EAGER: A Comparison of Lacustrine Carbonate d18O and Organic Matter dD from Drought Sensitive Lakes in the Western United States

EAGER：美国西部干旱敏感湖泊中湖相碳酸盐 d18O 和有机物 dD 的比较

• 批准号: 1346947
• 负责人: Mark Abbott
• 金额: $ 6.51万
• 依托单位: University of Pittsburgh
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2013
• 资助国家: 美国
• 起止时间: 2013-08-15 至 2015-07-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1346947&HistoricalAwards=false
• 关键词: EAGER; Comparison; Lacustrine; Carbonate; d18O

Instrumental climate records indicate that drought patterns in western North America are sensitive to Pacific Ocean variability and to interactions between the El Niño Southern Oscillation, and the North American monsoon. A deeper understanding of the past behavior of these modes is needed to improve predictions of future drought and pluvial cycles. This proposed research would: 1) provide proof of concept for the use of delta-Deuterium records in lake systems where single phase carbonates are not available for delta-18 Oxygen analyses and 2) add to a growing a network of quantitative paleoclimate data sets that would add a critical spatial and temporal perspective to our understanding of aridity patterns in western North America and associated synoptic climate teleconnections.The proposed project will develop lake sediment organic matter del-D records from two closed-basin lakes at centennial scale from two drought-sensitive lakes in the western US for the last 2,000 years. The first, Castor Lake, is a well-studied system in Washington State that has been instrumented for a decade with lake level sensors, water temperature loggers, sediment traps, a weather station, and annual ground, lake and stream sampling for water chemistry and stable isotopes. A decadal scale record of oxygen isotopes has been published from Castor Lake, and offers an opportunity for comparison with Algal del-D. The second lake, Graham Lake, is also a drought-sensitive system located in New Mexico, a region of great interest for drought studies. The team has visited this system, verified that it meets the criteria for their proposed work and plans to recover a series of overlapping cores for this study.The broader impacts are that if this new del-D technique is successful in these lakes without single phase carbonates, the resulting network of paleodrought datasets from the western US would provide important new information on the timing, duration and magnitude of wet/dry cycles and combined with ongoing research, identify spatial patterns of aridity in North America during late Holocene.

仪器气候记录表明，北美西部的干旱模式对太平洋变化以及厄尔尼诺南方涛动和北美季风之间的相互作用很敏感，需要更深入地了解这些模式的过去行为，以改进对未来的预测。这项拟议的研究将：1）为在单相碳酸盐无法用于 delta-18 氧分析的湖泊系统中使用 delta-氘记录提供概念证明，2）添加到建立一个定量古气候数据集网络，这将为我们理解北美西部的干旱模式和相关的天气气候遥相关增加关键的时空视角。拟议的项目将从两个封闭的湖泊沉积物有机物 del-D 记录中开发湖泊沉积物有机物 del-D 记录。过去 2,000 年来美国西部两个干旱敏感湖泊的百年规模盆地湖泊 第一个是卡斯特湖，是华盛顿州的一个经过充分研究的系统，十年来一直在监测湖泊水位。传感器、水温记录仪、沉积物收集器、气象站以及每年对地面、湖泊和溪流进行水化学和稳定同位素采样。卡斯特湖已发布了十年尺度的氧同位素记录，并提供了与藻类进行比较的机会。 del-D. 第二个湖泊，格雷厄姆湖，也是位于新墨西哥州的一个干旱敏感系统，该地区是干旱研究的重点地区，该团队已经访问了该系统，并验证了其符合其拟议工作的标准。计划恢复一系列更广泛的影响是，如果这种新的 del-D 技术在这些没有单相碳酸盐的湖泊中取得成功，由此产生的美国西部古干旱数据集网络将提供有关时间、持续时间和强度的重要新信息湿/干循环并结合正在进行的研究，确定了全新世晚期北美干旱的空间模式。