P2C2: Bayesian Detection of Holocene Abrupt Transitions in Proxy Records and Climate Model Simulations

P2C2：代理记录和气候模型模拟中全新世突变的贝叶斯检测

• 批准号: 2102949
• 负责人: Christopher Guiterman
• 金额: $ 38.85万
• 依托单位: University of Colorado at Boulder
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2021
• 资助国家: 美国
• 起止时间: 2021-09-01 至 2024-08-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=2102949&HistoricalAwards=false
• 关键词: P2C2; Bayesian; Detection; Holocene; Abrupt

There is a lack of understanding of when and where abrupt climate events occurred in the past, and what are the drivers of such rapid climate shifts. This project seeks to identify the spatial and temporal components of abrupt climate transitions during the Holocene, the current interglacial period (~10.000 years). The researchers will combine paleoclimate data and models to assess the ability to simulate rapid climate shifts and predict future changes. This project will leverage several recent developments, including a dramatic increase in the number of high-resolution Holocene paleoclimate records over the past decade, the development of new statistical techniques to detect changepoints in paleoclimate records (e.g., temperature or rainfall) and handle uncertainties of the paleoclimate data, and the availability of climate simulations with increasingly realistic drivers and processes.The work aims to address three questions: (1) What is the spatial and temporal pattern of abrupt changes during the Holocene? Are they organized in time and space, or do they occur more stochastically? (2) What are the forcings (e.g., orbital forcing, solar variability, volcanic eruptions) and climate system nonlinearities (e.g., feedbacks, thresholds) that produce Holocene abrupt events? (3) Do coupled climate models simulate abrupt climate changes of the types observed in the Holocene paleoclimate record, or are models more stable?To answer these question, researchers suggest to (1) use Bayesian changepoint detection to objectively identify rapid shifts in a large data set of Holocene proxy records while accounting for age, proxy, and methodological uncertainties, (2) aggregate these results into a systematic and integrated view of transitions in time and in space, (3) apply the same algorithm to several transient simulations of Holocene climate in order to test hypotheses about the relative roles of external forcing and stochastic internal variability in generating past abrupt events.The potential Broader Impacts include a better characterization of abrupt climate events in the past, and an evaluation of their predictability with climate models. This project will generate curated paleoclimate data that will support the Findability, Accessibility, Interoperability, and Reusability (Fair) data management principles and federal data strategy. The project will also provide training and support for one post-doctoral research and an undergraduate student. Additionally, undergraduate students will be involved through internship programs in Boulder, including the NOAA Hollings Program, the NOAA Educational Partnership Program with Minority Serving Institutions, and the UCAR Significant Opportunities in Atmospheric Science program. The researchers will create new content for the “Paleo Perspective on Abrupt Climate Change” webpage hosted by the WDS-Paleo and NOAA’s National Centers for Environmental Information (NCEI), highlighting the findings from the project. This Paleo Perspectives are aimed at a general audience and explain how paleoclimatology data provide a long baseline of past change needed to understand the natural variability of the Earth’s climate over a variety of timescales. The perspectives also provide a variety of links to scientific research results and datasets.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.

人们对过去气候突变事件发生的时间和地点以及这种快速气候变化的驱动因素缺乏了解。该项目旨在确定全新世，即目前的间冰期（约10.000年）期间气候突变的空间和时间组成部分。研究人员将结合联合收割机古气候数据和模型，评估模拟快速气候变化和预测未来变化的能力。该项目将利用最近的几项发展，包括过去十年来高分辨率全新世古气候记录数量的急剧增加，新的统计技术的发展，以检测古气候记录中的变化点（例如，气候模拟的目的是解决以下三个问题：（1）全新世气候突变的时空格局是什么？它们是在时间和空间上有组织的，还是随机发生的？(2)力是什么（例如，轨道强迫、太阳变率、火山爆发）和气候系统非线性（例如，反馈，阈值），产生全新世突发事件？(3)耦合气候模式是否模拟了全新世古气候记录中观测到的气候突变类型，还是模式更稳定？为了回答这些问题，研究人员建议（1）使用贝叶斯变点检测来客观地识别全新世代理记录的大型数据集的快速变化，同时考虑年龄，代理和方法的不确定性，（2）将这些结果汇总为时间和空间转换的系统和综合视图，（三）将同样的算法应用于全新世气候的几个瞬态模拟，以检验关于外部强迫和随机内部变率在产生过去突发事件中的相对作用的假设。潜在的更广泛的影响包括一个更好的对过去突发性气候事件的特征描述，以及用气候模式对其可预测性的评估。该项目将生成精心策划的古气候数据，支持可查找性、可访问性、互操作性和可重用性（公平）数据管理原则和联邦数据战略。该项目还将为一名博士后研究人员和一名本科生提供培训和支持。此外，本科生将参与博尔德的实习计划，包括NOAA Hollings计划，NOAA与少数民族服务机构的教育合作计划，以及UCAR大气科学计划的重要机会。 研究人员将为WDS-Paleo和NOAA国家环境信息中心（NCEI）主办的“古气候变化视角”网页创建新内容，突出该项目的研究结果。本《古气候透视》面向普通读者，解释古气候学数据如何提供过去变化的长期基线，以了解地球气候在不同时间尺度上的自然变化。该奖项反映了NSF的法定使命，并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，被认为值得支持。