Collaborative Research: Sensitivity of Walker circulation to CO2 forcing during the late Pliocene as an analogue for future climate change

合作研究：上新世晚期沃克环流对二氧化碳强迫的敏感性作为未来气候变化的类比

• 批准号: 2103015
• 负责人: Tripti Bhattacharya
• 金额: $ 20.09万
• 依托单位: Syracuse University
• 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: 2021-05-15 至 2025-04-30
• 项目状态: 未结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=2103015&HistoricalAwards=false
• 关键词: Collaborative; Research; Sensitivity; Walker; circulation

The proposed study will produce new measurements and simulations of the late-Pliocene (3.3 – 2.58 million years ago) to determine how the Pacific Walker Circulation responds to a warmer climate. The Pacific Walker Circulation is a key feature of the climate system; it impacts temperature and rainfall worldwide, with important socioeconomic consequences. The late Pliocene is an attractive target for understanding sensitivity of Pacific Walker Circulation to changes in atmospheric carbon dioxide concentrations because it features biome distributions, geography, and topography that are similar to the present-day. Carbon dioxide concentration decreased from roughly today’s level during the mid-Piacenzian (3.3 – 3.0 million years ago) to around the preindustrial level during the early-Pleistocene (2.58 million years ago), coincident with (and perhaps driving) the expansion of Northern Hemisphere ice sheets. The study will produce new geochemical data (sedimentary leaf wax isotope data from both western and eastern sides of the tropical Pacific) and will develop water isotopologue tracking enabled Earth System Model simulations to investigate Pacific Walker Circulation sensitivity to late-Pliocene changes in carbon dioxide concentrations and ice sheets. The products will contribute to the existing archives of Pliocene Earth System simulations and observations, providing a community resource for future research and education. A collection of educational activities at high school, undergraduate, and graduate level are also planned to train next generation climate scientists. Strengthening of the Pacific Walker Circulation in response to carbon dioxide increase is a common prediction from atmosphere-ocean coupled Earth System Models. Yet, confidence in this prediction is low due to the short duration of instrumental records, which only chronicle a narrow range of transient climate responses to carbon dioxide increase. This project aims to test model predictions of changes in Pacific Walker Circulation during the late-Pliocene with measurements of deuterium concentrations of sedimentary leaf wax from both western and eastern sides of the tropical Pacific. The team will develop a series of water isotopologue tracking enabled Earth System Model simulations and leaf wax records to understand 1) whether a weaker Pacific Walker Circulation existed during the mid-Piacenzian; 2) what is the sensitivity of Pacific Walker Circulation to carbon dioxide decline during the late-Pliocene; and 3) if the early-Pleistocene glacial expansion strengthened the Pacific Walker Circulation.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.

拟议的研究将对上新世晚期（3.3 - 258 万年前）进行新的测量和模拟，以确定太平洋沃克环流如何应对气候变暖。太平洋沃克环流是其影响的气候系统的一个关键特征；上新世晚期是了解太平洋沃克环流对大气二氧化碳浓度变化敏感性的一个有吸引力的目标，因为它具有与太平洋沃克环流相似的生物群落分布、地理和地形特征。现今的二氧化碳浓度从皮亚琴兹中期（3.3-300万年前）的大致今天水平下降到更新世早期（258万年前）的工业化前水平，与（可能是驱动）一致。该研究将产生新的地球化学数据（来自热带太平洋西侧和东侧的沉积叶蜡同位素数据）并将发展。水同位素追踪使地球系统模型能够模拟太平洋沃克环流对上新世晚期二氧化碳浓度和冰盖变化的敏感性。这些产品将有助于现有的上新世地球系统模拟和观测档案，为未来的研究提供社区资源。还计划在高中、本科生和研究生阶段开展一系列教育活动，以培训下一代气候科学家。加强太平洋沃克环流以应对二氧化碳增加是大气-海洋耦合地球系统的常见预测。然而，由于仪器记录持续时间短，该预测的可信度较低，仅记录了对二氧化碳增加的短暂气候反应。该项目旨在测试模型对太平洋沃克环流后期变化的预测。 - 上新世，测量热带太平洋西侧和东侧沉积叶蜡的氘浓度，该团队将开发一系列水同位素追踪技术，支持地球系统模型模拟和叶蜡记录，以了解 1) 太平洋沃克是否较弱。环流存在于皮亚新世中期；2）上新世晚期太平洋沃克环流对二氧化碳下降的敏感性如何；3）早更新世冰川扩张是否加强了太平洋沃克环流。该奖项反映了 NSF 的法定使命通过使用基金会的智力优点和更广泛的影响审查标准进行评估，并被认为值得支持。

项目成果

Biomarker Approaches for Reconstructing Terrestrial Environmental Change

重建陆地环境变化的生物标记方法

• DOI: 10.1146/annurev-earth-032320-095943
• 发表时间: 2022-05
• 期刊: Annual Review of Earth and Planetary Sciences
• 影响因子: 14.9
• 作者: Inglis, Gordon N.;Bhattacharya, Tripti;Hemingway, Jordon D.;Hollingsworth, Emily H.;Feakins, Sarah J.;Tierney, Jessica E.
• 通讯作者: Tierney, Jessica E.

Patterns and Mechanisms of Northeast Pacific Temperature Response to Pliocene Boundary Conditions

东北太平洋温度对上新世边界条件的响应模式和机制

• DOI: 10.1029/2021pa004370
• 发表时间: 2022-06
• 期刊: Paleoceanography and Paleoclimatology
• 影响因子: 3.5
• 作者: Brennan, Peter R.;Bhattacharya, Tripti;Feng, Ran;Tierney, Jessica E.;Jorgensen, Ellen M.
• 通讯作者: Jorgensen, Ellen M.

Expansion and Intensification of the North American Monsoon During the Pliocene

上新世北美季风的扩展和加强

• DOI: 10.1029/2022av000757
• 发表时间: 2022-12
• 期刊: AGU Advances
• 影响因子: 8.4
• 作者: Bhattacharya, Tripti;Feng, Ran;Tierney, Jessica E.;Rubbelke, Claire;Burls, Natalie;Knapp, Scott;Fu, Minmin
• 通讯作者: Fu, Minmin