Restratification of Mixed Layers

混合层的重新分层

• 批准号: 0326280
• 负责人: Michael Gregg
• 金额: --
• 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: 2003
• 资助国家: 美国
• 起止时间: 2003-09-01 至 2009-08-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0326280&HistoricalAwards=false
• 关键词: Restratification; Mixed; Layers

Traditional models and paradigms of the upper ocean vertical stratification rely on dynamics that take place in only the vertical dimension. Atmospheric forcing and turbulent processes create a "mixed layer" in the uppermost surface of the ocean. However, recent measurements in the North Pacific indicate that the water may have horizontal gradients of temperature and salinity and these may "slump" over. This project will conduct field work to examine the "slumping" process to determine how it plays a role in establishing the vertical stratification of the mixed layer. They will make measurements of temperature and salinity profiles at one location and will use the ship to sample a grid to capture three dimensional structures of temperature and salinity. Their goals are to observe the evolution of the slumping process and to obtain estimates of the forcing and dissipative terms which drive the slumping and to determine the horizontal length scales of the slumping which will give an indication of the physical processes that halt the slumping process. They will also investigate whether the size of the density contrasts depends on the larger-scale mean density gradient and this will determine whether the density contrasts can be predicted by combining combining one-dimensional dynamics and larger scale gradients. The datasets will be suitable for testing others' models of the three-dimensional mixed layer.

上层海洋垂直分层的传统模式和范例依赖于仅在垂直维度上发生的动态。大气强迫和湍流过程在海洋最上层表面形成了一个“混合层”。然而，最近在北太平洋的测量表明，海水可能有温度和盐度的水平梯度，这些梯度可能会“坍塌”。本项目将进行实地工作，检查“滑塌”过程，以确定它如何在建立混合层的垂直分层中发挥作用。他们将在一个地点测量温度和盐度分布，并将使用该船对网格进行采样，以捕获温度和盐度的三维结构。他们的目标是观察滑塌过程的演变，并获得驱动滑塌的强迫和耗散项的估计，并确定滑塌的水平长度尺度，这将表明停止滑塌过程的物理过程。他们还将研究密度对比的大小是否取决于较大尺度的平均密度梯度，这将确定是否可以通过结合一维动力学和较大尺度梯度来预测密度对比。 该数据集将适用于测试其他人的三维混合层模型。