Results 71 to 80 of about 323 (143)

A Statistical Study of the Properties of, and Geomagnetic Responses to, Large, Rapid Southward Turnings of the Interplanetary Magnetic Field

Journal of Geophysical Research: Space Physics, Volume 129, Issue 9, September 2024.
Abstract The interplanetary magnetic field (IMF) north‐south component, Bz, plays a crucial role in the interaction between the solar wind and the Earth's magnetosphere. We analyze 98 intervals in which Bz changed from >3 nT to <−3 nT in 5 min and for which these rapid southward turnings (STs) were surrounded by consistently northward or southward IMF.
Chiara Lazzeri, Andrey Samsonov, Colin Forsyth, Graziella Branduardi‐Raymont, Yulia V. Bogdanova   +4 more
wiley   +1 more source

An estimate of average lower mantle conductivity by wavelet analysis of geomagnetic jerks [PDF]

, 1999
WOS:000081900500014International audienceIt has recently been proposed that geomagnetic jerks observed at the Earth's surface could be viewed as singularities in the time behavior of the geomagnetic field with a regularity of about 1.5 when wavelet ...
Hulot, Gauthier, Dominique Gibert, Saracco, Ginette, Alexandrescu, Mioara Mandea, Mioara Mandea Alexandrescu, Le Mouël, Jean-Louis, Gibert, Dominique, Gauthier Hulot, Ginette Saracco, Alexandrescu, Mioara Mandea, Jean‐Louis Le Mouël, Lemouël, Jean-Loui   +11 more
core   +1 more source

Geomagnetic jerks: observation and theoretical modeling

, 2005
A geomagnetic jerk is a phenomenon involving the geomagnetic field secular variation when it abruptly changes its slope. It is generally accepted that it occurs on timescales from months to a few years and is of internal Earth origin.
De Michelis, P., Tozzi, R., Meloni, A.
core   +1 more source

Dynamic evolution of amplitude and position of geomagnetic secular acceleration pulses since 2000

Frontiers in Earth Science
Recent studies on the behavior of geomagnetic secular acceleration (SA) pulses have provided a basis for understanding the dynamic processes in the Earth’s core.
Chunhua Bai, Guoming Gao, Limin Wen, Guofa Kang   +3 more
doaj   +1 more source

On the Association of Substorm Identification Methods

Journal of Geophysical Research: Space Physics, Volume 129, Issue 9, September 2024.
Abstract Substorms are a rapid release of energy that is redistributed throughout the magnetosphere‐ionosphere system, resulting in many observable signals, such as enhancements in the aurora, energetic particle injections, and ground magnetic field perturbations.
C. J. Lao, C. Forsyth, M. P. Freeman, A. W. Smith, M. K. Mooney   +4 more
wiley   +1 more source

Using spectral analysis to detect singular events such as jerks in the geomagnetic field time series

, 2011
. In this study we have applied two spectral techniques in terms of Fourier and wavelet analysis to geomagnetic field time series and compared the results with those obtained from analogous analyses to synthetic data. Then, an algorithm has been proposed
E. Qamili, Mandea, M., A. De Santis, B. Duka, A. Isac, Qamili, E., M. Mandea, de Santis, A., Duka, B., Isac, A.   +9 more
core   +1 more source

The observational signature of modelled torsional waves and comparison to geomagnetic jerks [PDF]

, 2016
Torsional Alfven waves involve the interaction of zonal fluid flow and the ambient magnetic field in the core. Consequently, they perturb the background magnetic field and induce a secondary magnetic field.
Cox, GA, Mound, JE, Livermore, P.W., Cox, G.A., Livermore, PW, Mound, J.E.   +5 more
core   +1 more source

Geomagnetic jerks and rapid hydromagnetic waves focusing at Earth's core surface

, 2019
International audienceGeomagnetic jerks are abrupt changes in the second time derivative—the secular acceleration—of Earth’s magnetic field that punctuate ground observatory records.
Finlay, Christopher C., Finlay, Christopher,, Finlay, Christopher, C, Julien Aubert, Aubert, Julien, Christopher C. Finlay   +5 more
core   +1 more source

A core-surface flow model derived from magnetic data of Macau Science Satellite-1

Earth and Planetary Physics
The core-surface flow is crucial for understanding the dynamics of the Earth’s outer core and geomagnetic secular variations. Conventional core flow models often use a single set of spherical harmonic coefficients to represent the flow both inside and ...
JinFeng Li, YuFeng Lin, HongBo Yao, JuYuan Xu, Keke Zhang   +4 more
doaj   +1 more source

Dynamic Mode Decomposition of the Core Surface Flow Inverted From Geomagnetic Field Models

Geophysical Research Letters
Continuous satellite measurements of the Earth's magnetic field have advanced the characterization of spatial‐temporal variations of the main field over the past two decades.
Jinfeng Li, Yufeng Lin, Keke Zhang
doaj   +1 more source