A Salt Finger Tracer Release Experiment

盐指示踪剂释放实验

• 批准号: 0081502
• 负责人: Raymond Schmitt
• 金额: $ 215.6万
• 依托单位: Woods Hole Oceanographic Institution
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2000
• 资助国家: 美国
• 起止时间: 2000-09-01 至 2004-08-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0081502&HistoricalAwards=false
• 关键词: Salt; Finger; Tracer; Release; Experiment

0081502 SchmittAn extensive field experiment will be conducted in the area of the extensive thermohaline staircase in the western tropical Atlantic to investigate the role of double diffusion in subsurface water mass transformation. A purposeful tracer (Sulfur hexafluoride SF6) will be released into a layer near the middle of the staircase to obtain a robust 9-month measurement of vertical mixing and lateral dispersion. Surveys of fine- and microstructure with a profiling instrument will determine the dissipation rates of turbulent kinetic energy and thermal variance. Formulae for the relationship of these dissipation rates to vertical diffusivity depend dramatically on whether the source of energy for mixing is salt fingering or turbulence. This experiment will determine the relative contribution of these two sources to the vertical mixing of tracer, salt and heat. A moored CTD/Current profiler will be used to relate fine- and microstructure surveys to the long term tracer dispersion. The hope is that the work will lead to improved parameterizations of diapycnal mixing for general circulation and climate prediction models.

0081502 Schmitt 将在热带大西洋西部广泛的温盐阶梯区域进行广泛的现场实验，以研究双扩散在地下水团转化中的作用。一种有目的的示踪剂（六氟化硫 SF6）将被释放到楼梯中间附近的一层，以获得 9 个月的垂直混合和横向扩散的稳健测量结果。使用分析仪器对精细和微观结构进行测量将确定湍流动能和热方差的耗散率。这些耗散率与垂直扩散率之间关系的公式很大程度上取决于混合能量来源是盐指效应还是湍流。该实验将确定这两个来源对示踪剂、盐和热量的垂直混合的相对贡献。系泊 CTD/电流剖面仪将用于将精细和微观结构调查与长期示踪剂分散联系起来。希望这项工作能够改进大气环流和气候预测模型的二重混合参数化。