Collaborative Research: Using a Combined Basin Analysis, Isotopic, and Modeling Approach to Reconstruct the LGM through Early Holocene Hydroclimate for Glacial Lake Mojave.

水是加州最重要和最不可预测的资源。作为一个以农业为主的经济体，CA的社会经济成功和可持续性与水的可用性密切相关。作为美国最大的州经济体，加州的健康对美国的健康至关重要。为了了解现代和未来的水资源可用性，科学家们回顾过去，为未来提供信息-这一研究领域称为古气候学。像莫哈韦沙漠这样的干旱环境对水的可用性特别敏感。因此，干旱环境是研究水循环过去变化的绝佳场所。该项目将重点关注银湖（CA）和联合收割机地质，水文和建模方法，以检查幅度，幅度和频率的变化，在水的可用性在一个最新的地质和气候动态的时期在地球的历史-从最后一次冰期最大期（约2000年）。距今24,000年至全新世早期（距今8,000年）。最重要的是，我们新颖的跨学科方法将使我们能够量化过去水资源的变化，并评估导致这些变化的气候驱动因素。 加州富勒顿和圣地亚哥峡谷学院（都是西班牙裔服务机构）将与布朗大学（一个主要的研究活跃的大学）合作，创造一个多样化的教育和研究经验，共15资助的学生和1博士后。这种多机构合作为2年制大学生转入4年制大学提供了一条明确的途径，并在代表性不足的群体中建立了积极的科学身份和归属感。本研究将使用组合盆地分析（即，核心到海岸），同位素和建模方法，以重建最小湖泊深度，最小湖泊体积和必要的水文气候条件的定量记录，在晚冰期到早全新世必要的填充银湖盆地，冰川湖莫哈韦的表面终端盆地。现有的和新的海滩或近岸地貌的网站将被确定和特点，使用无人机为基础，结构从运动摄影测量。这些海岸数据及其各自的年龄，将与测年和分析的沉积物岩心相结合，以量化最小湖泊深度的变化，从而湖泊体积，从24-8万年。结合这些地质数据，项目团队将应用湖泊系统的氧同位素约束、非稳态水文模型，量化晚冰期至全新世早期填充和维持银湖所需的必要条件。最后，这项工作的结果将进行比较，以评估在南部大盆地水文气候变化的主要驱动因素的各种气候强迫。 该奖项由地球科学部和大气和地球空间科学部通过古气候展望项目共同资助，并提高了各种机构类型的研究能力，能力和基础设施，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。

Water is California’s (CA) most critical and unpredictable resource. As a predominantly agricultural economy, CA’s socioeconomic success and sustainability are closely tied to water availability. And as the United States' largest state economy, the health of CA is important to the health of the United States. To understand modern and future water availability, scientists look to the past to inform the future – a field of study called paleoclimatology. Arid environments like the Mojave Desert are especially sensitive to water availability. As a result, arid environments are excellent sites for studying past changes in the water cycle. This project will focus on Silver Lake (CA) and combine geological, hydrological, and modeling methods to examine the amplitude, magnitude, and frequency of changes in water availability across one of the most geologically recent and climatically dynamic periods in Earth’s history – the period from the Last Glacial Maximum (ca. 24,000 years before present) to the early Holocene (8,000 years before present). Most importantly, our novel and transdisciplinary methods will allow us to quantify past changes in water availability and assess the climatic drivers that cause these changes. Cal-State Fullerton and Santiago Canyon College (both Hispanic Serving Institutions) will partner with Brown University (a major research-active university) to create a diverse educational and research experience for a total of 15 funded students and 1 post-doc. This multi-institutional collaboration provides a clear pathway for 2-year college students to transfer into 4-year universities and establishes a positive science identity and a sense of belonging in underrepresented groups. This research will use a combined basin analysis (i.e.,core-to-shore), isotopic, and modeling approach to reconstruct a quantitative record of minimum lake depth, minimum lake volume, and the requisite hydroclimatic conditions during the Late Glacial to Early Holocene necessary to fill the Silver Lake Basin, the ostensible terminal basin of Glacial Lake Mojave. Existing and new beach or near-shore geomorphic sites will be identified and characterized using UAV-based, Structure-from-Motion photogrammetry. These shore data, and their respective ages, will be coupled with dated and analyzed sediment cores to quantify changes in minimum lake depth, and thus lake volume, from 24-8 ka. Coupled with these geological data, the project team will apply oxygen isotopic constrained, non-steady state hydrologic models of the lake system to quantify the requisite conditions necessary to fill and sustain Silver Lake during the Late Glacial to Early Holocene. Finally, the results from this work will be compared to a variety of climatic forcings to evaluate the primary drivers of hydroclimatic change in the southern Great Basin. This award is co-funded by the Division of Earth Sciences and Division of Atmospheric and Geospace Sciences by way of the Paleo Perspectives on Present and Projected Climate program, and increases research capabilities, capacity and infrastructure at a wide variety of institution types, as outlined in the GEO EMBRACE DCL.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.