Collaborative Research: Prospects and limitations of predicting a potential collapse of the Atlantic meridional overturning circulation

这项研究将解决地球气候变化的一个关键方面：大西洋经向翻转环流的潜在崩溃，海洋通过该环流向大气提供热量和水分。这项研究将仔细研究最近关于这种崩溃可能发生在21世纪中叶的主张。这一挑战将通过将气候统计指数与简化的理论模型(动力系统)和综合气候模型进行比较来实现。这些模型将调查目前的全球海洋环流有多稳定，以及它是否会在几十年内崩溃。该项目将支持职业生涯早期的研究人员、一名博士后学者和一名研究生。这项研究将寻求提高我们对大西洋子午线翻转环流(AMOC)潜在崩溃的理解。这项研究将探索将临界减速(CSD)概念应用于AMOC代理或指纹的局限性。CSD的框架表明，当动力系统接近突变时，它们对扰动的反应可能会很慢。特别是，这项研究将挑战最近在CSD框架下获得的命题，即AMOC将在21世纪中叶崩溃。这项研究的进一步探索将深入到一般动力系统的应用，以及超越CSD限制的方法的实施，以评估AMOC的稳定性条件。这项研究将试图调和统计指标与a)理想化模型和b)综合模型结果之间的差异。这些差异包括理想化模型能够表示AMOC的突变，而综合模型似乎不能表示这种突变。作为更广泛的影响，该项目涉及一个与气候变化理解至关重要的主题。它还将支持一名研究生和一名博士后学者，将为早期职业生涯的科学家提供合作机会，并将把大约100名来自经济低迷背景的学生带到北卡罗来纳州威尔明顿大学的一个学习夏令营。该奖项反映了NSF的法定使命，并通过使用基金会的智力优势和更广泛的影响审查标准进行评估，被认为值得支持。

This study will address a key aspect of climate change on Earth: the potential collapse of the Atlantic Meridional Overturning Circulation through which the ocean provides heat and moisture to the atmosphere. The study will scrutinize recent propositions that such collapse could occur in the middle of the 21st century. Such challenge will be effected by comparing statistical indices of climate to simplified theoretical models (dynamical systems) and to comprehensive climate models. These models will investigate how stable the current global circulation of the ocean is and whether it can collapse over a few decades. The project will support early-career researchers, one postdoctoral scholar, and one graduate student. It will also seek to reach undergraduate students from economically depressed backgrounds.This study will seek to improve our understanding related to potential collapses of the Atlantic Meridional Overturning Circulation (AMOC). The study will explore limitations of applying Critical Slowing Down (CSD) concepts to AMOC proxies or fingerprints. The framework of CSD indicates that dynamical systems may respond slowly to perturbations as they approach an abrupt transition. Particularly, this study will challenge the recent proposition, obtained with a CSD framework, that the AMOC will collapse in the mid-21st century. Further explorations of this study will delve into the application of dynamical systems in general, and into implementation of methods that go beyond the limitations of CSD to assess stability conditions of the AMOC. The study will attempt to reconcile discrepancies between statistical indicators and results from a) idealized models, and b) comprehensive models. These discrepancies consist of idealized models being able to represent abrupt transitions of AMOC, while comprehensive models seem to be unable to represent such transitions. As Broader Impacts, the project addresses a topic of crucial relevance to climate change understanding. It also will support one graduate student and one postdoctoral scholar, will provide collaborative opportunities to early-career scientists, and will take approximately 100 students from economically depressed backgrounds to a learning camp at the University of North Carolina Wilmington.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.