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arXiv · 2212.12820

Instantaneous Pole Velocity and Global Models

S. A. Ivanov·S. A. Merkuryev·I. M. Demina
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Abstract

A new approach to estimating the velocity of the pole moving is considered. The method uses the model-calculated spatial distribution of the (vector) horizontal component \textbf{H} for a given year and its change relative to the closest epochs. The velocity equation is obtained from the expression for the time dependence of the position of the pole $\mathbf{H}(λ(t),ϕ(t),t)=0$. Here $λ(t)$ and $ϕ(t)$ are the geographic coordinates of the pole at time $t$. The velocity between epochs can be found using the Hermite spline, which gives a smooth line that keeps the velocity vector in each epoch. We use IGRF and COV-OBSx2 models to find the horizontal component.

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S. A. Ivanov, S. A. Merkuryev, I. M. Demina. 2023-01-14. Instantaneous Pole Velocity and Global Models. https://arxiv.org/abs/2212.12820

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