Collaborative Research: Assessing the Causal Influence of Atmospheric Opacity and Sea Ice on Arctic Warming in a Novel Circulation-controlled Framework

在过去的40年里，北极变暖的程度超过了地球上的任何其他地区。这种大于全球的北极变暖预计将继续对人类人口、生态系统和基础设施产生持久影响。虽然导致北极变暖超过全球范围的基本机制是已知的，但控制北极变暖幅度的机制更难约束。该项目的重点是从1980年到2060年已经并将控制北极变暖的措施。通过指定相对受约束较好的大气条件的各个方面(风)，我们将更好地理解更难从观测上约束的驱动因素(云和海冰厚度)的重要性。这项工作将导致我们在理解什么控制和不控制北极变暖方面取得变革性的进展。本项目专注于以下研究问题：海冰厚度和大气不透明度(即云)对近期和近期北极变暖速率的因果影响是什么？这一研究问题和相关假设将在美国国家科学基金会资助的地球系统模型(共同体地球系统模型，CESM)中进行评估，该模型以观测为指导，包括最近一年的现场大量观测(北极气候研究多学科漂移观测站)。中心成果将是利用一种限制大范围大气环流的新方法，量化两种平均状态属性(大气不透明度、海冰厚度)对1980年至2060年北极变暖速度的因果影响。将围绕驾驶问题开发一个为期两周的探究式初中课程：你所在地区的天气可能会受到北极的影响？该课程将由专家审查，并通过虚拟教师研讨会传播，使北美数百名教师能够将当前的北极研究带入课堂。该项目还将积极邀请早期职业科学家参与研究，其中包括一名博士生和两名本科生暑期研究经验(REU)暑期学生。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。

Over the last 40 years, the Arctic has warmed more than any other region on the planet. This greater-than-global Arctic warming is projected to continue with lasting impacts on human populations, ecosystems, and infrastructure. While the fundamental mechanisms that lead to greater-than-global Arctic warming are known, the mechanisms controlling the magnitude of Arctic warming are harder to constrain. This project is a focused effort on what has and will control Arctic warming from 1980 to 2060. By specifying aspects of the atmospheric conditions that are relatively well constrained (the winds), we will better understand the importance of drivers that are harder to constrain observationally (clouds and sea ice thickness). This work will lead to transformational advances in our understanding of what does and does not control Arctic warming.This project is focused on the following research question: What is the causal influence of sea ice thickness and atmospheric opacity (i.e., clouds) on recent and near-future Arctic warming rates? This research question and associated hypotheses will be assessed in a well-established NSF-funded earth system model (Community Earth System Model, CESM) guided by observations including those from a recent year-long field campaign with substantial in situ observations (Multidisciplinary drifting Observatory for the Study of Arctic Climate, MOSAiC). The central outcome will be quantifying the causal influence of two mean state properties (atmospheric opacity, sea ice thickness) on Arctic warming rates from 1980 to 2060 using a novel ‘wind-nudging’ methodology that constrains the large-scale atmospheric circulation. An inquiry-based 2-week middle-high school curriculum will be developed centered around the driving question: How might weather in your area be impacted by the Arctic? The curriculum will be reviewed by experts and disseminated through virtual teacher workshops, enabling hundreds of teachers in North America to bring current Arctic research into their classrooms. The project will also actively engage early career scientists in the research including a Ph.D. student and two summer Research Experience for Undergraduates (REU) summer students.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.