Toroidal flux oscillation as possible cause of geomagnetic excursions and reversals

F.H. Busse, R.D. Simitev

Research output: Contribution to journalLetter

Abstract

It is proposed that convection driven dynamos operating in planetary cores could be oscillatory even when the oscillations are not directly noticeable from the outside. Examples of dynamo simulations are pointed out that exhibit oscillations in the structure of the azimuthally averaged toroidal magnetic flux while the mean poloidal field shows only variations in its amplitude. In the case of the geomagnetic field, global excursions may be associated with these oscillations. Long period dynamo simulations indicate that the oscillations may cause reversals once in a while. No special attempt has been made to use most realistic parameter values. Nevertheless some similarities between the simulations and the paleomagnetic record can be pointed out. Crown
Original languageEnglish
Pages (from-to)237-243
Number of pages7
JournalPhysics of the Earth and Planetary Interiors
Volume168
Issue number3-4
DOIs
Publication statusPublished - Jul 2008

Fingerprint

oscillation
oscillations
causes
planetary cores
core (planetary)
simulation
rotating generators
geomagnetism
geomagnetic field
magnetic flux
convection

Bibliographical note

© 2009, Elsevier. Licensed under the Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International http://creativecommons.org/licenses/by-nc-nd/4.0/

Keywords

  • geodynamo
  • excursions
  • reversal
  • dynamo oscillations

Cite this

@article{749fb12fe76b4dbea9f7283d661ff9fd,
title = "Toroidal flux oscillation as possible cause of geomagnetic excursions and reversals",
abstract = "It is proposed that convection driven dynamos operating in planetary cores could be oscillatory even when the oscillations are not directly noticeable from the outside. Examples of dynamo simulations are pointed out that exhibit oscillations in the structure of the azimuthally averaged toroidal magnetic flux while the mean poloidal field shows only variations in its amplitude. In the case of the geomagnetic field, global excursions may be associated with these oscillations. Long period dynamo simulations indicate that the oscillations may cause reversals once in a while. No special attempt has been made to use most realistic parameter values. Nevertheless some similarities between the simulations and the paleomagnetic record can be pointed out. Crown",
keywords = "geodynamo, excursions, reversal, dynamo oscillations",
author = "F.H. Busse and R.D. Simitev",
note = "{\circledC} 2009, Elsevier. Licensed under the Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International http://creativecommons.org/licenses/by-nc-nd/4.0/",
year = "2008",
month = "7",
doi = "10.1016/j.pepi.2008.06.007",
language = "English",
volume = "168",
pages = "237--243",
journal = "Physics of the Earth and Planetary Interiors",
issn = "0031-9201",
publisher = "Elsevier",
number = "3-4",

}

Toroidal flux oscillation as possible cause of geomagnetic excursions and reversals. / Busse, F.H.; Simitev, R.D.

In: Physics of the Earth and Planetary Interiors, Vol. 168, No. 3-4, 07.2008, p. 237-243.

Research output: Contribution to journalLetter

TY - JOUR

T1 - Toroidal flux oscillation as possible cause of geomagnetic excursions and reversals

AU - Busse, F.H.

AU - Simitev, R.D.

N1 - © 2009, Elsevier. Licensed under the Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International http://creativecommons.org/licenses/by-nc-nd/4.0/

PY - 2008/7

Y1 - 2008/7

N2 - It is proposed that convection driven dynamos operating in planetary cores could be oscillatory even when the oscillations are not directly noticeable from the outside. Examples of dynamo simulations are pointed out that exhibit oscillations in the structure of the azimuthally averaged toroidal magnetic flux while the mean poloidal field shows only variations in its amplitude. In the case of the geomagnetic field, global excursions may be associated with these oscillations. Long period dynamo simulations indicate that the oscillations may cause reversals once in a while. No special attempt has been made to use most realistic parameter values. Nevertheless some similarities between the simulations and the paleomagnetic record can be pointed out. Crown

AB - It is proposed that convection driven dynamos operating in planetary cores could be oscillatory even when the oscillations are not directly noticeable from the outside. Examples of dynamo simulations are pointed out that exhibit oscillations in the structure of the azimuthally averaged toroidal magnetic flux while the mean poloidal field shows only variations in its amplitude. In the case of the geomagnetic field, global excursions may be associated with these oscillations. Long period dynamo simulations indicate that the oscillations may cause reversals once in a while. No special attempt has been made to use most realistic parameter values. Nevertheless some similarities between the simulations and the paleomagnetic record can be pointed out. Crown

KW - geodynamo

KW - excursions

KW - reversal

KW - dynamo oscillations

UR - http://www.scopus.com/inward/record.url?scp=49749109099&partnerID=8YFLogxK

U2 - 10.1016/j.pepi.2008.06.007

DO - 10.1016/j.pepi.2008.06.007

M3 - Letter

AN - SCOPUS:49749109099

VL - 168

SP - 237

EP - 243

JO - Physics of the Earth and Planetary Interiors

JF - Physics of the Earth and Planetary Interiors

SN - 0031-9201

IS - 3-4

ER -