Time-average and time-dependent parts of core flow

Physics of the Earth and Planetary Interiors

Volumn 155, Issue 1-2, 2006, Pages 120-139

  Amit, Hagay ^a   Olson, Peter ^a  

^a JOHNS HOPKINS UNIVERSITY   (United States)

Author keywords

Core flow; Geodynamo; Geomagnetic secular variation; Length of day variations; Mantle tomography; Thermal wind; Torsional oscillations

Indexed keywords

GEOMAGNETISM; OSCILLATIONS; TOMOGRAPHY; VORTEX FLOW;

CORE FLOW; GEODYNAMO; GEOMAGNETIC SECULAR VARIATION; LENGTH-OF-DAY VARIATIONS; MANTLE TOMOGRAPHY; THERMAL WIND; TORSIONAL OSCILLATIONS;

GEOPHYSICS;

CORE-MANTLE BOUNDARY; PALEOMAGNETISM; SECULAR VARIATION;

EID: 33644924322     PISSN: 00319201     EISSN: None     Source Type: Journal    
DOI: 10.1016/j.pepi.2005.10.006     Document Type: Article

References (63)

1. Amit, H., Olson, P., 2004. Helical core flow from geomagnetic secular variation. Phys. Earth Planet. Inter. 147, 1-25 doi:10.1016/ j.pepi.2004.02.006.
2. D.G. Andrews Atmospheric physics 2000 Cambridge University Press Cambridge, UK 229 pp
3. J. Aubert Steady zonal flows in spherical shell fluid dynamos J. Fluid Mech. 542 2005 53-67
4. J. Aurnou S. Andreadis L. Zhu P. Olson Experiments on convection in Earth's core tangent cylinder Earth Planet. Sci. Lett. 212 2003 119-134
5. G.E. Backus Kinematics of geomagnetic secular variation in a perfectly conducting core Philos. Trans. R. Soc. Lond. Ser. A 263 1968 239-266
6. G.E. Backus J.-L. LeMouël The region on the core mantle boundary where a geostrophic velocity field can be determined from frozen flux magnetic data Geophys. J. R. Astron. Soc. 85 1986 617-628
7. J. Bloxham Simple models of fluid flow at the core surface derived from geomagnetic field models Geophys. J. Int. 99 1989 173-182
8. J. Bloxham The steady part of the secular variation of the Earth's magnetic field J. Geophys. Res. 97 1992 19565-19579
9. J. Bloxham D. Gubbins Thermal core-mantle interactions Nature 325 1987 511-513
10. J. Bloxham A. Jackson Lateral temperature variations at the core-mantle boundary deduced from the magnetic field Geophys. Res. Lett. 17 1990 1997-2000
11. J. Bloxham A. Jackson Fluid flow near the surface of Earth's outer core Rev. Geophys. 29 1991 97-120
12. J. Bloxham S. Zatman M. Dumberry The origin of geomagnetic jerks Nature 420 2002 65-68
13. E.C. Bullard C. Freedman H. Gellman J. Nixon The westward drift of the Earth's magnetic field. Philos. Trans. R. Soc. Lond. Ser. A 243 1950 67-92
14. E.C. Bullard H. Gellman Homogeneous dynamos and terrestrial magnetism. Philos. Trans. R. Soc. Lond. Ser. A 247 1954 213-278
15. A. Chulliat G. Hulot Local computation of the geostrophic pressure at the top of the core Phys. Earth Planet. Inter. 117 2000 309-328
16. U.R. Christensen P. Olson Secular variation in numerical geodynamo models with lateral variations of boundary heat flow Phys. Earth Planet. Inter. 138 2003 39-54
17. R.G. Davis K.A. Whaler Determination of a steady velocity in a rotating frame of reference at the surface of the Earth's core Geophys. J. Int. 126 1996 92-100
18. A.M. Dziewonski D.L. Anderson Preliminary reference Earth model Phys. Earth Planet. Inter. 25 1981 297-356
19. T.M. Eubanks J.A. Steppe J.O. Dickey P.S. Callahan A spectral analysis of the Earth's angular momentum budget J. Geophys. Res. 90 1985 5385-5404
20. A.M. Forte J.X. Mitrovica Deep-mantle high-viscosity flow and thermochemical structure inferred from seismic and geodynamic data Nature 410 2001 1049-1056
21. C. Gire J.-L. LeMouël T. Madden Motions of the core surface derived by SV data Geophys. J. R. Astron. Soc. 84 1986 1-29
22. C. Gire J.-L. LeMouël Tangentially geostrophic flow at the core-mantle boundary compatible with the observed geomagnetic secular variation: The large-scale component of the flow Phys. Earth Planet. Inter. 59 1990 259-287
23. G. Glatzmaier R. Coe L. Hongre P. Roberts The role of the earth's mantle in controlling the frequency of geomagnetic reversals Nature 401 1999 885-890
24. D. Gubbins Finding core motions from magnetic observations. Philos. Trans. R. Soc. Lond. Ser. A 306 1982 249-256
25. D. Gubbins M. Richards Coupling of the core dynamo and mantle: Thermal or topographic? Geophys. Res. Lett. 13 1986 1521-1524
26. R. Hide Motions of the earth's core and mantle and variations of the main geomagnetic field Science 157 1967 55-56
27. R. Hide D.H. Boggs J.O. Dickey Angular momentum fluctuations within the Earth's liquid core and torsional oscillations of the core-mantle system Geophys. J. Int. 143 2000 777-786
28. R. Holme Electromagnetic core-mantle coupling-I. Explaining decadal changes in the length of day Geophys. J. Int. 132 1998 167-180
29. R. Holme K.A. Whaler Steady core flow in an azimuthally drifting reference frame Geophys. J. Int. 145 2001 560-569
30. J.R. Holton An introduction to dynamic meteorology 1992 Academic Press San Diego, US 511 pp
