Maurits Metman

Maurits Metman

Profile

I am a PhD student in geophysics, as part of the Leeds-York NERC Doctoral Training Partnership (http://www.nercdtp.leeds.ac.uk/). At Leeds, I am a member of the Deep Earth Research Group, and I collaborate also with the Geomagnetism team at the British Geological Survey. My research revolves around the geomagnetic field, how it changes with time, and how we can use it to constrain the dynamics inside the Earth's core.

Memberships/Fellowships

  • Member of the American Geophysical Union (2018-)
  • Fellow of the Royal Astronomical Society (2016-)

Awards

  • IPGP Foreign Student Award, Congrès des Doctorants (2017)
  • Outstanding Student Poster Award, European Geosciences Union (2015)

Invited talks

  • American Geophysical Union Fall Meeting, Washington D.C. (2018)
  • British Geological Survey, Edinburgh (2018)
  • British Geological Survey, Edinburgh (2017)

Service

I am an active reviewer for the scientific journals:

  • Frontiers in Earth Science
  • Geophysical Journal International

Publications

  • Metman M. C., Livermore P. W. and Mound J. E. (2017). The reversed and normal flux contributions to axial dipole decay for 1880-2015. Physics of Earth and Planetary Interiors, 276: 106-117.

Selected conference contributions

  • Metman M. C., Livermore P. W., Mound J. E., and C. D. Beggan (2018). A purely diffusive model for geomagnetic secular variation. SEDI 16th Symposium (poster).
  • Metman M. C., Livermore P. W. and Mound J. E. (2017). The reversed and normal flux contributions to axial dipole decay for 1880-2015. IPGP Congrès des Doctorants (oral).
  • Metman M. C., Livermore P. W. and Mound J. E. (2016). Predicting the evolution of the SAA by characterisation and modelling of reversed flux patches. EGU General Assembly (poster).
  • Metman M. C., de Groot L. V., Thieulot C., Biggin A. J. and Spakman W. (2015). The sensitivity of geomagnetic reversal frequency to core-mantle boundary heat flux magnitude and heterogeneity. EGU General Assembly (poster).

Research interests

Specific research interests include:

  • The case of purely diffusive secular variation: for field evolution on yearly to decadal time scales (secular variation), it is widely accepted to ignore the effects of magnetic diffusion (the frozen-flux approximation). Unfortunately, this approximation on relies on poorly constrained properties of the core, therefore diffusion remains potentially important for short term SV. As such, I consider the secular variation end-member of pure diffusion without fluid flow, and ascertain if it can actually explain field evolution over the past decades.
  • Time-dependence of reversed flux patches: there exist several magnetic field patches on the core-mantle boundary characterised by a sign orientenation opposite to the field's axial dipole component (i.e. reversed flux patches). I study how the time-dependence of these patches explains the decay of the axial dipole over the past centuries.
  • Secular variation forecasts: by combining the effects of core fluid flow and magnetic diffusion on secular variations, I aim to improve field forecasts of the magnetic field that rely on fluid flow only.
  • Geomagnetic reversals and core-mantle heat flow: the geomagnetic field has reversed its polarity numerous times during Earth's lifetime, and the frequency of these reversals has been linked to the heat transfer through the core-mantle boundary. As such, I have studied to what extent we can constrain the time-dependence of this heat exchange with numerical dynamo simulations and the observed reversal frequencies for the past 300 million years.

Qualifications

  • MSc Geophysics (Cum Laude), Utrecht University
  • BSc Earth Sciences, Utrecht University

Research groups and institutes

  • Deep Earth
  • Institute of Geophysics and Tectonics