A two-step along-track spectral analysis for estimating the magnetic signals of magnetospheric ring current from Swarm data

作者：Martinec Zdenek^*; Velimsky Jakub; Haagmans Roger; Sachl Libor

来源：Geophysical Journal International, 2018, 212(2): 1201-1217.

DOI：10.1093/gji/ggx471

• Electromagnetic theory
• Geomagnetic induction
• Magnetic field variations through time
• Satellite magnetics

This study deals with the analysis of Swarm vector magnetic field measurements in order to estimate the magnetic field of magnetospheric ring current. For a single Swarm satellite, the magnetic measurements are processed by along-track spectral analysis on a track-by-track basis. The main and lithospheric magnetic fields are modelled by the CHAOS-6 field model and subtracted from the along-track Swarm magnetic data. The mid-latitude residual signal is then spectrally analysed and extrapolated to the polar regions. The resulting model of the magnetosphere (model MME) is compared to the existing Swarm Level 2 magnetospheric field model (MMA_SHA 2C). The differences of up to 10 nT are found on the nightsides Swarm data from 2014 April 8 to May 10, which are due to different processing schemes used to construct the two magnetospheric magnetic field models. The forward-simulated magnetospheric magnetic field generated by the external part of model MME then demonstrates the consistency of the separation of the Swarm along-track signal into the external and internal parts by the two-step along-track spectral analysis.

• 出版日期2018-2