Collaborative Research: P2C2--Multi-Time-Scale Climate Dynamics in California (CA): An Integrated Multi-Proxy Stalagmite, Monitoring, and Modeling Approach

合作研究：P2C2——加利福尼亚州（CA）的多时间尺度气候动力学：一种综合的多代理石笋、监测和建模方法

• 批准号: 1804747
• 负责人: Clay Tabor
• 金额: $ 13.33万
• 依托单位: University of Connecticut
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2018
• 资助国家: 美国
• 起止时间: 2018-09-01 至 2023-08-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1804747&HistoricalAwards=false
• 关键词: Collaborative; Research; P2C2; Multi; Time

Southwest North America (SWNA) is one of the world's most climatically sensitive regions with inherently variable hydroclimate. Much evidence exists for repeated, large regime shifts in this region's hydroclimate at the sub-decadal to millennial-scale during the last glacial cycle and Holocene, but the mechanisms driving this change remain uncertain. In the context of this past variability and the potential magnitude of future climate change, a refined understanding of the hydroclimate response to perturbation and of the underlying driving mechanisms is needed. The research team aims to generate a set of multiproxy calcite and fluid inclusion records, resolved at the sub-decadal to centennial-scale, for four stalagmites from the central and southern Sierra Nevada, CA that span the last deglaciation through Holocene. By integrating high-precision Uranium-Thorium dating, cave monitoring, multi-stalagmite records, and Earth system modeling (single-forcing water-isotope tracking simulations), the research team will (1) evaluate how North Pacific storm track behavior and the resulting precipitation signal is archived in the stalagmite proxy records, and (2) apply this knowledge to investigating the mechanisms underlying this precipitation response in the context of the changing environmental forcings of the past 21,000 years. Integration of the new Sierra Nevada records with complementary stalagmite records being developed for coastal and northern CA will permit a regionally expansive investigation of the mechanisms influencing storm track behavior and precipitation patterns in SWNA. Data-model comparisons with the new isotope-enabled Transient Climate Evolution since 21-ka simulations (iTraCE-21ka model) will provide further insight into the global drivers and response time of climate in the western U.S. to different forcings. An integrated cave monitoring-stalagmite proxy-water isotope modeling approach could provide (1) insight into how climate and karst processes imprint stalagmite proxy records, and (2) much needed quantitative constraints on how paleo-precipitation in the western U.S. responded to evolving climate conditions.The potential Broader Impacts (B.I.) include three outreach activities to integrate under-represented high school and undergraduate students into the Sierran stalagmite project and distribute the findings to the public. (1) A team (n=8) of undergraduate students will be formally integrated into the research through the development of a Vertically Integrated Project (VIP) at UC Davis (C3Climate Change in California). This program, supported by a grant from the Helmsley Charitable Trust to the VIP Consortium (UCD is one of 16 universities that participate), will involve weekly seminars, peer-mentoring, and team-based research in the cave-monitoring component. (2) A climate science-based curriculum will be developed for Vacaville (CA) High School, a Hispanic serving institution. The curriculum will integrate aspects of the stalagmite study and target development of critical-thinking skills. (3) An interactive cave exhibit involving a virtual reality research tour and 3-D stalagmite reconstructions will be built for the Sierra Nevada Recreation Corporation (owner of two of the Sierran caves targeted for study). The project would also include support for graduate education.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.

北美西南部 (SWNA) 是世界上气候最敏感的地区之一，其水文气候本质上是多变的。大量证据表明，在末次冰河周期和全新世期间，该地区的水文气候在亚十年到千年尺度上发生了反复的、大规模的变化，但驱动这种变化的机制仍然不确定。在过去的变化和未来气候变化的潜在程度的背景下，需要对水文气候对扰动的响应和潜在的驱动机制有深入的了解。该研究小组的目标是为来自加利福尼亚州内华达山脉中部和南部的四个石笋生成一组多代理方解石和流体包裹体记录，这些记录在亚十年到百年尺度上得到解决，这些石笋跨越了最后一次冰消期到全新世。 通过整合高精度铀-钍测年、洞穴监测、多石笋记录和地球系统建模（单强迫水同位素跟踪模拟），研究小组将（1）评估北太平洋风暴路径行为和由此产生的降水信号如何存档在石笋代理记录中，以及（2）应用这些知识来研究变化背景下降水响应的机制。 过去21,000年的环境强迫。 将新的内华达山脉记录与正在为加利福尼亚州沿海和北部开发的补充石笋记录相结合，将允许对影响西南北部风暴路径行为和降水模式的机制进行区域性广泛调查。与新的同位素支持的瞬态气候演化自 21-ka 模拟（iTraCE-21ka 模型）进行比较，将进一步深入了解美国西部气候对不同强迫的全球驱动因素和响应时间。 综合洞穴监测-石笋代理-水同位素建模方法可以提供（1）深入了解气候和喀斯特过程如何印记石笋代理记录，以及（2）对美国西部古降水如何响应不断变化的气候条件提供急需的定量限制。潜在的更广泛影响（B.I.）包括三项外展活动，以整合代表性不足的高中和大学。 本科生参与塞拉石笋项目并向公众分发研究结果。 (1) 一个由本科生组成的团队（n=8）将通过加州大学戴维斯分校（加利福尼亚州的 C3Climate Change）垂直整合项目（VIP）的开发，正式融入研究。 该计划由赫尔姆斯利慈善信托基金向 VIP 联盟（都柏林大学是参与的 16 所大学之一）提供的资助支持，将包括每周研讨会、同行指导以及洞穴监测部分的团队研究。 (2) 将为西班牙裔服务机构瓦卡维尔（加利福尼亚州）高中开发基于气候科学的课程。该课程将整合石笋研究的各个方面和批判性思维技能的目标发展。 (3) 将为内华达山脉休闲公司（两个旨在研究的 Sierra 洞穴的所有者）建造一个涉及虚拟现实研究之旅和 3D 石笋重建的互动洞穴展览。 该项目还将包括对研究生教育的支持。该奖项反映了 NSF 的法定使命，并通过使用基金会的智力价值和更广泛的影响审查标准进行评估，被认为值得支持。

项目成果

On the Remote Impacts of Mid‐Holocene Saharan Vegetation on South American Hydroclimate: A Modeling Intercomparison

• DOI: 10.1029/2022gl101974
• 发表时间: 2023-06
• 期刊: Geophysical Research Letters
• 影响因子: 5.2
• 作者: Shivangi Tiwari;R. Ramos;F. Pausata;A. Legrande;Michael Griffiths;Hugo Beltrami;I. Wainer;A. Vernal;D. Litchmore;D. Chandan;Richard Peltier;Clay R Tabor;W. Peltier

Speleothems of South American and Asian Monsoons Influenced by a Green Sahara

• DOI: 10.1029/2020gl089695
• 发表时间: 2020-11
• 期刊: Geophysical Research Letters
• 影响因子: 5.2
• 作者: C. Tabor;B. Otto‐Bliesner;Zhengyu Liu

A mechanistic understanding of oxygen isotopic changes in the Western United States at the Last Glacial Maximum

对末次盛冰期美国西部氧同位素变化的机制理解

• DOI: 10.1016/j.quascirev.2021.107255
• 发表时间: 2021
• 期刊: Quaternary Science Reviews
• 影响因子: 4
• 作者: Tabor, Clay;Lofverstrom, Marcus;Oster, Jessica;Wortham, Barbara;de Wet, Cameron;Montañez, Isabel;Rhoades, Alan;Zarzycki, Colin;He, Chengfei;Liu, Zhengyu
• 通讯作者: Liu, Zhengyu