Interacting ice Sheet and Ocean Tipping - Indicators, Processes, Impacts and Challenges (ISOTIPIC)

冰盖和海洋倾覆的相互作用 - 指标、过程、影响和挑战 (ISOTIPIC)

• 批准号: NE/Z503344/1
• 负责人: Antony Payne
• 金额: $ 216万
• 依托单位: University of Liverpool
• 依托单位国家: 英国
• 项目类别: Research Grant
• 财政年份: 2024
• 资助国家: 英国
• 起止时间: 2024 至 无数据
• 项目状态: 未结题
• 来源: https://gtr.ukri.org/projects?ref=NE%2FZ503344%2F1
• 关键词: Interacting; ice; Sheet; Ocean; Tipping

The aim of this project is to understand the processes controlling key tipping points (TPs) associated with the oceans and ice sheets, and assess their potential impacts on society and the global Earth system. The specific Tipping Elements (TEs) to be considered are related to the Atlantic Ocean Meridional Overturning (AMOC), the Greenland ice sheet (GrIS), coastal upwelling in the Southern Ocean (SO) and the Antarctic ice sheet (AIS). These TEs are a coherent subset of the TEs widely discussed in the literature. They (a) share relatively long timescales and therefore similar analysis methodologies are likely to be appropriate; (b) are potentially linked in tipping cascades such as the SO circulation interacting with AIS instability and GrIS meltwater impacting AMOC stability, as well as potential bi-polar interactions; and (c) share the hugely important impact of sea level rise.Work Package 1 focuses on AMOC and GrIS and their interaction; while Work Package 2 focuses on AIS and interactions with the SO. The overall objective in both is to constrain the circumstances under which the relevant TEs either have been or could potentially be triggered in the future; as well as addressing the long-term response of the TE to assess, in particular, under what circumstances the tipping becomes truly irreversible. These improvements in understanding lead into the identification of potential Early Warning indicators in Work Package 3, while Work Package 4 will assess the societal and climatic impacts of tipping focusing on projected regional sea level rise and global climate.The Topic A call identifies five research questions, all of which should be tackled.What are the global and regional impacts and risks associated with key climate TPs? Work Package 4 focuses on impact, in particular the key impact of regional sea level rise with links to the communities designing storm surge barriers and developing adaptive management approaches. This work package will also investigate the wider impacts of tipping on global climate using UKESM, for instance on changing monsoon patterns.Is there evidence for abrupt changes and TPs in the latest ESMs? Many of the current generation of ESMs (in particular those used in CMIP6) do not contain the appropriate coupling for ice sheet TPs so that we will use models of the ice sheets either as standalone or coupled to regional ocean and atmosphere models to assess tipping. Forcing for these experiments will come from both UKESM and the wider CMIP6 ensemble.How do the risks of TPs vary in scenarios that overshoot the Paris 1.5°C and 2°C targets? Our Work Packages 1 and 2 will determine thresholds for tipping for TPs associated with both ice sheets and the Atlantic Meridional Overturning Circulation, which can then be related back to the Paris targets.How do we design the best early warning systems for specific TPs such as Atlantic meridional overturning circulation shutdown, ice-sheet collapse, or forest dieback? Our approach in Work Package 3 is to test a range of statistical early warning indicators by applying them to the outputs of models that are known to tip to determine which indicators are able to predict this tipping and on what timescales.Where is there evidence of changing system resilience in observational records? Having tested these indicators, Work Package 3 will apply them to observational records.

该项目的目的是了解控制与海洋和冰盖相关的关键临界点（TP）的过程，并评估其对社会和全球地球系统的潜在影响。要考虑的具体临界点（TE）是相关的。大西洋经向翻转 (AMOC)、格陵兰冰盖 (GrIS)、南大洋沿海上升流 (SO) 和南极冰盖 (AIS) 这些 TE 是连贯子集。 TE 在文献中得到广泛讨论，它们 (a) 具有相对较长的时间尺度，因此类似的分析方法可能是合适的；(b) 可能与倾倒级联相关，例如 SO 循环与 AIS 不稳定性和 GrIS 融水影响 AMOC 稳定性。以及潜在的两极相互作用；(c) 共同承担海平面上升的极其重要的影响。工作包 1 侧重于 AMOC 和 GrIS 及其相互作用；而工作包 2 则侧重于 AIS 和相互作用；两者的总体目标是限制相关 TE 已经或可能在未来触发的情况，并解决 TE 的长期响应问题，特别是在以下情况下：这些理解导致工作包 3 中潜在的预警指标的确定，而工作包 4 将评估倾倒改进的社会和气候影响，重点关注预计的区域海平面上升和全球气候。主题 A 调用标识五个研究问题，所有这些问题都应该得到解决。与关键气候目标相关的全球和区域影响和风险是什么？工作包 4 重点关注影响，特别是与设计风暴的社区相关的区域海平面上升的关键影响。该工作包还将使用 UKESM 调查倾倒对全球气候的更广泛的影响，例如对变化的季风模式的影响。当前一代的许多 ESM 中是否有突变和 TP 的证据？的ESM（特别是 CMIP6 中使用的 ESM）不包含冰盖 TP 的适当耦合，因此我们将使用冰盖模型作为独立模型或与区域海洋和大气模型耦合来评估这些实验的倾覆力。来自 UKESM 和更广泛的 CMIP6 整体。在超过巴黎 1.5°C 和 2°C 目标的情况下，TP 的风险有何变化？我们的工作包 1 和 2 将确定阈值与冰盖和大西洋经向翻转环流相关的TP的倾斜，然后可以与巴黎目标相关联。我们如何为特定的TP设计最佳的预警系统，例如大西洋经向翻转环流关闭、冰盖崩塌或森林枯死？我们在工作包 3 中的方法是测试一系列统计预警指标，将其应用于已知的倾倒模型的输出，以确定哪些指标能够预测这种倾倒以及什么因素观测记录中的系统弹性变化的证据在哪里？测试完这些指标后，工作包 3 将把它们应用到观测记录中。