Collaborative Research: Ideas Lab: BLUES: Boundary Layer Under-ice Environmental Sensing

合作研究：创意实验室：BLUES：冰下边界层环境传感

• 批准号: 2322220
• 负责人: Alexander Forrest
• 金额: $ 35.29万
• 依托单位: University of California-Davis
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2023
• 资助国家: 美国
• 起止时间: 2023-10-01 至 2026-09-30
• 项目状态: 未结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=2322220&HistoricalAwards=false
• 关键词: Collaborative; Research; Ideas; Lab; BLUES

Global climate change is driving all forms of ice to melt from the Earth’s surface and contribute to global sea-level rise. While evidence of ice melt is worldwide, such as decreasing sea-ice extent, loss of ice shelves in polar regions and a reduction in annual lake-ice coverage, ice melt rates are poorly quantified, resulting from limited field data and relatively coarse measurements of ice thickness. Ice thickness measurements, made by propagating acoustic signals through the ice, decrease in resolution as a function of the attenuation properties and overall ice thickness. Novel acoustic metamaterials will be used in this Ideas Lab: Engineering Technologies to Advance Underwater Sciences (ETAUS) project to develop a transformative technology tool that can provide long-range, high-resolution measurements of ice thickness and provide a new mechanism to image the internal structure of the ice. These high-resolution observations will be used to refine global estimates of ice melt by looking at changes through time. Initial testing and development will be conducted in a laboratory setting before validation on natural lake ice that is variable in its acoustic signal attenuation properties. In every phase, the development and experimental demonstration will be guided by numerical modeling. This developed instrument will be transformative in terms of scientific understanding of all forms of ice within the cryosphere from the Arctic to the Antarctic. While polar regions are at the forefront of climate change, they are also some of the least accessible areas of the planet and make it difficult for the public to engage. To this end, new educational materials will be developed with the help of the education and outreach team at the Tahoe Environmental Research Center, which will be used to help broaden public participation in lake science and engineering.To effectively monitor and predict climate-related changes, a key scientific need in all disciplines of the under-ice scientific community is to accurately measure ice accretion and melt rates at the ice/water interface, then use that information to generate better models of under-ice water circulation and mixing. However, existing technologies are limited by their imaging capabilities, measurement resolutions, and bulky sizes, which hinder their applications for scientific discovery. To address these limitations, this project will develop a new metamaterial-enhanced acoustic phased array (MEAPA) system and to explore the application of this system for high-resolution estimations of ice melt. Graded index acoustic metamaterials will be investigated to provide improved focusing, beam steering, and collimation properties to achieve high-resolution imaging (subwavelength resolution) in thinner ice and to further enhance the detection range of the MEAPA system in thicker ice. The developed MEAPA system will be characterized and validated in laboratory and field settings. Then, it will be used to better parameterize bottom roughness, and the data will be coupled to boundary layer dynamics observations of lake ice in three-dimensional hydrodynamic models. Coupling the engineering development of this instrument with the scientific need of the polar ice community will inform subgrid processes of General Circulation Models (GCM) for polar regions. Ultimately, this system will enable us to better predict ice growth and melt with accurate models and to better quantify mass gain and loss from lake ice to ice shelves in Antarctica.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.

全球气候变化正在推动地球表面各种形式的冰融化，并导致全球海平面上升，而全球范围内都有冰融化的证据，例如海冰范围缩小、极地冰架消失和冰架减少。在每年的湖冰覆盖范围中，冰融化速率的量化很差，这是由于有限的现场数据和通过冰传播声信号进行的冰厚度测量相对粗略，分辨率随着衰减特性的变化而降低。和整体冰厚度。超材料将用于这个创意实验室：推进水下科学的工程技术 (ETAUS) 项目，以开发一种变革性的技术工具，可以提供远距离、高分辨率的冰厚度测量，并提供一种新的机制来成像水下科学的内部结构这些高分辨率观测将用于通过观察随时间的变化来完善冰融化的全球估计，初步测试和开发将在实验室环境中进行，然后对声信号衰减变化的天然湖冰进行验证。属性。在每个阶段，开发和实验演示将以数值模型为指导，这将在对从北极到南极冰冻圈内所有形式的冰的科学理解方面产生变革。这些地区也是地球上最难到达的地区，因此公众很难参与其中。为此，将在太浩环境研究中心的教育和外展团队的帮助下开发新的教育材料。将用于帮助扩大公众对湖泊科学的参与为了有效监测和预测与气候相关的变化，冰下科学界所有学科的一个关键科学需求是准确测量冰/水界面的冰积聚和融化速率，然后利用该信息生成更好的模型然而，现有技术受到成像能力、测量分辨率和体积庞大的限制，这阻碍了它们在科学发现中的应用。为了解决这些限制，该项目将开发一种新的超材料增强声学。相控阵 (MEAPA) 系统和探索该系统在冰融化高分辨率估计中的应用，将研究梯度折射率声学超材料，以提供改进的聚焦、光束转向和准直特性，以在更薄的冰中实现高分辨率成像（亚波长分辨率）并进一步研究。增强 MEAPA 系统在较厚冰层中的探测范围。开发的 MEAPA 系统将在实验室和现场设置中进行表征和验证，然后将其用于更好地参数化底部粗糙度，并将数据与边界层动力学耦合。将该仪器的工程开发与极地冰群的科学需求相结合，将为极地地区的大气环流模型（GCM）的子网格过程提供信息，最终，该系统将使我们能够通过准确的模型更好地预测冰的生长和融化，并更好地量化从湖冰到南极洲冰架的质量增加和损失。该奖项反映了 NSF 的法定使命，并通过使用基金会的智力价值和更广泛的影响审查进行评估，被认为值得支持标准。