Overview:

  • The Earth’s Magnetic Environment
  • ESA Swarm Mission
  • Secular variation: Jerks, IGRF and Model Updates
  • Modelling Uncertainties
  • Summary

Earth’s Magnetic Field:

  • Dominant core field varies over months to years (±60,000 nT)
  • Fields due to complex current systems in the ionosphere and magnetosphere vary from seconds to years (±60 nT)
  • Localised crustal field stable through time (±10 nT)
  • Now resolving ocean tides induced fields (±2 nT) Credit: GFZ,DTU 44th General Meeting September 22nd, 2016 Glasgow, Scotland, UK Wellbore Positioning Technical Section

Global Magnetic Field Modelling:

  • Spherical harmonic ‘degree’ of model represents spatial resolution
  • Produced annually since 1990s
  • A high temporal and spatial resolution
  • Most models describe time-varying main field and include crustal and some external fields
  • Accurately quantified errors (compared against ground measurements)

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View the entire Presentation:

Using Swarm Satellite Data to Improve Global Geomagnetic Reference Modeling 

 

Ciarán Beggan

 

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