Measurements of Mixing and Stable Isotope Ratios of Atmospheric CH4 from Air Samples Collected from a Transect of Pacific Ocean Between Los Angeles and NZ

从洛杉矶和新西兰之间的太平洋横断面采集的空气样本中大气 CH4 的混合和稳定同位素比的测量

• 批准号: 9730818
• 负责人: Henry Ajie
• 金额: $ 5万
• 依托单位: University of California-Irvine
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 1998
• 资助国家: 美国
• 起止时间: 1998-08-01 至 1999-07-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=9730818&HistoricalAwards=false
• 关键词: Measurements; Mixing; Stable; Isotope; Ratios

This project was submitted for consideration under the NSF Program, "Career Advancement Awards for Minority Scientists and Engineers". The research consists of a series of atmospheric methane measurements that will provide a North-South Pacific Ocean transect distribution for methane abundance and stable carbon isotopic composition (13C and 12C). The main scientific objectives of the measurements are to determine the latitudinal mixing ratios of atmospheric methane in order to understand the dominant sources that might be contributing to its increasing global concentration levels. Surface clean air samples will be analyzed for 13C/12C, D/H and mixing ratios at different latitudes and longitudes from shipboard collections. The collections will be made from a transect of the Pacific Ocean between Los Angeles, CA and Auckland, New Zealand. The air samples (collected using pressurized cylinders) will be analyzed using GC/FID (methane concentration) and for 13C/12C and D/H abundances using a isotope ratio mass spectrometer (IRMS, Finnigan MAT). Data will be incorporated into an existing database for a global distribution of atmospheric methane abundance and isotopic composition. Overall, the study will help to develop global information on atmospheric methane that can be incorporated into models which assess the secular trends, source strengths, and influence of this important greenhouse on global climate.

该项目是在美国国家科学基金会“少数民族科学家和工程师职业进进奖”项目下提交的。该研究包括一系列大气甲烷测量，将提供南北太平洋甲烷丰度和稳定碳同位素组成（13C和12C）的样带分布。测量的主要科学目标是确定大气甲烷的纬向混合比率，以便了解可能导致其全球浓度水平上升的主要来源。将分析船上收集的不同纬度和经度的表面清洁空气样本的13C/12C， D/H和混合比。该系列将从洛杉矶，加州和奥克兰，新西兰之间的太平洋横断面制作。空气样本（使用加压气瓶收集）将使用GC/FID（甲烷浓度）进行分析，并使用同位素比质谱仪（IRMS, Finnigan MAT）进行13C/12C和D/H丰度分析。数据将被纳入现有的大气甲烷丰度和同位素组成全球分布数据库。总的来说，这项研究将有助于开发关于大气甲烷的全球信息，这些信息可被纳入评估这种重要温室气体对全球气候的长期趋势、来源强度和影响的模式。