一个世俗的变化候选人IGRF-14基于核心流逆转通过一个合奏卡尔曼光滑器
Kyle Gwirtz1,2, Terence Sabaka2, Weijia Kuang2
1University of Maryland, Baltimore County, Baltimore, USA.
概括
地球磁场的新世俗变化 (SV) 模型使用数据同化 (DA) 与集成卡尔曼光滑器 (EnKS) 进行改进的预测. 这种方法可以准确预测磁场变化,并揭示核心流结构.
科学领域:
- 地质物理学 地质物理学
- 地球科学 地球科学 地球科学
- 计算科学 计算科学
背景情况:
- 准确预测地球磁场的世俗变化 (SV) 对导航和基础设施至关重要.
- 现有的数据同化 (DA) 系统通常依赖于复杂的模型,可能无法完全捕捉核心动态.
研究的目的:
- 开发和验证2025.0-2030.0.0的候选平均世俗变化 (SV) 模型.
- 评估集成卡尔曼光滑器 (EnKS) 与地磁预测的冷流核心模型集成的有效性.
- 探索EnKS在不需要模型附加的前提下,在理解地力发电机的潜力.
主要方法:
- 一个数据同化 (DA) 系统采用冷流核心模型和集成卡尔曼波器 (EnKF) 与集成卡尔曼光滑器 (EnKS).
- 从卡尔马格场模型中对高斯系数进行同化,以估计核心流量.
- 根据推断的核心流量预测磁场变化的预测.
主要成果:
- 与仅使用EnKF的方法相比,EnKS增强的DA系统产生了优异的SV预测.
- 推断的核心流出了与已建立的模型相一致的结构,例如古怪的旋转和向西漂移.
- EnKS的方法在预测过去5年期间的平均VS方面被证明是有效的.
结论:
- 拟议的SV模型和EnKS方法提供了一个有希望的地磁预测进步.
- EnKS系统可以很容易地实现到现有的EnKF框架中,从而增强其预测能力.
- 这种方法为研究地球动力发电机提供了有价值的工具,特别是复杂的3D动力发电机模型.
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