Ocean mixing and internal waves

海洋混合和内波

• 批准号: 140128-2009
• 负责人: Kelley, Daniel
• 金额: $ 1.6万
• 依托单位: Dalhousie University
• 依托单位国家: 加拿大
• 项目类别: Discovery Grants Program - Individual
• 财政年份: 2009
• 资助国家: 加拿大
• 起止时间: 2009-01-01 至 2010-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=422392
• 关键词: Ocean; mixing; internal; waves

Over the past several decades, Oceanographers have created numerical models of the ocean, akin to weather models. As with weather models, improvements have come along as computing power has increased, making it possible to simulate a wider fraction of the observed ocean phenomena. For example, the first ocean models were too coarse to resolve the approximately ten-kilometre scale ocean eddies, but it is now becoming possible to do this, at least for short-term predictions. Unfortunately, there are important ocean phenomena that are too small to be handled by any imaginable computer. A case in point is ocean mixing, which occurs on centimetre scales, far below the 10-kilometre limit of today's models. Ocean measurements reveal that this mixing occurs in complicated patterns, and sensitivity tests with models indicate that small variations in those patterns create large changes in the overall state of the ocean. That leaves Oceanographers in a bind. The only solution seems to be to parameterize the mixing, i.e. to approximate its affects using only the large-scale properties that the models can handle directly. My work centres on creating such parameterizations of various ocean mixing phenomena. The focus over the next several years will be mixing caused by high-frequency internal waves in coastal waters. Funded by NSERC and CFCAS, my group has amassed a particularly detailed set of observations of the phenomenon. The hope is to use this along with small-scale numerical simulations to develop more reliable parameterizations of this mode of mixing.

在过去的几十年里，海洋学家创建了类似于天气模型的海洋数值模型。 与天气模型一样，随着计算能力的提高，模型也得到了改进，使得模拟更广泛的观测到的海洋现象成为可能。 例如，第一个海洋模型太粗糙，无法解析大约十公里规模的海洋涡流，但现在已经可以做到这一点，至少对于短期预测而言。 不幸的是，有一些重要的海洋现象太小，无法用任何可以想象的计算机来处理。 一个典型的例子是海洋混合，它发生在厘米尺度上，远低于当今模型的 10 公里极限。 海洋测量表明，这种混合以复杂的模式发生，模型的敏感性测试表明，这些模式的微小变化会导致海洋整体状态的巨大变化。 这让海洋学家陷入了困境。 唯一的解决方案似乎是对混合进行参数化，即仅使用模型可以直接处理的大规模属性来近似其影响。 我的工作重点是创建各种海洋混合现象的参数化。 未来几年的焦点将是沿海水域高频内波引起的混合。 在 NSERC 和 CFCAS 的资助下，我的小组对这一现象收集了一套特别详细的观察结果。 希望将其与小规模数值模拟一起使用，以开发这种混合模式的更可靠的参数化。