scholarly journals Long-term changes in solar quiet (Sq) geomagnetic variations related to Earth's magnetic field secular variation

2013 ◽  
Vol 118 (6) ◽  
pp. 3712-3718 ◽  
Author(s):  
Blas F. de Haro Barbas ◽  
Ana G. Elias ◽  
Ingrid Cnossen ◽  
Marta Zossi de Artigas
Keyword(s):  
Magnetic Field ◽  
Secular Variation ◽  
Earth’S Magnetic Field ◽  
Geomagnetic Variations ◽  
Long Term Changes ◽  
Earth's Magnetic Field

The westward drift of the Earth's magnetic field

1950 ◽  
Vol 243 (859) ◽  
pp. 67-92 ◽  
Keyword(s):  
Magnetic Field ◽  
Secular Variation ◽  
Outer Part ◽  
Earth’S Magnetic Field ◽  
Dynamo Theory ◽  
The Core ◽  
The Earth ◽  
Earth's Magnetic Field ◽  
Harmonic Analyses ◽  
Westward Drift

The westward drift of the non-dipole part of the earth’s magnetic field and of its secular variation is investigated for the period 1907-45 and the uncertainty of the results discussed. It is found that a real drift exists having an angular velocity which is independent of latitude. For the non-dipole field the rate of drift is 0.18 ± 0-015°/year, that for the secular variation is 0.32 ±0-067°/year. The results are confirmed by a study of harmonic analyses made between 1829 and 1945. The drift is explained as a consequence of the dynamo theory of the origin of the earth’s field. This theory required the outer part of the core to rotate less rapidly than the inner part. As a result of electromagnetic forces the solid mantle of the earth is coupled to the core as a whole, and the outer part of the core therefore travels westward relative to the mantle, carrying the minor features of the field with it.

Secular variation of the Earth's magnetic field revealed by Mexican Geomagnetic Repeat Stations during the last two centuries

2021 ◽  
pp. 103652
Author(s):  
Avto Goguitchaichvili ◽  
Esteban Hernández ◽  
Rafael García ◽  
Vadim Kravchinsky ◽  
Rubén Cejudo ◽  
...  
Keyword(s):  
Magnetic Field ◽  
Secular Variation ◽  
Earth’S Magnetic Field ◽  
Earth's Magnetic Field

scholarly journals Slow variations of the Earth’s magnetic field: technical, methodological and organizational features of measurements

2019 ◽  
Vol 127 ◽  
pp. 02026
Author(s):  
Sergey Y. Khomutov
Keyword(s):  
Magnetic Field ◽  
Global Network ◽  
Earth’S Magnetic Field ◽  
Measurement Systems ◽  
Long Term Stability ◽  
Earth's Magnetic Field ◽  
Methodological Problems ◽  
Organizational Features ◽  
Magnetic Observatories

Variations of the Earth’s magnetic field with times of several years or more reflect the processes within the planet and cause great scientific interest. Over the past 100 years the regular observations at magnetic observatories (MOs) and repeat stations are the only experimental basis for studying such variations. In recent decades, satellite measurements have complemented ground-based measurements, thus partially solving the problems of spatially highly heterogeneous global network of magnetic observatories. Absolute observations are made at MOs to get the total field intensity vector. Until now, these measurements are performed manually, they are labor intensity and subject to many factors, that are often poorly controlled and reduce the reliability of the results, especially over long periods of time (years and decades), including (1) systematic errors of used magnetometers; (2) magnetic pollution of the absolute pavilion and its surroundings (at a distance of the first hundred meters); (3) instability of the pillars and remote target required to determine magnetic declination; (4) changes of observers and their weak qualification. Significant methodological problems arise if MO is moved to new location without special activity or infrastructure of MO (pavilions or pillars) is changed without careful control. For long-term stability and reliability of measurements, magnetic observatories were joined in IAGA network and then INTERMAGNET. Within these networks, requirements and standards have been defined, absolute magnetometers are compared every two years and observers are being trained. Modern hardware technologies allow to solve partially problems the automation of absolute observations, the self-calibration of the magnetometers, the checking of the MO’s magnetic environment, etc. Fully automated measurement systems help to expand the MO network.

scholarly journals Drivers of Upper Atmosphere Climate Change

Eos ◽  
2020 ◽  
Vol 101 ◽  
Author(s):  
Sarah Stanley
Keyword(s):  
Climate Change ◽  
Magnetic Field ◽  
Carbon Dioxide ◽  
Upper Atmosphere ◽  
Earth’S Magnetic Field ◽  
Temperature Trends ◽  
Earth's Magnetic Field ◽  
New Research

New research confirms the influence of carbon dioxide on long-term temperature trends in the upper atmosphere, but changes in Earth’s magnetic field also play a key role.

scholarly journals Multipole Analysis. II. Geomagnetic Secular Variation

1969 ◽  
Vol 22 (4) ◽  
pp. 481 ◽  
Author(s):  
RW James
Keyword(s):  
Magnetic Field ◽  
Secular Variation ◽  
Time Trends ◽  
Earth’S Magnetic Field ◽  
Geomagnetic Secular Variation ◽  
Rates Of Change ◽  
Multipole Analysis ◽  
Earth's Magnetic Field

The method of multipole analysis described in Part I is applied to the Earth's magnetic field for various epochs between 1845 and 1965, allowing the geomagnetic secular variation to be illustrated by time trends in the multipole parameters. The rates of change of the multipole parameters are used to separate the secular variation into non.drifting, meridional drifting, and longitudinal drifting components, which are discussed in detail for the epoch 1965.

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