CAREER: CLUMPMAP - Glacial Climate from Clumped Isotope Thermometry

作为一名科学家和教育家，PI的终身职业目标是（i）开发，校准和应用地球化学工具用于古气候，更好地了解可以叠加代理的成岩过程，（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）建立和维护领先的古气候计划。这个项目旨在通过一个创新的项目来进一步实现所有这些目标，该项目利用了她在地质学中最令人兴奋的新工具之一：“成团”同位素方面的经验。具体而言，该项目将（i）重建末次盛冰期的陆地气候（LGM; ~ 23，000 - 19，000年前）;（ii）努力教育、招募和留住地球科学的多样化人口。该项目建立在PI最近的工作基础上，并描述了一个名为CLUMPMAP的项目，该项目使用沉积档案来研究LGM环境变化，并促进生物多样性。地球科学从末次冰期到最近的温度变化已经被研究，以限制气候如何对相对良好的约束力作出反应，因此，末次冰期矿床的地质数据为气候模型提供了有价值的基准。在接下来的五年里，该团队将把聚集同位素测温法应用于碳酸盐岩，并研究LGM的古气候。这款功能强大的新型地质温度计采用了最新的气源质谱技术，并基于测量碳酸盐矿物中13 C和18 O键随温度变化的“结块”。温度估计还使我们能够解开长期存在的碳酸盐18 O/16 O（d18 O）特征的戈尔迪结，并分离出流体d18 O。重建将以类似于PI先前在已发表研究中所做的方式与气候模型模拟进行比较。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。从她最近的工作假设将进行测试，重点是对流层结构和行星尺度大气动力学的作用，在确定热带和季风气候的敏感性LGM强迫。这项工作的一个重要方面将是评估模式预测的气候状态的可靠性，这些气候状态与目前有很大的不同。支持PI扩大研究和教育的综合计划，将CLUMPMAP发展成为社区的努力和资源; 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，加强他们继续接受高等教育的资格; 3.为这些群体提供资源，以利用尖端技术进行研究; 4.吸引和培训早期职业科学家和学生参与外联活动; 5.通过提供榜样和指导，加强招聘和留住来自不同背景的优秀人才; 6.提高年轻人、他们的父母和他们的老师对地球科学的认识和欣赏; 7.建立更多能够而且应该改善目前在许多机构中代表性不足群体的文化的榜样; 8.在与改进气候模型有关的领域，进一步科学地了解深时（前全新世）地球系统; 9.通过实地考察和合作访问，与国际专家开展新的合作，促进美国学生和初级研究人员参与和培训研究;支持国家科学基金会和国家资助的分析设施，PI已经建成;和11。促进了该技术在沉积地质学和古气候学领域的推广。

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.