Validation of Charge Distribution Models of Lightning Stepped Leaders from Electric Field Data

Abstract. The electron temperature (Te), electron density (Ne), and two components of the electric field were measured from the height of 90 km to 150 km by one of the sounding rockets launched during the SEEK-2 campaign. The rocket went through sporadic E layer (Es) at the height of 102 km–109 km during ascent and 99 km–108 km during decent, respectively. The energy density of thermal electrons calculated from Ne and Te shows the broad maximum in the height range of 100–110 km, and it decreases towards the lower and higher altitudes, which implies that a heat source exists in the height region of 100 km–110 km. A 3-D picture of Es, that was drawn by using Te, Ne, and the electric field data, corresponded to the computer simulation; the main structure of Es is projected to a higher altitude along the magnetic line of force, thus producing irregular structures of Te, Ne and electric field in higher altitude.

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Water in an External Electric Field: Comparing Charge Distribution Methods Using ReaxFF Simulations

Journal of Chemical Theory and Computation ◽

10.1021/acs.jctc.1c00975 ◽

2021 ◽

Author(s):

Jason P. Koski ◽

Stan G. Moore ◽

Raymond C. Clay ◽

Kurt A. O’Hearn ◽

H. Metin Aktulga ◽

...

Keyword(s):

Electric Field ◽

External Electric Field ◽

Charge Distribution

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Effects of three-dimensional electric field on saltation during dust storms: An observational and numerical study

10.5194/acp-2019-439 ◽

2019 ◽

Author(s):

Huan Zhang ◽

You-He Zhou

Keyword(s):

Electric Field ◽

Field Data ◽

Numerical Study ◽

Three Dimensional ◽

Vertical Component ◽

Dust Storms ◽

Dust Particles ◽

Sand Transport ◽

Dust Transport ◽

Dust Events

Abstract. Particle tribo-electrification being ubiquitous in nature and industry, potentially plays a key role in dust events, including the lifting and transport of sand and dust particles. However, the properties of electric field (E-field) and its influences on saltation during dust storms remain obscure as the high complexity of dust storms and the existing numerical studies mainly limited to one-dimensional (1-D) E-field. Here, we quantify the effects of real three-dimensional (3-D) E-field on saltation, through a combination of field observations and numerical modelling. The 3-D E-fields in the sub-meter layer from 0.05 to 0.7 m above the ground during a dust storm are measured at Qingtu Lake Observation Array site. The measured results show that each component of the 3-D E-field data nearly collapses on a single 3-order polynomial curve when normalized. Interestingly, the vertical component of the 3-D E-field increases with increasing height in the saltation layer during dust storms. Such 3-D E-field data close to the ground within a few centimeters has never been reported and formulated before. Using the discrete element method, we then develop a comprehensive saltation model, in which the tribo-electrification between particle-particle midair collisions is explicitly accounted for, allowing us to evaluate the tribo-electrification in saltation properly. By combining the results of measurements and modelling, we find that although the vertical component of the E-field (i.e. 1-D E-field) inhibits sand transport, 3-D E-field enhances sand transport substantially. Furthermore, the model predicts that 3-D E-field enhances the total mass flux by up to 63 %. This suggests that a truly 3-D E-field consideration is necessary if one is to explain precisely how the E-field affects saltation during dust storms. These results will further improve our understanding of particle tribo-electrification in saltation and help to provide more accurate characterizations of sand and dust transport during dust storms.

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A method to estimate whistler wave vector from polarization using three-component electric field data

Radio Science ◽

10.1002/2013rs005335 ◽

2014 ◽

Vol 49 (3) ◽

pp. 131-145 ◽

Cited By ~ 5

Author(s):

Abram R. Jacobson ◽

Robert H. Holzworth ◽

Robert Pfaff ◽

Roderick Heelis ◽

Patrick Colestock

Keyword(s):

Electric Field ◽

Wave Vector ◽

Field Data ◽

Whistler Wave

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Effects of electrical anisotropy on long-offset transient electromagnetic data

Geophysical Journal International ◽

10.1093/gji/ggaa213 ◽

2020 ◽

Vol 222 (2) ◽

pp. 1074-1089 ◽

Cited By ~ 1

Author(s):

Yajun Liu ◽

Pritam Yogeshwar ◽

Xiangyun Hu ◽

Ronghua Peng ◽

Bülent Tezkan ◽

...

Keyword(s):

Electric Field ◽

Field Data ◽

Large Scale ◽

Mining Area ◽

Black Shales ◽

Electrical Anisotropy ◽

Anisotropic Models ◽

Data Inversion ◽

Transient Electromagnetic ◽

Long Offset

SUMMARY Electrical anisotropy of formations has been long recognized by field and laboratory evidence. However, most interpretations of long-offset transient electromagnetic (LOTEM) data are based on the assumption of an electrical isotropic earth. Neglecting electrical anisotropy of formations may cause severe misleading interpretations in regions with strong electrical anisotropy. During a large scale LOTEM survey in a former mining area in Eastern Germany, data was acquired over black shale formations. These black shales are expected to produce a pronounced bulk anisotropy. Here, we investigate the effects of electrical anisotropy on LOTEM responses through numerical simulation using a finite-volume time-domain (FVTD) algorithm. On the basis of isotropic models obtained from LOTEM field data, various anisotropic models are developed and analysed. Numerical results demonstrate that the presence of electrical anisotropy has a significant influence on LOTEM responses. Based on the numerical modelling results, an isolated deep conductive anomaly presented in the 2-D isotropic LOTEM electric field data inversion result is identified as a possible artifact introduced by using an isotropic inversion scheme. Trial-and-error forward modelling of the LOTEM electric field data using an anisotropic conductivity model can explain the data and results in a reasonable quantitative data fit. The derived anisotropic 2-D model is consistent with the prior geological information.

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Reconstructing the electrical structure of dust storms from locally observed electric field data

Nature Communications ◽

10.1038/s41467-020-18759-0 ◽

2020 ◽

Vol 11 (1) ◽

Author(s):

Huan Zhang ◽

You-He Zhou

Keyword(s):

Electric Field ◽

Charge Density ◽

Space Charge ◽

Charge Separation ◽

Field Data ◽

Space Charge Density ◽

Dust Storms ◽

Dust Particles ◽

Electrical Structure ◽

Separation Mechanisms

Abstract While the electrification of dust storms is known to substantially affect the lifting and transport of dust particles, the electrical structure of dust storms and its underlying charge separation mechanisms are largely unclear. Here we present an inversion method, which is based on the Tikhonov regularization for inverting the electric field data collected in a near-ground observation array, to reconstruct the space-charge density and electric field in dust storms. After verifying the stability, robustness, and accuracy of the inversion procedure, we find that the reconstructed space-charge density exhibits a universal three-dimensional mosaic pattern of oppositely charged regions, probably due to the charge separation by turbulence. Furthermore, there are significant linear relationships between the reconstructed space-charge densities and measured PM10 dust concentrations at each measurement point, suggesting a multi-point large-scale charge equilibrium phenomenon in dust storms. These findings refine our understanding of charge separation mechanisms and particle transport in dust storms.

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