Reconstructing Earth Energy Imbalance

重建地球能量失衡

• 批准号: 2202526
• 负责人: Gregory Hakim
• 金额: $ 48.06万
• 依托单位: University of Washington
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2022
• 资助国家: 美国
• 起止时间: 2022-08-01 至 2025-07-31
• 项目状态: 未结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=2202526&HistoricalAwards=false
• 关键词: Reconstructing; Earth; Energy; Imbalance

The net energy balance at the top of Earth’s atmosphere is critical for many important problems in climate science (e.g., climate sensitivity to changing greenhouse gas concentrations and modes of interaction between the atmosphere and ocean). Despite this central role, Earth’s energy budget has only been well observed for about the past 20 years. This short period of direct observation leaves a limited sample for evaluating important questions about climate variability, especially for distinguishing between variability that is externally forced versus internal to the climate system. While these questions can be approached using climate models, paleoclimate proxies provide the only encoding of climate information before the instrumental era, and thus are essential for quantifying climate variability, and particularly Earth’s energy imbalance on interannual, decadal and longer timescales. This project proposes to reconstruct Earth’s energy budget for the past 1000 years using paleoclimate data assimilation (PDA) method. This approach combines information from paleoclimate proxies with the physical constraints of climate models to reconstruct climate fields that are not directly observed by the proxies. The proposed research takes advantages of recent numerical simulations and preliminary-proof-of concept calculations to achieve this reconstruction.Specifically, the researchers will use an offline PDA, where the stationary statistics of long climate model simulations are used to supply physical constraints, and online PDA, where computationally efficient emulators of the climate models add dynamical “memory” to the reconstructions from proxies at earlier times. The researchers aim to construct outgoing shortwave and longwave radiation at the top of the atmosphere, and storage in terms of ocean heat content. The reconstructions will then be used to address a hypothesis on the relationship between spatial patterns of sea-surface temperature variability and energy imbalance. This project will provide a proxy-constrained estimate of Earth’s energy imbalance, both in ocean heat content and in the top-of-atmosphere radiative imbalance. A hierarchy of validation experiments, using satellite measurements, instrumental measurements, and historical simulations will provide confidence bounds on these estimates. The proposed research directly addresses important open problems in climate science, including pre-industrial energy imbalance needed for climate sensitivity, and the contribution of patterns of Pacific temperature variability to the planetary energy imbalance. The potential Broader Impacts include a gridded data product synthesizing paleoclimate proxy and model data for the top-of-atmosphere energy imbalance. Such a gridded millennial scale reconstruction will be made publicly available to the wide paleoclimate community for a widespread climate research, including detection and attribution-studies. This work will support the scientific training and professional development of one graduate student at the University of Washington.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.

地球大气层顶部的净能量平衡对于气候科学中许多重要问题（例如，气候对不断变化的温室气体浓度和大气与海洋之间相互作用模式的敏感性）至关重要。尽管如此，大约在过去的20年中，地球的能源预算才得到很好的观察。直接观察的短期时期为评估有关气候变异性的重要问题留下了有限的样本，尤其是在区分外部强迫与气候系统内部的变异性方面。尽管可以使用气候模型来解决这些问题，但古气候代理提供了在乐器时代之前唯一的气候信息编码，因此对于量化气候变异性，尤其是地球上的能量不平衡至关重要，尤其是对年龄段，年龄段和更长的时间尺度的能量不平衡。该项目的建议是使用古气候数据同化（PDA）方法在过去1000年中重建地球能源预算的提议。这种方法将来自古气候代理的信息与攀岩模型的物理约束结合在一起，以重建代理未直接观察到的气候场。拟议的研究利用了最新的数值模拟和初步的概念计算来实现此重建。具体来说，研究人员将使用脱机PDA，其中长攀岩模型模型的固定统计量用于提供物理约束，在线PDA，在线PDA，在线计算高效的模型，以添加了较早的“记忆”启用动态“记忆”，以添加动态“记忆”。研究人员的目标是在大气顶部构建外向的短波和长波辐射，并在海洋热含量方面进行存储。然后，这些重建将用于解决有关海面温度变化和能量不平衡空间模式之间关系的假设。该项目将在海洋热含量和大气顶部辐射不平衡的情况下提供对地球能量不平衡的代理估计。使用卫星测量，仪器测量和历史模拟的验证实验层次结构将在这些估计上提供置信界。拟议的研究直接解决了气候科学中重要的开放问题，包括气候灵敏度所需的工业前能量不平衡，以及太平洋温度变化对行星能量不平衡的模式的贡献。潜在的更广泛的影响包括扎根的数据产品合成古气候代理和模型数据的模型数据，以实现大气顶能量不平衡。这种扎根的千禧一代重建将公开向广泛的古气候社区公开，以进行广泛的气候研究，包括检测和属性研究。这项工作将支持华盛顿大学一名研究生的科学培训和专业发展。该奖项反映了NSF的法定任务，并通过使用基金会的知识分子优点和更广泛的影响评估标准来评估，被认为是宝贵的支持。