Physical interpretation and mathematical simulation of ionospheric precursors of earthquakes at midlatitudes

Zolotov, O. V.; Namgaladze, A. A.; Zakharenkova, Irina; Martynenko, O. V.; Шагимуратов, И. И.

doi:10.1134/s0016793212030152

Cited by 38 publications

(24 citation statements)

References 24 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…In the frame of the electromagnetic mechanism of LAI coupling there are a few attempts to model TEC disturbances' formation at ionospheric altitudes using 3‐D ionosphere models [e.g., Namgaladze et al , ; Liu et al , ; Klimenko et al , ; Zolotov et al , ]. The seismic influence in those studies is imposed as ionosphere lower boundary conditions (at 60–80 km altitude) for electric currents or fields.…”

Section: Rationalementioning

confidence: 99%

“…• Kuo et al (2014) reported an improved model of LAI coupling • Their formulation for ground-to-ionosphere region of the Earth is equivalent of Ohm's law with homogeneous conductivity • Therefore, Kuo et al (2014) formulation seems not to describe correctly electric currents, flowing between the Earth and ionosphere 10.1002/2016JA023441 Liu et al, 2011;Klimenko et al, 2011;Zolotov et al, 2012]. The seismic influence in those studies is imposed as ionosphere lower boundary conditions (at 60-80 km altitude) for electric currents or fields.…”

Section: Key Pointsmentioning

confidence: 99%

See 1 more Smart Citation

Comment on “An improved coupling model for the lithosphere‐atmosphere‐ionosphere system” by Kuo et al. [2014]

Prokhorov

Zolotov

2017

JGR Space Physics

Self Cite

View full text Add to dashboard Cite

The lithosphere‐atmosphere‐ionosphere coupling problem is a challenge nowadays. It requires understanding of (a) the physical mechanism that is responsible for plasma disturbances generation at ionospheric heights, (b) the penetration of seismogenic impact from the ground into the ionosphere through the underlying neutral atmosphere, and (c) on‐the‐ground (in‐the‐ground) sources generation. Kuo et al. (2014) reported an improved model of lithosphere‐atmosphere‐ionosphere coupling that includes the ionosphere as well as the underlying neutral atmosphere (from the ground up to the ionosphere altitudes, i.e., 60–80 km above the Earth's surface). The main feature of the Kuo et al. (2014) approach is that they find ground‐to‐ionosphere currents from ∇·trueJ→=0, trueJ→≡−∇ψ system of equations. In contrast to Kuo et al. (2011), where well‐known ∇·trueJ→=0,trueJ→=trueσ̂trueE→,trueE→=−∇ϕ equations are used, Kuo et al. (2014) looks better as it does not require the knowledge of electric conductivity σ profile. In this paper we show that the Kuo et al. (2014) equations can be obtained as a special case of the Kuo et al. (2011) ones, given the electric conductivity tensor is a spatially invariant scalar. Therefore, Kuo et al. (2014) formulation may not describe correctly electric currents flowing between the Earth and the ionosphere.

show abstract

Section: Rationalementioning

confidence: 99%

Section: Key Pointsmentioning

confidence: 99%

Comment on “An improved coupling model for the lithosphere‐atmosphere‐ionosphere system” by Kuo et al. [2014]

Prokhorov

Zolotov

2017

JGR Space Physics

Self Cite

View full text Add to dashboard Cite

show abstract

“…In order to explain these precursors, such as atmospheric conductivity anomalies and ionospheric TEC variations before strong earthquakes, one needs comprehensive coupling models for the lithosphere‐atmosphere‐ionosphere (LAI) coupling. Several LAI coupling models have been proposed, which include (1) radon ionization and charged aresol and change of load resistance in the global electric circuit [ Pulinets et al ., ; Pulinets and Legen ' ka , ; Pulinets et al ., ; Pulinets and Boyarchuk , ; Pulinets et al ., ; Pulinets , ; Pulinets and Ouzounov , ], (2) a stressed rock‐atmosphere–ionosphere coupling model [ Kuo et al ., ] based on experimental evidence of stressed rock currents [ Freund , ; Freund , ; Freund , , ], and (3) ionosphere dynamics with imposed zonal (west‐east) electric field [ Zolotov et al ., ; Namgaladze et al ., ; Zolotov et al ., ].…”

