As posted by the Working Group V of the International Association of Geomagnetism and Aeronomy (IAGA), the 13th generation of the International Geomagnetic Reference Field (IGRF) has been released at the end of 2019. Following IAGA recommendations, in this work we present a candidate model for the IGRF-13, for which we have used the available Swarm satellite and geomagnetic observatory ground data for the last year. In order to provide the IGRF-13 candidate, we have extrapolated the Gauss coefficients of the main field and its secular variation to January 1st, 2020. In addition, we have generated a Definitive Geomagnetic Reference Field model for 2015.0 using the same modelling approach, but focussed on a 1-year time window of data centred on 2015.0. To jointly model both satellite and ground data, we have followed the classical protocols and data filters applied in geomagnetic field modelling. Novelty arrives from the application of bootstrap analysis to solve issues related to the inhomogeneity of the spatial and temporal data distributions. This new approach allows the estimation of not only the Gauss coefficients, but also their uncertainties.

中文翻译：

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Bootstrapping Swarm 和天文台数据以生成 DGRF 和 IGRF-13 的候选者

正如国际地磁与大气学协会 (IAGA) 第五工作组发布的那样，第 13 代国际地磁参考场 (IGRF) 已于 2019 年底发布。 根据 IAGA 的建议，在这项工作中，我们提出了一个IGRF-13 的候选模型，我们使用了去年可用的 Swarm 卫星和地磁观测站地面数据。为了提供 IGRF-13 候选，我们将主磁场的高斯系数及其长期变化外推到 2020 年 1 月 1 日。此外，我们使用相同的建模方法生成了 2015.0 的最终地磁参考场模型，但专注于以 2015.0 为中心的 1 年时间窗口数据。为了联合模拟卫星和地面数据，我们遵循了地磁场建模中应用的经典协议和数据过滤器。新颖性来自自举分析的应用，以解决与空间和时间数据分布的不均匀性相关的问题。这种新方法不仅可以估计高斯系数，还可以估计它们的不确定性。