Quantifying Oceanic Whitecap Energy Dissipation and Bubble-Mediated Air-Sea Fluxes

量化海洋白浪能量耗散和气泡介导的海气通量

基本信息

批准号：
NE/T000309/1
负责人：
Adrian Callaghan
金额：
$ 72.57万
依托单位：
Imperial College London
依托单位国家：
英国
项目类别：
Research Grant
财政年份：
2019
资助国家：
英国
起止时间：
2019 至无数据
项目状态：
已结题

来源：
https://gtr.ukri.org/projects?ref=NE%2FT000309%2F1
关键词：
Quantifying Oceanic Whitecap Energy Dissipation

项目摘要

The winds constantly transfer energy from the atmosphere to the global oceans and seas helping to generate surface waves, currents and tearing water droplets directly from the crests of the steepest waves. The interaction of the wind and the surface ocean is an extremely complex process that still remains to be fully understood by ocean scientists and engineers and remains an active area of research. Perhaps the most fundamental consequence of wind blowing over the surface of the oceans is the generation of waves. Our ability to forecast the generation, evolution, and decay of ocean waves is important for the way humans interact with the global oceans. For example, wave forecasts are routinely used to help shipping companies plan the transport of goods and people across the global oceans, marine engineers need to know how often large waves occur and how these waves will interact with the structures they build for use in the ocean, oceanographers need to predict the how ocean waves affect weather and climate, and recreational sailors, swimmers and surfers rely on accurate wave forecasts to safely enjoy the seas and oceans around our coastline.Of particular interest to oceanographers is the energy balance between the wind and the waves. Since the wind acts as the primary source of energy for the waves, there must be a mechanism for dissipating this energy input, otherwise the waves would continue to grow. Part of this energy dissipation occurs along our coastlines where incoming waves break as they enter shallow water, releasing their energy. This release of energy helps to entrain air into the water, to move sediment and sand, and to create chaotic turbulent water motions. However, the vast majority of wave energy is dissipated by waves breaking in the open ocean. These are easy to spot on a windy day because of the bubbles and white foam they produce, commonly called whitecaps. The importance of these whitecaps to how the Earth's climate evolves is an area of huge interest to oceanographers, atmospheric scientists and climate scientists. Within each whitecap there are thousands of bubbles ranging in size from the width of a human hair to about the width of a 5 pence piece. These bubbles are like tiny replicas of the atmosphere that exchange gas with the surrounding water. This bubble-mediated mechanism of gas transfer is very important to how much carbon dioxide is transferred from the atmosphere to the ocean. When each of these bubbles rises to the water surface and bursts it can send tiny sea spray droplets into the atmosphere, much like the fizz of a glass of soda drink that you see when you look at it from the side. When these tiny droplets are in the atmosphere they can help to form clouds over the ocean, transport bacteria from the ocean surface into the atmosphere and can scatter light from the sun. Gaining a better understanding of how much these bubbles and sea spray droplets matter to the Earth's climate is important to make accurate future projections of the Earth's climate.To tackle these difficult questions, our research will use state of the art wave making facilities to replicate breaking ocean waves in the laboratory at Imperial College, and will photograph whitecaps in the Adriatic Sea where we have access to a unique ocean observing platform that is operated by the Italian Institute of Marine Science. We will use a combination of wave height gauges, digital cameras and stereovision image processing techniques, to measure wave energy, photograph the breaking wave foam, and count the number and measure the size of bubbles generated by the breaking waves. These data will be used to improve computer models of ocean waves, and predictions of the exchange of gas between the atmosphere and the oceans for use in computer models of Earth's climate.

