Collaborative Research: Measuring abyssal warming with seismic Scholte waves

合作研究：用地震 Scholte 波测量深海变暖

• 批准号: 2241663
• 负责人: Wenbo Wu
• 金额: $ 47.54万
• 依托单位: Woods Hole Oceanographic Institution
• 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: 2023-05-15 至 2026-04-30
• 项目状态: 未结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=2241663&HistoricalAwards=false
• 关键词: Collaborative; Research; Measuring; abyssal; warming

Due to its large heat capacity, the ocean absorbs most of the excess energy trapped by anthropogenic greenhouse gases and thus regulates the rate of global warming. Accurate measurements of the ocean's warming are critical for understanding Earth's energy imbalance and climate anomalies. This project will employ a novel method of using seismic Scholte waves excited by repeating natural submarine earthquakes to monitor the global large-scale abyssal ocean warming. Preliminary results demonstrate the feasibility of the method, which will be expanded to the global ocean. Existing seismic data can be used to track abyssal oceawn warming back to the 1990s. The results will complement hydrographic measurements and improve understanding of the dynamics of the response of the abyssal ocean to surface forcing.This work will provide new observational constraints on abyssal ocean warming over the past few decades. The investigators will systematically search for shallow submarine repeating earthquakes since the 1980s. Scholte waves excited by these repeating events travel along the seafloor, and their propagation speed is sensitive to abyssal temperatures. Scholte wave travel time changes between repeating events thus constrain abyssal temperature change. The sensitivity of Scholte wave travel times to abyssal temperatures will be calculated using numerical simulations of wave propagation. Sensitivity kernels will be used to interpret the measured travel time changes, to infer average abyssal ocean warming along the waves' path, and to quantify uncertainties. The inferred warming will be compared against hydrographic and Argo data where available. Providing direct estimates of basin-scale abyssal ocean warming.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.

由于其巨大的热容量，海洋吸收了人为温室气体捕获的大部分多余能量，从而调节了全球变暖的速度。准确测量海洋变暖对于了解地球的能量不平衡和气候异常至关重要。该项目将采用一种新颖的方法，利用重复自然海底地震激发的地震肖尔特波来监测全球大规模深海变暖。初步结果证明了该方法的可行性，并将扩展到全球海洋。现有的地震数据可用于追踪 20 世纪 90 年代的深海变暖情况。这些结果将补充水文学测量，并增进对深海海洋对表面强迫响应动力学的理解。这项工作将为过去几十年的深海变暖提供新的观测限制。研究人员将系统地搜寻自 20 世纪 80 年代以来浅海海底重复发生的地震。由这些重复事件激发的肖尔特波沿着海底传播，其传播速度对深海温度敏感。斯科尔特波传播时间在重复事件之间发生变化，从而限制了深海温度的变化。肖尔特波传播时间对深海温度的敏感性将使用波传播的数值模拟来计算。灵敏度内核将用于解释测量的传播时间变化，推断沿波浪路径的平均深海变暖，并量化不确定性。推断的变暖将与可用的水文和 Argo 数据进行比较。提供对盆地规模的深海变暖的直接估计。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标准进行评估，被认为值得支持。