Fate of ocean oxygenation in a warming world

氧气对所有高等生物的健康至关重要。自1960年以来，海洋中的溶解氧浓度下降了2%，并且由于人为的气候变化，预计未来将继续下降。未来的脱氧，沿着过度捕捞，威胁到具有重要经济意义的渔业和海洋生态系统的可持续性，并将影响全球生物地球化学循环。因此，我们必须对未来的情况有一个充分的了解。目前预测未来的模型模拟具有相当大的不确定性;它们并不都同意，并且严重低估了过去50年的文件减少。这表明这些模型缺少关键的相互作用，需要采取紧急行动和专门的包容性科学方法。FARGO通过解决为什么以及在什么程度上海水溶解氧浓度可能在变暖的世界中发生变化来提供这种方法。FARGO将通过一个创新的专门研究方案，研究太平洋（目前海洋中最大的低氧水体）的溶解氧浓度，该方案将采用一种新颖的多代理方法，在关键的温暖时间间隔内为IPCC型气候模型模拟提供数据：（400 - 1500万年）;ii-温暖的气候作为未来的模拟（上新世中期温暖期，330万年至300万年前）;iii-更新世温暖期（最后一个世纪的间冰期）。80万年）。FARGO分为两个阶段：第一阶段（1-4年）和第二阶段（5-7年）。前四年的重点是分析，以推进方法开发和重建氧浓度的时间序列和驱动变化的相关过程（海水变暖，分层，生产力，通风）。FARGO将用于创建这些时间序列的材料涉及称为有孔虫的微生物外壳。一些物种漂浮在海洋表面附近，称为浮游有孔虫，可用于评估地下氧气最低区的存在，海水温度等生活在海洋底部沉积物上或沉积物中的物种被称为底栖有孔虫，可用于重建底层水氧气浓度和通风。FARGO将使用国际海洋发现计划的沉积物来确定在关键的温暖间隔期间，浅太平洋OMZ氧气最低或“死亡”区（例如氧气水平太低而无法支持有氧生活的区域）的自然范围和强度是否发生了变化。原始的时间序列将为IPCC类型的气候模型模拟提供信息，并提供强有力的测试，以调查模拟在特定时间段内是否真实和正确，并确定改进模型模拟的途径。利用这些改进，FARGO将进行模拟未来，包括1.5和2度变暖的情景。为了提高对海洋脱氧的认识，FARGO计划针对科学同行，政策制定者和公众开展几项定制的影响和参与活动。为了减缓/减少脱氧和保护我们的海洋环境，FARGO计划与政府（苏格兰和英国）合作，制定区域立法，以管理英国沃茨水产养殖和农业的营养投入。

Oxygen is critical to the health of all higher life. In the oceans dissolved oxygen concentrations have declined by 2% since 1960, and are expected to continue to decline into the future in relation to man-made climate change. Future deoxygenation, along with overfishing, threatens the sustainability of economically important fisheries and marine ecosystems and will impact global biogeochemical cycles. It is therefore crucial that we obtain a well-informed view about what the future may hold.Current model simulations that predict the future carry considerable uncertainties; they do not all agree and grossly underestimate the document decrease of the last 50 years. This suggests the models are missing key interactions, calling for urgent action and a dedicated and inclusive scientific approach. FARGO provides such an approach by addressing why, and to what extent, seawater dissolved oxygen concentrations may change in a warming world. FARGO will study dissolved oxygen concentrations in the Pacific Ocean, the largest low-oxic water body in the current ocean, through an innovative and dedicated research programme incorporating a novel multi-proxy approach feeding IPCC-type climate model simulations across key warm time intervals:i- warmer climates across the closure of the American sea-way (4-15 million years);ii- warmer climates as future analogue (mid-Pliocene Warm Period, 3.3 to 3 million years ago);iii- Pleistocene warm intervals (interglacials of the last ca. 800,000 years). FARGO is structured into two phases: Phase I (years 1-4), and Phase II (years 5-7). The focus of the first four years is analytical, to advance method development and reconstruct time-series of oxygen concentrations and associated processes that drive changes (seawater warming, stratification, productivity, ventilation). The material FARGO will use to create these time-series involves the shells of microorganisms called foraminifera. Some species float near the ocean surface, called planktonic foraminifera, and can be used to assess the presence of subsurface oxygen minimum zones, seawater temperatures, etc. Species that live on or in sediments at the bottom of the ocean are termed benthic foraminifera and can be used to reconstruct bottom water oxygen concentrations and ventilation. FARGO will use sediments from the International Ocean Discovery Program to determine if there have been changes in the natural extent and intensity of the shallow Pacific Ocean OMZ oxygen minimum, or 'dead', zones (e.g. areas where oxygen levels are too low to support aerobic life), during the key warm intervals. The original time-series will feed the IPCC-type climate model simulations and provide robust tests to investigate if the simulations are realistic and correct for the specific time periods, and identify routes to improve the model simulations. Utilizing these improvements, FARGO will carry out simulations for future, including 1.5 and 2 degree warming scenarios.To raise awareness of ocean deoxygenation FARGO plans several bespoke impact and engagement activities aimed at scientific peers, policy makers, and the general public. To slow/reduce deoxygenation and protect our marine environment FARGO plans to work with government (Scottish and UK) to develop regional legislation to manage nutrient inputs from aquaculture and agriculture of UK waters.