Development of a Laser Spectroscopy System for Analysis of 17Oexcess on Ice Cores

开发用于分析冰芯上 17O 过量的激光光谱系统

• 批准号: 1341360
• 负责人: Eric Steig
• 金额: $ 35.76万
• 依托单位: University of Washington
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2013
• 资助国家: 美国
• 起止时间: 2013-10-01 至 2017-01-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1341360&HistoricalAwards=false
• 关键词: Development; Laser; Spectroscopy; System; Analysis

Steig/1341360This award supports a two-year project to develop a method for rapid and precise measurements of the difference in 18O/16O and 17O/16O isotope ratios in water, referred to as the 17O-excess. Measurement of 17O-excess is a recent innovation in geochemistry, complementing traditional measurements of the ratios of hydrogen (D/H) and oxygen (18O/16O). Conventional measurements of 17O/16O are limited in number because of the time-consuming and laborious nature of the analyses, which involves the conversion of water to oxygen via fluorination, followed by high-precision mass spectrometry. This project will use a novel cavity ring-down spectroscopy (CRDS) system developed by a joint effort of the University of Washington and Picarro, Inc. (Santa Clara, CA), along with the Centre for Ice and Climate (Neils Bohr Institute, Copenhagen). The primary intellectual merit of the research is the improvement of the CRDS method for measurements of 17Oexcess of discrete samples of water, to obtain precision and accuracy competitive with conventional methods using mass spectrometry. This will be achieved by quantification of the effects of water vapor concentration variability and instrument memory, precise calibration of the instrument against standard waters, and improvements to the spectroscopic analyses. The CRDS system will also be coupled to continuous-flow systems for ice core analysis, in collaboration with the University of Colorado, Boulder. The goal is to have an operational system available for ice core processing associated with the next major U.S.-led ice core project at South Pole, in 2015-2017. The broader impacts of the research include the ability to measure 17O-excess in ambient atmospheric water vapor, which can be used to improve understanding of convection, moisture transport, and condensation. The instrument development work proposed here is relevant to research supported by several NSF-GEO programs, including Hydrology, Climate and Large Scale Dynamics, Paleoclimate, Atmosphere Chemistry, and both the Arctic and Antarctic Programs. This proposal will support a postdoctoral researcher.

Steig/1341360该奖项支持一个为期两年的项目，该项目旨在开发一种快速精确测量水中 18O/16O 和 17O/16O 同位素比率差异（称为 17O 过量）的方法。 17O 过量测量是地球化学领域的一项最新创新，补充了氢 (D/H) 和氧 (18O/16O) 比率的传统测量。 17O/16O 的常规测量数量有限，因为分析过程耗时且费力，其中涉及通过氟化将水转化为氧气，然后进行高精度质谱分析。 该项目将使用华盛顿大学和 Picarro, Inc.（加利福尼亚州圣克拉拉）以及冰与气候中心（尼尔斯玻尔研究所，哥本哈根）。 该研究的主要智力价值是改进了用于测量 17O 过量离散水样的 CRDS 方法，以获得与使用质谱的传统方法相媲美的精度和准确度。这将通过量化水蒸气浓度变化和仪器记忆的影响、根据标准水精确校准仪器以及改进光谱分析来实现。 CRDS 系统还将与科罗拉多大学博尔德分校合作，与连续流系统相结合，进行冰芯分析。目标是为 2015-2017 年美国主导的下一个南极冰芯项目提供一个可用于冰芯处理的操作系统。 该研究的更广泛影响包括测量环境大气水蒸气中 17O 过量的能力，这可用于增进对对流、水分输送和冷凝的了解。 这里提出的仪器开发工作与多个 NSF-GEO 项目支持的研究相关，包括水文学、气候和大尺度动力学、古气候、大气化学以及北极和南极项目。该提案将支持一名博士后研究员。