Drivers and Impacts of North Atlantic freshwater and heat fluxes unsettling modern-day climate (DIMSUM)

北大西洋淡水和热通量扰乱现代气候的驱动因素和影响 (DIMSUM)

• 批准号: 2401413
• 负责人: An Nguyen
• 金额: $ 46.35万
• 依托单位: University of Texas at Austin
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2023
• 资助国家: 美国
• 起止时间: 2023-12-01 至 2026-03-31
• 项目状态: 未结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=2401413&HistoricalAwards=false
• 关键词: Drivers; Impacts; North; Atlantic; freshwater

This is a project jointly funded by the National Science Foundation’s Directorate for Geosciences (NSF/GEO) and the National Environment Research Council (NERC) of the United Kingdom (UK) via the NSF/GEO-NERC Lead Agency Agreement. This Agreement allows a single joint US/UK proposal to be submitted and peer-reviewed by the Agency whose investigator has the largest proportion of the budget. Upon successful joint determination of an award recommendation, each Agency funds the proportion of the budget that supports scientists at institutions in their respective countries.Exchanges between the Arctic and North Atlantic (NA) of heat and freshwater (FW) impact the large-scale NA and global climate. The complex interactions and feedbacks span many spatial and temporal scales from short-term and local to multi-decadal and across ocean basins. An accurate understanding of the mechanisms impacting heat and FW fluxes into the NA, and subsequent ocean mixing that sets surface properties, is therefore of critical importance for assessing the risks of rapid NA climate change. This project will use a comprehensive set of observation- and model-based products and tools to significantly advance our understanding of NA heat and FW variations, elucidating drivers, exposing atmospheric feedbacks, and exploring subsequent impacts on larger-scale weather and climate. Understanding the intricate relationship between climate change and weather patterns is of paramount societal significance. This project plays a pivotal role in addressing this challenge by shedding light on the behavior of a major, yet uncertain, component within the system, ultimately contributing to more informed climate adaptation and mitigation strategies. The research team features a high proportion of female scientists and two PIs (Lenn & Nguyen) from historically-under-represented global south ethnic groups in geosciences. The project provides training and leadership opportunities for early-career female scientists Pillar and Schulz (UT Austin). This project will investigate drivers and impacts of heat and FW changes in the NA by capitalizing on a comprehensive set of observation- and model-based products and tools, in particular the OSNAP and RAPID mooring arrays, coupled high-resolution model simulations, and the Arctic Subpolar gyre sTate Estimate (ASTE). ASTE, a dynamically consistent model-data synthesis with inbuilt adjoint capability, provides a very unique and powerful tool for investigation of causal drivers of NA dynamics and variability. Combining these products with novel statistical tools and state-of-the-art analysis techniques, will help the assess mechanisms of change up- and downstream of the arrays and evaluate their climate feedbacks, including potential drivers and impacts of a rapid Beaufort Gyre FW release. The three research objectives of the project are (O1) Quantify heat and FW budgets, using observations (e.g., OSNAP and RAPID arrays, Argo, satellite-derived), model-data synthesis (ASTE) and coupled models; (O2) Elucidate mechanisms driving changes in heat and FW budgets and creating rapid climate change thresholds; (O3) Assess impacts of ocean heat and FW changes on large-scale climate, including the risk of rapid change. A novel aspect of this approach pairs assessment of watermass transformation budgets with potential energy diagnostics and adjoint sensitivity mappings. These complementary perspectives are jointly accessible only within the state estimation framework and will shed new insights into the mechanisms via which remote forcings can reshape NA watermass distribution and destabilize convection. Additionally, the work will reveal potential predictability within the NA.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.

这是一个由国家科学基金会地球科学理事会（NSF/GEO）和联合王国国家环境研究理事会（NERC）通过NSF/GEO-NERC牵头机构协议联合资助的项目。该协议允许美国/英国提交一份联合提案，并由研究者拥有最大预算比例的机构进行同行评审。在成功联合确定奖励建议后，每个机构都为各自国家机构的科学家提供一定比例的预算资金。北极和北大西洋（NA）之间的热量和淡水（FW）交换对大规模NA和全球气候产生影响。复杂的相互作用和反馈跨越许多空间和时间尺度，从短期和局部到数十年和跨海洋盆地。因此，准确了解影响热量和FW通量进入NA的机制，以及随后的海洋混合设置表面特性，对于评估快速NA气候变化的风险至关重要。该项目将使用一套全面的基于观测和模型的产品和工具，以显着推进我们对NA热和FW变化的理解，阐明驱动因素，暴露大气反馈，并探索对大尺度天气和气候的后续影响。了解气候变化和天气模式之间的复杂关系具有重要的社会意义。该项目通过揭示系统内一个主要但不确定的组成部分的行为，在应对这一挑战方面发挥着关键作用，最终有助于制定更明智的气候适应和缓解战略。该研究团队的特点是女性科学家和两名PI（Lenn Nguyen）的比例很高，他们来自地球科学领域历史上代表性不足的全球南方种族群体。该项目为早期职业女性科学家支柱和舒尔茨（UT奥斯汀）提供培训和领导机会。该项目将通过利用一套全面的基于观测和模型的产品和工具，特别是OSNAP和RAPID系泊阵列，耦合高分辨率模型模拟和北极副极地环流状态估计（ASTE），调查NA中热量和FW变化的驱动因素和影响。ASTE是一个具有内在伴随能力的动态一致的模型数据合成，为NA动态和变异性的因果驱动因素的研究提供了一个非常独特和强大的工具。将这些产品与新的统计工具和最先进的分析技术相结合，将有助于评估阵列上游和下游的变化机制，并评估其气候反馈，包括快速博福特环流FW释放的潜在驱动因素和影响。该项目的三个研究目标是（O 1）量化热量和FW预算，使用观察（例如，OSNAP和RAPID阵列、Argo、卫星衍生的）、模式数据合成（ASTE）和耦合模式;（O2）阐明驱动热量和FW收支变化的机制并建立快速气候变化阈值;（O3）评估海洋热量和FW变化对大尺度气候的影响，包括快速变化的风险。这种方法的一个新的方面对评估水团变换预算与势能诊断和伴随灵敏度映射。这些互补的观点是共同访问只有在状态估计框架内，并通过远程强迫可以重塑NA水团分布和对流不稳定的机制，将脱落新的见解。该奖项反映了NSF的法定使命，并被认为值得通过使用基金会的知识价值和更广泛的影响审查标准进行评估来支持。