风不断地将能量从大气中传递到全球海洋和海洋，有助于直接从最陡波的波峰中产生表面波，电流和撕裂水滴。风与地面海洋的相互作用是一个极其复杂的过程，海洋科学家和工程师仍然尚待充分理解，并且仍然是一个积极的研究领域。海洋表面吹风的最根本结果也许是波浪产生。我们预测海浪的一代，进化和衰变的能力对于人类与全球海洋互动的方式很重要。 For example, wave forecasts are routinely used to help shipping companies plan the transport of goods and people across the global oceans, marine engineers need to know how often large waves occur and how these waves will interact with the structures they build for use in the ocean, oceanographers need to predict the how ocean waves affect weather and climate, and recreational sailors, swimmers and surfers rely on accurate wave forecasts to safely enjoy the seas and oceans around our coastline.Of海洋学家特别感兴趣的是风与波浪之间的能量平衡。由于风充当波浪的主要能源，因此必须有一种耗散该能量输入的机制，否则波浪将继续增长。这种能量耗散的一部分发生在我们的海岸线沿着进入浅水时的海浪中断，从而释放了能量。这种能量的释放有助于将空气夹在水中，移动沉积物和沙子，并产生混乱的湍流水运动。但是，绝大多数波能通过在开阔的海洋中破裂的波消散。由于它们产生的气泡和白色泡沫，通常称为Whitecaps，因此在大风天很容易发现。这些白人对地球气候如何发展的重要性是海洋学家，大气科学家和气候科学家的巨大兴趣领域。在每个WhiteCap中，有成千上万个气泡的大小从人头发的宽度到大约5便士的宽度。这些气泡就像大气中的微小复制品，这些复制品与周围的水交换了气体。气泡介导的气体转移机制对于从大气中将二氧化碳转移到海洋中非常重要。当这些气泡中的每一个都升到水面并破裂时，它会使小海水液滴进入大气中，就像从侧面看时看到的一杯苏打饮料的泡沫一样。当这些小滴在大气中时，它们可以帮助在海洋上形成云，从海洋表面传输细菌进入大气，并可以从太阳中散射光。更好地了解这些气泡和海洋喷雾液滴对地球气候至关重要，对于对地球气候的准确预测至关重要。要解决这些困难的问题，我们的研究将利用艺术浪潮制造设施来复制帝国大学实验室中的破坏海浪，并将在Adripiatic Sea中拍摄我们的广告中，我们可以访问一项独特的海洋科学。我们将结合波高度计，数码相机和立体电视图像处理技术的组合，测量波浪能，拍摄断裂波泡沫，并计算断裂波产生的气泡的数量和测量。这些数据将用于改善海浪的计算机模型，并预测大气与海洋之间的气体交换，以在地球气候的计算机模型中使用。

项目成果

期刊论文数量（5）

专著数量（0）

科研奖励数量（0）

会议论文数量（0）

专利数量（0）

The influence of bandwidth on the energetics of intermediate to deep water laboratory breaking waves

DOI：
10.1017/jfm.2023.645
发表时间：
2023-09
期刊：
Journal of Fluid Mechanics
影响因子：
3.7
作者：
Rui Cao;E.M. Padilla;A. H. Callaghan
通讯作者：
Rui Cao;E.M. Padilla;A. H. Callaghan

Spatial Interpolation of Wave Fields Based on Limited Spatial Measurements

DOI：
10.1109/joe.2023.3274176
发表时间：
2023-10
期刊：
IEEE Journal of Oceanic Engineering
影响因子：
4.1
作者：
E. Padilla;Rui Cao;A. Callaghan
通讯作者：
E. Padilla;Rui Cao;A. Callaghan

The links between marine plastic litter and the air-sea flux of greenhouse gases

DOI：
10.3389/fmars.2023.1180761
发表时间：
2023-07
期刊：
Frontiers in Marine Science
影响因子：
3.7
作者：
L. Goddijn-Murphy;D. Woolf;R. Pereira;C. Marandino;A. Callaghan;J. Piskozub
通讯作者：
L. Goddijn-Murphy;D. Woolf;R. Pereira;C. Marandino;A. Callaghan;J. Piskozub

On the short-term response of entrained air bubbles in the upper ocean: a case study in the North Adriatic Sea

关于上层海洋夹带气泡的短期响应：北亚得里亚海的案例研究