Data-driven detection of waves in Earth's core and geophysical interpretation

数据驱动的地核波探测和地球物理解释

基本信息

批准号：
2214244
负责人：
Bruce Buffett
金额：
$ 17.23万
依托单位：
University of California-Berkeley
依托单位国家：
美国
项目类别：
Standard Grant
财政年份：
2022
资助国家：
美国
起止时间：
2022-07-01 至 2024-06-30
项目状态：
已结题

来源：
https://www.nsf.gov/awardsearch/showAward?AWD_ID=2214244&HistoricalAwards=false
关键词：
Data driven detection waves Earth

项目摘要

Earth’s magnetic field is an important element of the Earth system because it contributes to the habitability of our planet. Its existence protects the surface environment from charged particles that stream from the Sun. However, the origins of the magnetic field lie deep inside the liquid metal core, where it is continually generated by turbulent fluid motions. Many aspects of this generation process are poorly understood. Vast quantities of data from recent satellite missions create new opportunities to probe the generation process. The goal of this project is to combine modern methods in Data Science with the recent satellite observations to detect waves in the liquid metal core. These waves contribute to time variations in the magnetic field and provide broader insights into the underlying dynamics. These insights inform our understanding of the generation process, which enables predictions of changes in the magnetic field (much like weather forecasts). The objective is to assess changes in the protection of our surface environment, which benefits society. The project also supports fundamental research into the Earth system and supports the education of underrepresented groups in STEM disciplines.Satellite observations have substantially improved the quality of information that can be recovered from the magnetic field. Reliable estimates for the second time-derivative (known as secular acceleration) have become feasible in the past few years, and these records are well suited for detecting waves at the top of the core. This study uses a method known as dynamic mode decomposition to extract waves from huge volumes of satellite data. Detection of waves, and the recovery of the wave speeds, provides unique information about conditions at the top of the core. Many of the candidate waves depend on stratification at the top of the core, so detection of waves can offer strong constraints on the strength of stratification. Ultimately these questions are related to the geological evolution of the core and Earth as a whole. Factors such as the vigor of mantle convection or the extent of chemical interactions contribute to conditions at the core-mantle boundary. While useful records of secular acceleration are necessarily restricted to the satellite era (last twenty years), the duration of observed fluctuations means that the available record is now sufficient to extract novel insights into the dynamics of our planet.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.

地球磁场是地球系统的重要元素，因为它有助于我们星球的可居住性。它的存在可保护地表环境免受从太阳流出的带电颗粒。但是，磁场的起源位于液态金属芯内，在液体金属芯中，它是由湍流运动不断产生的。这一代过程的许多方面对此很了解。来自最近的卫星任务的大量数据创造了新的机会来探究生成过程。该项目的目的是将数据科学中的现代方法与最近的卫星观测结果结合在一起，以检测液态金属芯中的波浪。这些波促进了磁场中的时间变化，并为基础动力学提供了广播公司的见解。这些见解介绍了我们对生成过程的理解，这可以预测磁场的变化（就像天气预报一样）。目的是评估保护我们的地表环境的变化，这使社会受益。该项目还支持对地球系统的基本研究，并支持STEM学科中代表性不足的群体的教育。卫生馆的观察结果显着提高了可以从磁场中回收的信息质量。在过去的几年中，对第二次衍生（称为世俗加速度）的可靠估计值已变得可行，并且这些记录非常适合检测核心顶部的波。这项研究使用一种称为动态模式分解的方法来从大量卫星数据中提取波。检测波和波速的恢复，提供了有关核心顶部条件的独特信息。许多候选波取决于核心顶部的分层，因此检测波可以对分层强度产生强大的限制。最终，这些问题与整个核心和地球的地质发展有关。诸如地幔对话的活力或化学相互作用程度等因素导致核心壳边界处的条件。虽然世俗加速的有用记录必须仅限于卫星时代（最近二十年），但观察到的波动的持续时间意味着现有记录现在足以提取对我们星球动态的新颖见解。该奖项反映了NSF的法规使命，并且通过评估值得通过基础知识的优点和广泛的效果来评估，这是NSF的法规任务，并且值得通过评估。