Detecting and Inverting Magnetic Waves for the Structure and Dynamics of Earth&#39;s Core

GSTDTAP

项目编号	1915807
	Detecting and Inverting Magnetic Waves for the Structure and Dynamics of Earth's Core
	Bruce Buffett (Principal Investigator)
主持机构	University of California-Berkeley
项目开始年	2019
	2019-06-01
项目结束日期	2022-05-31
资助机构	US-NSF
项目类别	Standard Grant
项目经费	237292(USD)
国家	美国
语种	英语
英文摘要	Fluctuations in the Earth's internal magnetic field are known to occur over a broad range of time scales. Magnetic reversals are detected in the geological record at irregular intervals of roughly several hundred thousand years, whereas modern ground-based observations reveal abrupt changes in the magnetic field over just a few years. Higher fidelity records from recent satellite missions now suggest that the abrupt changes in the magnetic field occur more frequently than previously believed. These events affect our ability to forecast the magnetic field, yet the origin of these disturbances is poorly understood. One viable interpretation involves waves at the top of the core. The investigators have found several types of waves that account for the periods and spatial patterns of the magnetic disturbance. The goal of this research is to detect these waves in geomagnetic observations and to recover estimates for the wave propagation speeds. This information will enhance our ability to forecast the magnetic field, and it will also provide unique insights into the physical state of the Earth's core, which will improve our understanding of how the magnetic field is generated by convection in the core. The project will support the research of a Hispanic graduate student at the University of California, Berkeley. This student will be introduced to advanced data analysis and computational methods, as well as parallel computing and scientific visualization. The investigators propose to use observations from the SWARM satellite to identify the origin of rapid geomagnetic fluctuations in the equatorial region of the Earth's core. They hypothesize that these fluctuations are a result of waves at the top of the core, and plan to adopt several types of wave models to interpret the geomagnetic signals. The investigators intend to use the wave models to extract information about the physical conditions that prevail near the core-mantle boundary, including the possible presence of stable stratification. They also seek to characterize the source mechanism for the waves because it connects the wave amplitudes to convective processes deeper in the core. The researchers also plan to search for evidence of topography on the core-mantle boundary using high-fidelity records of time variations in the geomagnetic field. Recovery of information about the topography on the core-mantle boundary would offer unexpected constraints on the style of convection in the lowermost mantle. 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.
文献类型	项目
条目标识符	http://119.78.100.173/C666/handle/2XK7JSWQ/213690
专题	环境与发展全球科技态势
推荐引用方式 GB/T 7714	Bruce Buffett .Detecting and Inverting Magnetic Waves for the Structure and Dynamics of Earth's Core.2019.