Section: Introductionmentioning

confidence: 99%

An improved coupling model for the lithosphere‐atmosphere‐ionosphere system

2014

View full text Add to dashboard Cite

In our previous model for the lithosphere-atmosphere-ionosphere coupling, the background magnetic field was assumed to be perpendicular to the horizontal plane. In the present paper, we improve the calculation of currents in the atmosphere by solving the current density J directly from the current continuity equation ∇ • J = 0. The currents in the atmosphere can be solved for any arbitrary angle of magnetic field, i.e., any magnetic latitude. In addition, a large ratio (~10) of Hall to Pedersen conductivities is used to generate a large Hall electric field. The effects of atmospheric currents and electric fields on the ionosphere with lithosphere current source located at magnetic latitudes of 7.5°, 15°, 22.5°, and 30°are obtained. For upward (downward) atmospheric currents flowing into the ionosphere, the simulation results show that the westward (eastward) electric fields dominate. At magnetic latitude of 7.5°or 15°, the upward (downward) current causes the increase (decrease) of total electron content (TEC) near the source region, while the upward (downward) current causes the decrease (increase) of TEC at magnetic latitude of 22.5°or 30°. The dynamo current density required to generate the same amount of TEC variation in the improved model is found to be smaller by a factor of 30 as compared to that obtained in our earlier paper. We also calculate the ionosphere dynamics with imposed zonal westward and eastward electric field based on SAMI3 code. It is found that the eastward (westward) electric field may trigger one (two) plasma bubble(s) in the nighttime ionosphere.

show abstract

“…When we investigate electromagnetic emissions induced by an electrical current or a magnetic moment on the surface or beneath the Earth, the effect of the medium air, crustal as well as ionosphere should be taken into account since these three media consist of different conductivities and we need to consider a lithosphereatmosphere-ionosphere electromagnetic coupling (Cummer, 2000). Several tentative LAIC models have been constructed based on ground-based and ionospheric observations prior to strong earthquakes and the investigation of the influence of external electrical field on ionospheric parameters has been developed quickly (Pulinets and Ouzounov, 2011;Pulinets and Davidenko, 2014;Hayakawa, 2013, 2014;Kuo et al, 2011Kuo et al, , 2014Zolotov et al, 2012;Zolotov, 2015). At the same time, the ionosphere plays an important role in electromagnetic propagation at ELF and very low frequency (VLF).…”

Section: Introductionmentioning

confidence: 99%

Ionospheric influence on the seismo-telluric current related to electromagnetic signals observed before the Wenchuan MS 8.0 earthquake

Tan

Cao

2016

Solid Earth

View full text Add to dashboard Cite

Abstract. A three-layer (Earth-air-ionosphere) physical model, as well as a two-layer (Earth-air) model, is employed in this paper to investigate the ionospheric effect on the wave fields for a finite length dipole current source co-located at a hypocenter depth and along the main fault of an earthquake when the distance between the epicenter and an observing station is up to 1000 km or even more. The results show that all electrical fields are free of ionospheric effects for different frequencies in a relative short range, e.g., ∼ 300 km for f = 1 Hz, implying the ionospheric influence on electromagnetic fields can be neglected within this range, which becomes smaller as the frequency increases. However, the ionosphere can give a constructive interference to the waves passing through and make them decay slowly when an observation is out of this range; moreover, the ionospheric effect can be up to 1-2 orders of magnitude of the electrical fields. For a ground-based observable 1.3 mV m −1 electric signal at f = 1 Hz 1440 km away from the Wenchuan M S 8.0 earthquake, the expected seismo-telluric current magnitude for the Earth-air-ionosphere model is of 5.0 × 10 7 A, 1 magnitude smaller than the current value of 3.7 × 10 8 A obtained by the Earth-air model free of ionospheric effects. This indicates that the ionosphere facilitates the electromagnetic wave propagation, as if the detectability of the system were improved effectively and it is easier to record a signal even for stations located at distances beyond their detectability thresholds. Furthermore, the radiating patterns of the electrical field components |E x | and |E y | are complementary to each other, although any two-dimensional (2-D) power distribution of these components shows strong power areas as well as weak ones, which is advantageous to register a signal if the observing system is designed to measure both of them instead of only one.

show abstract

Physical interpretation and mathematical simulation of ionospheric precursors of earthquakes at midlatitudes

Cited by 38 publications

References 24 publications

Comment on “An improved coupling model for the lithosphere‐atmosphere‐ionosphere system” by Kuo et al. [2014]

Comment on “An improved coupling model for the lithosphere‐atmosphere‐ionosphere system” by Kuo et al. [2014]

An improved coupling model for the lithosphere‐atmosphere‐ionosphere system

Ionospheric influence on the seismo-telluric current related to electromagnetic signals observed before the Wenchuan <i>M</i><sub><i>S</i></sub> 8.0 earthquake

Contact Info

Product

Resources

About

Physical interpretation and mathematical simulation of ionospheric precursors of earthquakes at midlatitudes

Cited by 38 publications

References 24 publications

Comment on “An improved coupling model for the lithosphere‐atmosphere‐ionosphere system” by Kuo et al. [2014]

Comment on “An improved coupling model for the lithosphere‐atmosphere‐ionosphere system” by Kuo et al. [2014]

An improved coupling model for the lithosphere‐atmosphere‐ionosphere system

Ionospheric influence on the seismo-telluric current related to electromagnetic signals observed before the Wenchuan &lt;i&gt;M&lt;/i&gt;&lt;sub&gt;&lt;i&gt;S&lt;/i&gt;&lt;/sub&gt; 8.0 earthquake

Contact Info

Product

Resources

About

Ionospheric influence on the seismo-telluric current related to electromagnetic signals observed before the Wenchuan <i>M</i><sub><i>S</i></sub> 8.0 earthquake