We describe a new, original approach to the modelling of the Earth’s magnetic field. The overall objective of this study is to reliably render fast variations of the core field and its secular variation. This method combines a sequential modelling approach, a Kalman filter, and a correlation-based modelling step. Sources that most significantly contribute to the field measured at the surface of the Earth are modelled. Their separation is based on strong prior information on their spatial and temporal behaviours. We obtain a time series of model distributions which display behaviours similar to those of recent models based on more classic approaches, particularly at large temporal and spatial scales. Interesting new features and periodicities are visible in our models at smaller time and spatial scales. An important aspect of our method is to yield reliable error bars for all model parameters. These errors, however, are only as reliable as the description of the different sources and the prior information used are realistic. Finally, we used a slightly different version of our method to produce candidate models for the thirteenth edition of the International Geomagnetic Reference Field.

中文翻译：

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地核磁场的序列建模

我们描述了一种新的、原始的地球磁场建模方法。本研究的总体目标是可靠地呈现核心场及其长期变化的快速变化。该方法结合了顺序建模方法、卡尔曼滤波器和基于相关的建模步骤。对在地球表面测量的场贡献最显着的源进行建模。它们的分离基于关于它们的空间和时间行为的强先验信息。我们获得了一个模型分布的时间序列，这些分布显示的行为类似于基于更经典方法的最近模型的行为，特别是在大的时间和空间尺度上。在我们的模型中，在较小的时间和空间尺度上可以看到有趣的新特征和周期性。我们方法的一个重要方面是为所有模型参数生成可靠的误差线。然而，这些错误的可靠性取决于对不同来源的描述和所使用的先验信息是否真实。最后，我们使用了我们方法的一个稍微不同的版本来为第十三版国际地磁参考场生成候选模型。