NERC-FAPESP: the Marine Gateways Project - Quantifying the causes and climatic consequences of the opening of the South Atlantic

NERC-FAPESP：海洋门户项目 - 量化南大西洋开放的原因和气候后果

• 批准号: NE/X002853/1
• 负责人: Rachel Flecker
• 金额: $ 8.85万
• 依托单位: University of Bristol
• 依托单位国家: 英国
• 项目类别: Research Grant
• 财政年份: 2022
• 资助国家: 英国
• 起止时间: 2022 至 无数据
• 项目状态: 未结题
• 来源: https://gtr.ukri.org/projects?ref=NE%2FX002853%2F1
• 关键词: NERC; FAPESP; Marine; Gateways; Project

Ocean circulation is driven by water masses with different densities. Much of this is generated at the ocean-continent boundary where near landlocked seas have a restricted connection with the global ocean, allowing them to evolve a different temperature or salinity. These marginal basins often form when continental plates coalesce - the Mediterranean today is a good example of this - or disaggregate - the opening of the South Atlantic around 100 million years as Gondwana broke apart is another. The evolution of these marine gateways therefore has a profound impact on the patterns of ocean circulation and its vigour. Changing palaeogeography is known to play a key role in major climate reorganisations such as the transition from greenhouse to icehouse conditions, and marine gateways are therefore the focus of several upcoming international scientific drilling projects.When marine gateways allow only very limited exchange, large volumes of evaporites may precipitate in the marginal seas. These salt giants, which are not forming in the world today can be sufficiently large to change the salinity of the global ocean. The most recent salt giant formed around 5 million years ago in the Mediterranean. Using isotopes that respond to the different proportions of ocean and river water feeding the marginal basin, integrated with box modelling and global climate simulations, it has been possible to reconstruct and quantify Mediterranean-Atlantic exchange and show that the major climate impact of this gateway evolution precedes evaporite precipitation by several million years. In this project we propose to develop and apply these techniques to the older and larger South Atlantic salt giant where there is still controversy over the location and timing of gateway evolution and hence the climatic impact of opening the South Atlantic. To do this we are extending an existing collaboration between Bristol and Utrecht where researchers have led much of the Atlantic-Mediterranean gateway research, to include researchers at the University of Sao Paulo who have essential expertise in the palaeogeography and chronology of the South Atlantic salt-bearing successions. This is therefore a joint NERC-FAPESP global partnership seedcorn application.Over two years we propose to undertake fieldwork in Brazil led by the University of Sao Paulo, pilot isotope analyses and GCM analysis of existing global climate simulations at the University of Bristol, in parallel with box-modelling at Utrecht University. An early meeting in Bristol to review the initial pilot data will be followed by a mid-project model-data integration workshop in Sao Paulo. The workshop will be open to the wider research community in South America and we will particularly encourage the involvement of Early Stage Researchers. In addition, we will support Sao Paulo PhD students to apply for internship scholarships (FAPESP-BEPE) in order to be actively involved in the project. The last phase of this project will draw in researchers involved in marine gateway research associated with current scientific drilling projects, three of which are led by UK scientists. The final meeting in Bristol will be a forum both for presenting the scientific results of the project and for initiating an EU COST-Action application to support on-going community-building and collaborative research activities. This is designed to support and expand the scientific community engaged with long-term scientific drilling projects focused on marine gateways.

海洋循环是由密度不同的水量驱动的。其中大部分是在内陆海洋附近的海洋边界中产生的，与全球海洋有限制的联系，从而使它们能够进化出不同的温度或盐度。这些边缘盆地经常形成，当大陆板融合在一起时 - 今天的地中海是一个很好的例子 - 或分类 - 随着冈瓦纳（Gondwana）破裂，南大西洋的开放大约是1亿年。因此，这些海洋门户的演变对海洋循环及其活力的模式产生了深远的影响。众所周知，不断变化的古地理学在重大气候重组（例如从温室到冰舍条件的过渡）中起着关键作用，因此，海洋门户是几个即将到来的国际科学钻探项目的重点。当海上船只只允许非常有限的交换时，大量的蒸发物可能会在Marginal Seaseas中降临。这些盐巨人在当今世界没有形成的盐巨头可以很大，可以改变全球海洋的盐分。最近的盐巨人大约在500万年前在地中海组成。使用与盒子建模和全球气候模拟集成的海洋和河水供水的不同比例的同位素，可以重建和量化地中海 - 大西洋交换，并表明该网关进化的重大气候影响预先达到数百万年的蒸发量。在这个项目中，我们建议将这些技术开发并应用于较老的南大西洋盐巨人，在那里仍然存在争议，在Gateway Evolution的位置和时机上仍然存在争议，从而对开放南大西洋的气候影响产生了影响。为此，我们正在扩展布里斯托尔和乌得勒支之间的现有合作，研究人员带领大部分大西洋 - 梅特拉尼亚的网关研究包括萨奥保罗大学的研究人员，他们在南大西洋盐盐的古地理和年表方面具有重要的专业知识。因此，这是一项联合NERC-FAPESP全球伙伴关系种子康的应用。两年来，我们建议在圣保罗大学，飞行员同位素分析和GCM分析布里斯托尔大学现有全球气候模拟的GCM分析，并与Utrecht University的Box-Modelling进行现有的全球气候模拟。在布里斯托尔举行的早期会议审查最初的飞行员数据，然后将在圣保罗举行的中型模型DATA集成研讨会。该研讨会将向南美更广泛的研究社区开放，我们将特别鼓励早期研究人员参与。此外，我们将支持圣保罗博士学生申请实习奖学金（FAPESP-BEPE），以便积极参与该项目。该项目的最后阶段将吸引参与与当前科学钻探项目相关的海洋网关研究的研究人员，其中三个由英国科学家领导。在布里斯托尔举行的最后会议将是一个论坛，既可以介绍该项目的科学结果，又要启动欧盟成本措施申请，以支持正在进行的社区建设和协作研究活动。这旨在支持和扩展与以海洋门户为重点的长期科学钻探项目相关的科学界。