相关实验视频
Updated: Jul 11, 2026

07:28
Evolution of Staircase Structures in Diffusive Convection
Published on: September 5, 2018
概括
高度的空海相互作用驱动深海循环. 来自Weddell-1冰站的测量揭示了控制冬季风暴期间上海热量和动量交换的关键过程.
科学领域:
- 海洋学 海洋学 海洋学
- 气候科学 气候科学
- 大气科学 大气科学
背景情况:
- 高度空气-海冰相互作用对于深海循环和气候系统通信至关重要.
- 了解近地交换过程 (热量,盐,动量) 对海洋气候建模至关重要.
- 西部韦德尔海是研究这些空气-海冰相互作用的关键区域.
研究的目的:
- 直接测量海洋上层的乱热流和雷诺兹应力.
- 在冬季条件下分析海洋边界层的动态.
- 为了验证海洋混合层过程的模型.
主要方法:
- 利用美国-俄罗斯冰站Weddell-1进行现场测量.
- 1992年在韦德尔海西部的一场风暴期间收集的数据.
- 分析了Ekman螺旋,热量流,温度梯度,的粘度和的长度尺度.
主要成果:
- 在速度和动荡应力中观察到形成良好的Ekman螺旋.
- 发现混合层热量流和温度梯度之间存在很高的相关性.
- 确定了类似的旋粘度和热扩散率 (约. 0.02 m2/s) 的时间.
- 在垂直速度光谱中确定了一个与峰值波长成比例的流长度尺度.
结论:
- 测量支持一个模型,其中的粘度与边界应力相成比例,除以科里奥利斯参数.
- 这些发现增强了对高度地区海洋边界层物理学的理解.
- 数据通过完善空气-海冰相互作用的参数化,有助于改进气候模型.
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