CAREER: CLUMPMAP - Glacial Climate from Clumped Isotope Thermometry

职业：CLUMPMAP - 来自簇同位素测温的冰川气候

• 批准号: 1352212
• 负责人: Aradhna Tripati
• 金额: $ 60.6万
• 依托单位: University of California-Los Angeles
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2014
• 资助国家: 美国
• 起止时间: 2014-04-01 至 2020-03-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1352212&HistoricalAwards=false
• 关键词: CAREER; CLUMPMAP; Glacial; Climate; Clumped

As a scientist and educator, the PI's lifelong career goals are to (i) develop, calibrate, and apply geochemical tools for use in paleoclimate, and better understand the diagenetic processes that can overprint proxies, (ii) improve public awareness of climate change, and the basic and social relevance of the geosciences, (iii) enhance diversity in the geosciences, and (iv) establish and maintain a leading paleoclimate program. This project seeks to further all of these objectives with an innovative program that capitalizes on her experience with one of the most exciting new tools in geology: "clumped" isotopes. Specifically the project will (i) reconstruct terrestrial climates during the Last Glacial Maximum (LGM; ~23,000-19,000 years ago), and (ii) work to educate, recruit, and retain a diverse population to the geosciences.Intellectual Merit: The project builds on the PI's recent work and describes a program termed CLUMPMAP that uses sedimentary archives to study LGM environmental change and promotes diversity in the geosciences. Changes in temperature from the LGM to recent have been studied to constrain how climate can respond to relative well-constrained forcings and as a result geologic data from LGM deposits provides valuable benchmarks for climate models. Over the next five years, the team will apply clumped isotope thermometry to carbonates and study LGM paleoclimate. This powerful new geothermometer uses the latest technology in gas-source mass spectrometry and is based on measuring the temperature-dependent 'clumping of 13C and 18O bonds in carbonate minerals. Temperature estimates also allow us to unravel the longstanding Gordian knot of carbonate 18O/16O (d18O) signatures and isolate fluid d18O. Reconstructions will be compared to climate model simulations in a manner analogous to what the PI has previously done in published studies. Thus results will provide insights into past climate variations and the processes driving them, and will be used to test the accuracy of physical representations of climate in models. Hypotheses from her recent work will be tested, focusing on role of tropospheric structure and planetary-scale atmospheric dynamics in determining the sensitivity of tropical and monsoonal climates to LGM forcings. An important aspect of this work will be assessing the reliability of model predictions of climate states that are substantially different than present.Broader impacts include: 1. Supporting the PI in expanding an integrated program of research and education, developing CLUMPMAP into a community effort and resource; 2. furthering the training and educational/career development of student and early career scientists from under-represented groups, strengthening their qualifications to continue on in higher education; 3. providing these groups with resources to conduct research with a cutting-edge technique; 4. engaging and training early career scientists and students in outreach; 5. enhancing the recruitment and retention of bright people from diverse backgrounds through the provision of role models and mentorship; 6. advancing knowledge and appreciation of geosciences amongst young people, their parents, and their teachers; 7. establishing more role models that can and should improve the present culture for under-represented groups in many institutions; 8. furthering scientific understanding of deep-time (pre-Holocene) Earth systems in areas that are relevant to improving climate models; 9. developing new collaborations with international experts and promoting the engagement and training of U.S. students and junior researchers in research, through fieldwork and collaborative visits; 10. support of a NSF- and state-funded analytical facility the PI has built; and 11. facilitating the dissemination of this technique in the fields of sedimentary geology and paleoclimate.

作为一名科学家和教育家，PI 的终身职业目标是 (i) 开发、校准和应用用于古气候的地球化学工具，并更好地了解可以套印代理的成岩过程，(ii) 提高公众对气候变化的认识，以及地球科学的基本和社会相关性，(iii) 增强地球科学的多样性，以及 (iv) 建立和维持领先的古气候计划。该项目旨在通过一项创新计划进一步实现所有这些目标，该计划利用了她在地质学中最令人兴奋的新工具之一“聚集”同位素方面的经验。具体来说，该项目将 (i) 重建末次盛冰期（LGM；约 23,000-19,000 年前）期间的陆地气候，以及 (ii) 致力于教育、招募和留住地球科学领域的多样化人群。 智力优势：该项目以 PI 最近的工作为基础，描述了一个名为 CLUMPMAP 的项目，该项目利用沉积档案来研究末次盛冰期环境变化并促进地球科学的多样性。人们对末次盛冰期到最近的温度变化进行了研究，以限制气候如何响应相对良好的强迫，因此来自末次盛冰期沉积物的地质数据为气候模型提供了有价值的基准。在接下来的五年中，该团队将应用团块同位素测温法来研究碳酸盐并研究末次盛世古气候。这款功能强大的新型地温计采用最新的气源质谱技术，基于测量碳酸盐矿物中随温度变化的 13C 和 18O 键聚集。温度估计还使我们能够解开碳酸盐 18O/16O (d18O) 特征的长期难题并分离流体 d18O。重建结果将与气候模型模拟进行比较，其方式与 PI 之前在已发表的研究中所做的类似。因此，结果将提供对过去气候变化及其驱动过程的见解，并将用于测试模型中气候物理表示的准确性。她最近工作中的假设将得到测试，重点是对流层结构和行星尺度大气动力学在确定热带和季风气候对末次盛宴强迫的敏感性方面的作用。这项工作的一个重要方面将是评估与目前有很大不同的气候状态模型预测的可靠性。更广泛的影响包括： 1. 支持 PI 扩展研究和教育综合计划，将 CLUMPMAP 发展为社区努力，并资源； 2. 促进来自代表性不足群体的学生和早期职业科学家的培训和教育/职业发展，提高他们继续接受高等教育的资格； 3. 为这些团体提供利用尖端技术进行研究的资源； 4. 吸引和培训早期职业科学家和学生进行外展活动； 5. 通过提供榜样和指导，加强招聘和留住来自不同背景的聪明人； 6. 提高年轻人、他们的父母和老师对地球科学的认识和欣赏； 7. 建立更多的榜样，能够而且应该改善许多机构中代表性不足群体的现有文化； 8. 在与改进气候模型相关的领域加深对深层（全新世前）地球系统的科学理解； 9. 通过实地考察和合作访问，与国际专家开展新的合作，并促进美国学生和初级研究人员参与和培训研究； 10. 支持 PI 建立的 NSF 和国家资助的分析设施； 11. 促进该技术在沉积地质学和古气候领域的传播。