Paleointensity extremes: Dynamic implications and future fields

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I propose to use my recently developed modeling techniques to resolve a fundamental disconnect between measurements of the strength of the ancient geomagnetic field (paleointensity) and theories of Earth's core dynamic and use this to answer outstanding questions about how fast Earth's magnetic field can change and how our protective barrier might change in the foreseeable future.Earth's magnetic field has been protecting our planet for at least 3.4 billion years and, despite being one on the oldest known features of Earth, there remain many aspects of how the field is generated and how it has evolved over time that are poorly understood. This makes is difficult to predict how the field will behave in the future. Currently, our best predications of future variations only extend about 5 years into the future. This is often too short to meet the needs of long terms investments, such as those required for space satellites and ground based power infrastructure, which rely on the shielding provided by the magnetic field.To predict future changes in the geomagnetic field we have to unravel past changes in the field and the physics that governs them. Understanding the evolution of the deep Earth and the physics behind extreme geomagnetic features, such as rapid field changes, are frontiers in paleomagnetic research that have implications for the predictability of our protective barriers future. However, our ability to understand these phenomena is held back by the uncertain reliability of the paleointensity data needed to understand these key features. To push these boundaries forward, we must ensure the fidelity of our observations, which requires a full understanding of the physical behavior that affects paleointensity data. This is especially important for time periods where the observed paleointensities contradict our most advanced understanding of how the magnetic field works.This project will use my newly developed tools to bridge the gap between specimen-level paleointensity data and global geomagnetic field reconstructions, and will take a radically different approach that utilizes "big data" analyses of millions of simulated and real results. Much like a surveyor would assess a building based on the quality of the materials and how they were used to construct the building, I will assess the building blocks of paleointensity data to determine the quality of the results.Armed with this new capability, I will provide a robust assessment of the validity of the Levantine archeomagnetic spikes, which record field intensity changes with rates tens faster than ever observed. Such extreme changes are beyond current dynamo theory and their resolution may have a profound impact on how we understand the dynamics of the outer core. Then, using a next generation geomagnetic field construction spanning the last 4,000 years, I will determine the longevity of the recent decline in dipole field strength and assess how long into the near future the current weakening of Earth's magnetic shield is likely to persist and how it will affect the modern world and the technologies that we all rely on in our daily lives.