Southern OceaN optimal Approach To Assess the carbon state, variability and climatic Drivers (SONATA)

南大洋评估碳状态、变异性和气候驱动因素的最佳方法 (SONATA)

基本信息

批准号：
NE/P021298/1
负责人：
Andrew Watson
金额：
$ 35.31万
依托单位：
UNIVERSITY OF EXETER
依托单位国家：
英国
项目类别：
Research Grant
财政年份：
2017
资助国家：
英国
起止时间：
2017 至无数据
项目状态：
已结题

来源：
https://gtr.ukri.org/projects?ref=NE%2FP021298%2F1
关键词：
Southern OceaN optimal Approach Assess

项目摘要

The Southern Ocean (SO) is the most exciting and extreme region of the world ocean, with the strongest winds, coldest temperatures, and most intense storms. It is believed also to be among the largest 'sink' for atmospheric CO2, accounting for about one third of the uptake of CO2 by the global ocean and nearly one tenth of the global emissions of CO2 on average each year. Thus the evolution of the SO carbon sink has the potential to alter the rate and extent of climate change.In spite of its importance, we don't know the state, variability, or climatic drivers of the contemporary SO carbon sink and there is much controversy over its recent evolution. The climate of the SO has been changing over recent decades: in particular, winds have intensified, (attributed in part to the depletion of stratospheric ozone and in part to increasing temperature gradients arising from climate change), ocean acidification is occurring, and there is a long term decline in krill stocks. These effects take place on top of large natural variability and poorly quantified climatic trends.SONATA will achieve a step change in our understanding of the contemporary SO carbon sink by delivering new data and new insights, integrating observations from the ocean, from the atmosphere, and model results. We will develop three complementary streams of research, an 'Oceanic', an 'Atmospheric', and a 'Processes and drivers' view, and will bring them together using advanced mathematical frameworks to provide a single assessment with multiple constraints and reduction of uncertainties.The Oceanic view will use existing and new observations of ocean carbon. We will undertake a new calibration experiment to better assess the large number of pH measurements now being made by about 200 sophisticated profiling floats introduced by the US SOCCOM programme. These have the potential to greatly increase the number of observations that can be used to calculate air-sea CO2 fluxes, but only if adequately calibrated. In addition we will develop and use a new technique to construct estimates of the seasonal and temporal evolution of the air-sea flux, using a model of the upper water column constrained with available hydrographic and carbon-system observations. The Atmospheric view will collect new atmospheric CO2 data in remote SO locations comprising Halley Station (75S), the Falkland Islands (51S), and aboard the BAS research ship James Clark Ross; new atmospheric O2 data will come from a ship track that repeats a SO transect every 8 weeks, as well as from Halley Station in coastal Antarctica. Using these data and an inverse framework approach, SONATA will provide an independent assessment of the SO carbon sink, which will deliver particularly on the geographic distribution of the changes, with O2 data helping to inform the drivers.The Processes and drivers view will use two climate-scale carbon models and a series of hindcast simulations to identify the relative contributions of (a) atmospheric CO2 concentration, (b) natural climate variability, (c) climate change, and (d) stratospheric ozone depletion to recent SO carbon trends and variability. Ocean and atmosphere observations, including new data from SONATA and SOCCOM, will be used to optimise the model and validate the results. Idealised forcing with climate models will provide the 'fingerprints' of climatic drivers that are needed to understand the observed patterns of change.Finally the three streams of research will be integrated using a Bayesian fusion mathematical approach that considers the strengths and weaknesses of each stream of information and minimises the joint uncertainty. The SO ocean carbon sink will be assessed annually in this way. We will then test the added value of including new streams of observations in the future, including from floats, gliders, drifters, Autonomous Surface Vehicles, additional ground-based observations and satellite CO2 data.

南大洋（So）是世界上最令人兴奋，最极端的地区，风，最冷的温度和最激烈的风暴。据信它也是大气二氧化碳最大的“下水道”之一，约占全球海洋吸收二氧化碳的三分之一，而每年平均占全球二氧化碳排放量的十分之一。因此，So碳汇的演变有可能改变气候变化的速度和程度。尽管重要性，我们不知道当代的国家，可变性或气候驱动因素，因此碳汇，并且在其最近的进化中存在很大争议。近几十年来，SO的气候一直在发生变化：特别是，风增强（部分归因于平流层臭氧的消耗，部分原因是由于气候变化而引起的温度梯度升高），海洋酸化发生，并且长期下降了磷虾。这些效果发生在较大的自然变异性和量化不佳的气候趋势之上。Sonata将通过提供新的数据和新见解，从海洋，大气中整合观察结果以及模型结果来实现我们对当代So Sink的理解。我们将开发三个互补的研究流，一个“海洋”，“大气”和“过程和驱动程序”的观点，并将使用先进的数学框架将它们聚集在一起，以提供单一的评估，并减少不确定性。我们将进行一项新的校准实验，以更好地评估美国SOCCOM计划引入的大约200个复杂分析的浮点数现在进行的大量pH测量。这些可能会大大增加可用于计算空气二氧化碳通量的观测值的数量，但仅当经过充分校准时。此外，我们将使用一种新技术来构建空气通量季节性和时间演变的估计，并使用约束的上水柱模型受到可用的水文和碳系统观测的约束。大气景观将在遥远的偏远地区收集新的大气二氧化碳数据，因此包括Halley Station（75s），Falkland Islands（51s）和BAS研究船James Clark Ross的位置；新的大气O2数据将来自每8周重复一次如此横断的船舶轨道，以及南极沿海地区的Halley Station。 Using these data and an inverse framework approach, SONATA will provide an independent assessment of the SO carbon sink, which will deliver particularly on the geographic distribution of the changes, with O2 data helping to inform the drivers.The Processes and drivers view will use two climate-scale carbon models and a series of hindcast simulations to identify the relative contributions of (a) atmospheric CO2 concentration, (b) natural climate variability, (c) climate change, and (d) stratospheric臭氧耗竭近期碳趋势和可变性。海洋和大气观测，包括来自奏鸣曲和SOCCOM的新数据，将用于优化模型并验证结果。使用气候模型的理想化强迫将提供气候驱动因素的“指纹”，以了解观察到的变化模式所需的“指纹”。从最后的角度来看，将使用贝叶斯融合数学方法进行整合，以考虑每种信息流的优势和弱点，并将关节不确定。 SO海洋碳水槽将每年以这种方式进行评估。然后，我们将测试将来包括新观测流的附加值，包括来自浮子，滑翔机，边缘，自动表面车辆，其他地面观测和卫星CO2数据。