Testing amino acid paleothermometry in radiocarbon-dated lake sediment

测试放射性碳测年湖泊沉积物中的氨基酸古温度测定法

• 批准号: 2317409
• 负责人: Darrell Kaufman
• 金额: $ 60.05万
• 依托单位: Northern Arizona University
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2023
• 资助国家: 美国
• 起止时间: 2023-08-15 至 2026-07-31
• 项目状态: 未结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=2317409&HistoricalAwards=false
• 关键词: Testing; amino; acid; paleothermometry; radiocarbon; Testing; amino; acid; paleothermometry; radiocarbon

Testing amino acid paleothermometry in radiocarbon-dated lake sedimentClimate change poses a major challenge for society. More information is needed to put recent climate changes into a long-term context of natural climate variability. This information helps to foresee possible future climate trends, especially those that involve slow-moving features of the climate system, which will continue to evolve over hundreds to thousands of years to come. A variety of geological evidence can be used to extend observations of temperature and other climate variables back in time. This project focuses on developing a new method of estimating temperature changes extending back thousands of years by using amino acids contained in lake sediment. The extent to which these molecules have been degraded depends largely on the temperature of the environment in which they have been stored and the length of time since they were formed. This project will use laboratory experiments to determine the temperature sensitivity of different degradation reactions coupled with radiocarbon dating to determine the age of the enclosing lake sediment. Funding will also be used to sustain the shared use of the Amino Acid Geochronology Laboratory at Northern Arizona University, which is the only one of its type in the United States. The project will also prepare undergraduate and graduate students for careers in the STEM workforce.Developing new methods to quantify past temperature is a high priority for climate science. The extent to which amino acids (AAs) in geologic settings have been chemically altered is primarily determined by the length of time elapsed since the molecules formed and by the ambient post-depositional temperature. Coupled with independent age control though radiocarbon (14C) dating, chemical reactions involving AAs can been used to quantify the timing and magnitude of past temperature changes. AAs are abundant in lake sediment, which has generally accumulated continuously in lakes over thousands of years, and thereby can be analyzed in detailed time series from widely distributed sites. This project will generate the first major AA dataset on 14C-dated and laboratory heated lake sediment. This project builds on a growing number of studies of AAs in lake sediment and it takes advantage of NSF-supported lake-core community resources. This award will sustain the Amino Acid Geochronology Laboratory as research infrastructure, enabling it to continue its long tradition of training users, offering pilot-study analyses, and assisting with data interpretation and curation. This project will also support STEM graduate and undergraduate students.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.

在放射性碳日期的湖泊沉积物变化中测试氨基酸的氨基酸热量法对社会构成了重大挑战。需要更多信息将最近的气候变化置于自然气候变化的长期背景下。这些信息有助于预见未来可能的气候趋势，尤其是那些涉及气候系统缓慢移动特征的信息，这些趋势将继续发展到未来数百到几千年。可以使用多种地质证据来扩展温度和其他气候变量的观察结果。该项目着重于开发一种新的方法，用于估计温度变化，通过使用湖泊沉积物中的氨基酸延长数千年。这些分子降解的程度在很大程度上取决于它们存储的环境的温度以及它们形成以来的时间长度。该项目将使用实验室实验来确定与放射性碳年代结合的不同降解反应的温度灵敏度，以确定封闭湖泊沉积物的年龄。资金还将用于维持亚利桑那大学北部氨基酸地球体学实验室的共同使用，这是美国唯一类型的一种。该项目还将为STEM劳动力的职业准备本科生和研究生准备。开发新的方法来量化过去的温度是气候科学的重点。化学改变了地质环境中的氨基酸（AA）的程度主要取决于由于形成分子和环境沉积后温度以来经过的时间长度。加上独立的年龄控制，尽管放射性碳（14C）的年代均可使用，涉及AA的化学反应可用于量化过去温度变化的时间和幅度。 AA在湖泊沉积物中很丰富，湖泊的沉积物通常在数千年的时间内连续积聚在湖泊中，从而可以在分布广泛的地点中以详细的时间序列进行分析。该项目将在14C和实验室加热的湖泊沉积物上生成第一个主要的AA数据集。该项目以越来越多的AAS在湖泊沉积物中的研究为基础，它利用了NSF支持的湖核心社区资源。该奖项将作为研究基础设施维持氨基酸地球体学实验室，使其能够继续培训用户的悠久传统，提供试验研究分析，并协助进行数据解释和策划。该项目还将支持STEM毕业生和本科生。该奖项反映了NSF的法定任务，并被认为是值得通过基金会的知识分子优点和更广泛影响的评论标准来评估值得支持的。