Variability in water mass formation and ventilation rates in the southwestern Pacific Ocean based on Repeat Hydrography CFC measurements

基于重复水文学 CFC 测量的西南太平洋水团形成和通风率的变化

• 批准号: 0726517
• 负责人: Mark Warner
• 金额: $ 62.39万
• 依托单位: University of Washington
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2007
• 资助国家: 美国
• 起止时间: 2007-10-01 至 2013-09-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0726517&HistoricalAwards=false
• 关键词: Variability; water; mass; formation; ventilation

In this project, the US investigator will collaborate with Australian oceanographers to reoccupy two hydrographic sections that have been identified as essential by the U.S. CLIVAR/Carbon (CLImate VARiability and predictability) Repeat Hydrography Program. The dissolved chlorofluorocarbons (CFCs) on sections between Tasmania and Antarctica along 140'E in 2007-8 and along 170'W between 50'S and the equator in 2008-9 will be measured. This will be the fourth occupation of both these sections with chlorofluorocarbon tracers (CFC) and carbon system measurements since 1990. All three Chlorofluorocarbons: CFC-11, CFC-12, and CFC-113 will be measured on both sections, and SF6 will be measured on at least the pacific line. These tracer measurements complement the hydrographic observations that will include dissolved nutrients and carbon system parameters. The CFCs emphasize the contrast between newly-ventilated cold waters and the older, circumpolar waters of northern origin, and provide a "clock" to help understand observed changes in water mass properties in a circumpolar band located on the north side of the Antarctic Circumpolar Current, associated with the thick cold mixed layers where Subantarctic Mode Water and Antarctic Intermediate Water. These measurements will be interpreted in collaboration with the Australian colleagues. A variety of approaches to data analysis, including comparison with general circulation model output, will be utilized to interpret changes in the CFC concentrations and derived ages. Both numerical models and transit time distributions will be utilized to interpret the pCFC ages. Broader Impacts of Proposed WorkThis proposed research continues a long-term collaboration with Australian scientists, continues the training of a graduate student in model-data comparisons who will participate one of the expeditions, and provides data on changes in intermediate water formation rates and bottom waters that will help us better understand the role of the Southern Ocean in climate change and anthropogenic CO2 uptake. There is no seawater CFC measurement laboratory in the Australian oceanographic community. These CFC measurements make an important contribution to the interpretation of both the hydrographic and carbon system measurements of the Australian researchers. The Australian oceanographers have agreed to the data policy of the CLIVAR/Carbon Repeat Hydrography Program. These data from one of the regions of the ocean that is potentially important to studies of the ocean's response to changes in surface forcing will be publicly available soon after the voyages.

在该项目中，美国调查员将与澳大利亚海洋学家合作，重新占用美国CLIVAR/碳（气候变化可变性和可预测性）重复水文计划确定为必不可少的两个水文部分。2007- 2008年将测量塔斯马尼亚岛和南极洲之间沿着140 'E和沿着170' W 50'S和赤道之间的溶解氯氟烃（CFC）。这将是自1990年以来第四次对这两个部分进行氯氟烃示踪剂（CFC）和碳系统测量。所有三种氯氟烃：CFC-11，CFC-12和CFC-113将在两个部分进行测量，SF6将至少在太平洋线上进行测量。这些示踪测量补充了水文观测，水文观测将包括溶解营养物和碳系统参数。CFCs强调了新通风的冷沃茨和北方起源的较老的绕极沃茨之间的对比，并提供了一个“时钟”，以帮助了解在位于南极绕极流北侧的绕极带中观察到的水团性质的变化，该带与亚南极模式水和南极中层水的厚冷混合层有关。将与澳大利亚同事合作解释这些测量结果。将采用各种数据分析方法，包括与大气环流模式输出的比较，来解释氟氯化碳浓度和推算年龄的变化。数值模型和渡越时间分布将被用来解释pCFC年龄。这项拟议的研究将继续与澳大利亚科学家进行长期合作，继续培训一名将参加其中一次考察的研究生进行模型数据比较，并提供关于中层水形成率和底层沃茨变化的数据，这将有助于我们更好地了解南大洋在气候变化和人为CO2吸收中的作用。澳大利亚海洋学界没有海水氟氯化碳测量实验室。这些氟氯化碳测量结果为澳大利亚研究人员解释水文和碳系统测量结果做出了重要贡献。澳大利亚海洋学家已同意气候变化和大气分析/碳重复水文方案的数据政策。这些数据来自海洋的一个区域，对研究海洋对表面强迫变化的反应可能很重要，这些数据将在航行后不久公开。