31. G. Hulot C. Eymin B. Langlais M. Mandea N. Olsen Small-scale structure of the geodynamo inferred from Oersted and Magsat satellite data Nature 416 2002 620-623
32. A. Jackson Time-dependency of tangentially geostrophic core surface motions Phys. Earth Planet. Inter. 103 1997 293-311
33. A. Jackson Intense equatorial flux spots on the surface of the Earth's core Nature 424 2003 760-763
34. A. Jackson J. Bloxham Mapping the fluid flow and shear near the core surface using the radial and horizontal components of the magnetic field Geophys. J. Int. 105 1991 199-212
35. Jackson, A., Bloxham, J., Gubbins, D., 1993. Time-dependent flow at the core surface and conservation of angular momentum in the coupled core-mantle system. In: LeMouël, J.-L., Smylie, D.E., Herring, T., (Eds.), Dynamics of Earth's Deep Interior and Earth Rotation, Geophysical Monograph 72 IUGG, vol. 12, pp. 97- 107.
36. A. Jackson A.R.T. Jonkers M.R. Walker Four centuries of geomagnetic secular variation from historical records Philos. Trans. R. Soc. Lond. Ser. A 358 2000 957-990
37. D. Jault C. Gire J.-L. LeMouël Westward drift, core motions and exchanges of angular momentum between core and mantle Nature 333 1988 353-356
38. D. Jault G. Hulot J.-L. LeMouël Mechanical core-mantle coupling and dynamo modeling Phys. Earth Planet. Inter. 98 1996 187-191
39. D. Jault J.-L. LeMouël The topographic torque associated with a tangentially geostrophic motion at the core surface and inferences on the flow inside the core Geophys. Astrophys. Fluid Dyn. 48 1989 273-296
40. D. Jault J.-L. LeMouël Physical properties at the top of the core and core surface motions Phys. Earth Planet. Inter. 68 1991 76-84
41. D. Jault J.-L. LeMouël Exchange of angular momentum between the core and the mantle J. Geomag. Geoelectr. 43 1991 111-129
42. S. Karato B.B. Karki Origin of lateral variation of seismic wave velocities and density in the deep mantle J. Geophys. Res. 106 2001 21771-21783
43. J.-L. LeMouël Outer core geostrophic flow and secular variation of Earth's magnetic field Nature 311 1984 734-735
44. X. Li B. Romanowicz Global mantle shear-velocity model developed using nonlinear asymptotic coupling theory J. Geophys. Res. 101 B10 1996 22245-22272
45. D. Lloyd D. Gubbins Toroidal fluid motion at the top of Earth's core Geophys. J. Int. 93 1990 521-526
46. D.E. Loper T. Lay The core-mantle boundary region J. Geophys. Res. 100 1995 6397-6420
47. G. Masters S. Johnson G. Laske H. Bolton A shear-velocity model of the mantle. Philos. Trans. R. Soc. Lond. Ser. A 354 1996 1385-1411
48. W.H. Munk G.J.F. Macdonald The Rotation of the Earth 1960 Cambridge University Press Cambridge, UK 323
49. P. Olson U.R. Christensen The time averaged magnetic field in numerical dynamos with nonuniform boundary heat flow Geophys. J. Int. 151 2002 809-823
50. P. Olson U.R. Christensen G.A. Glatzmaier Numerical modeling of the geodynamo: Mechanisms of field generation and equilibration J. Geophys. Res. 104 1999 10383-10404
51. A. Pais G. Hulot Length of day decade variations, torsional oscillations and inner core superrotation: Evidence from recovered core surface zonal flows Phys. Earth Planet. Inter. 118 2000 291-316
52. Pais, A., Oliveira, O., Nogueira, F., 2004. Nonuniqueness of inverted CMB flows and deviations from tangential geostrophy. J. Geophys. Res. 109 doi:10.1029/2004JB003012.
53. P.H. Roberts S. Scott On analysis of the secular variation J. Geomagn. Geoelectr. 17 1965 137-151
54. G. Schubert D. Turcotte P. Olson Mantle Convection in the Earth and Planets 2001 Cambridge University Press Cambridge, UK 940 pp
55. F. Stacey Physics of the Earth 1992 Brookfield Press Brisbane, Australia
56. F.R. Stephenson L.V. Morrison Long-term fluctuation in the Earth's rotation-700 B.C. to A.D. 1990 Philos. Trans. R. Soc. Lond. Ser. A 351 1995 165-202
57. J.B. Taylor The magneto-hydrodynamics of a rotating fluid and the earth's dynamo problem Proc. R. Soc. A 274 1963 274-283
58. Trampert, J., Deschamps, F., Resovsky, J., Yuen, D., 2004. Probabilistic tomography maps chemical heterogeneities throughout the lower mantle. Science 306, 853-856 doi:10.1126/science.1101996.
59. C.V. Voorhies Steady flows at the top of Earth's core derived from geomagnetic field models J. Geophys. Res. 91 1986 12444-12466
60. C.V. Voorhies G.E. Backus Steady flows at the top of the core from geomagnetic-filed models - the steady motions theorem Geophys. Astrophys. Fluid Dyn. 32 1985 163-173
61. K.A. Whaler Does the whole of Earth's core convect? Nature 287 1980 528-530
62. S. Zatman J. Bloxham Torsional oscillations and the magnetic field within the Earth's core Nature 388 1997 760-763
63. K. Zhang D. Gubbins On convection in the earth's core driven by lateral temperature variations in the lower mantle Geophys. J. Int. 108 1992 247-255