and quantify its response to global change, and so that we can better identify potential feedbacks between the ocean and the rest of the Earth System. By synthesising empirical knowledge into quantitative descriptions, computer models allow scientists to investigate the functioning of, and interactions between, biogeochemistry and climate. Earth Systems models now routinely simulate the biogeochemical interactions of the biosphere, atmosphere, oceans, land surface, and cryosphere in order to study the dynamics of the climate system and to make projections of future climate. A joint goal of NERC and the UK Met. Office is to develop a new earth system model capable of predicting global and regional impacts of environmental change from days to decades. This will include a novel and unified biological modelling approach for ocean biogeochemistry. The detail required to adequately represent the ocean biogeochemical processes relevant to climate in a numerical model is a subject of much ongoing debate. This has led to a diversity of models which differ not only in their structure, but also in their formulation and parameterisation of key biological processes. i-MarNet will evaluate the existing suite of ocean biogeochemical models in the UK in order to inform the decision for the next UK earth system model. Simulations of both the recent past and the next 100 years will be made to assess the ability of models to reproduce observations and to quantify the change and responsiveness of the models to climate change. This model comparison will provide new information that helps to identify the role of ecosystem complexity in the representation of biological activity and the ocean carbon dioxide sink, as well as the of both sensitivity to climate change. i-MarNet will also generate a strategic plan, via coordination of the UK science community, to develop a new state of the art ocean biogeochemical model that builds on the best available science and the strength of existing models. In summary, the project will provide crucial information to guide ocean biogeochemical model developments in the UK, and will define a roadmap to help resolve key scientific questions as well as provide a better understanding of the functioning of the climate system that improves climate projections