Atmospheric Electric Field Ez Research Articles

Study of the electric field variation based on preliminary observations at the ENU cosmophysical complex in 2020

The atmospheric electric field Ez is the most urgent problem of study of the physics of the atmosphere and the processes occurring in it. The conducted studies show the relationship of the electric field with atmospheric processes. Monitoring its changes is necessary to solve practical problems. This article presents brief characteristics of the installation of the EFM-100 electrostatic fluxmeter of the scientific cosmophysical experimental complex at the L.N. Gumilyov Eurasian National University (ENU) and its experimental data obtained in 2020. The article presents the results of observation of atmospheric-electrical characteristics nearthe Earth's surface and monitoring of the electric field of the atmosphere of the city of Nur-Sultan, in particular, estimates of the variation of the electric field of the surface layer of the atmosphere during sunrise and sunset based on data obtained by the EFM-100 fluxmeter. The comparison of meteorological data with the data of the electric field strength of the atmosphere is given. The analysis of the days and months in September and October 2020, when the conditions of “good weather” were manifested, was carried out. The series of electric field data obtained at other measuring stations show the characteristic periodicity of the electric field behavior. It is established that the value of the atmospheric electric field increases during sunrise with the manifestation of the solar terminator effect. It is interesting to study the relationship between the magnitude of the electric field of the atmosphere and the intensity of the cosmic ray flux, especially in the case of Forbush effects. The data of the ENU ground-based experimental complex allows us to conduct research on the study of atmospheric physics, including atomic electricity, as well as their interaction with cosmic rays and meto-conditions.

Electric Mode Excitation in the Atmosphere by Magnetospheric Impulses and ULF Waves

Variations of vertical atmospheric electric field Ez have been attributed mainly to meteorological processes. On the other hand, the theory of electromagnetic waves in the atmosphere, between the bottom ionosphere and earth’s surface, predicts two modes, magnetic H (TE) and electric E (TH) modes, where the E-mode has a vertical electric field component, Ez. Past attempts to find signatures of ULF (periods from fractions to tens of minutes) disturbances in Ez gave contradictory results. Recently, study of ULF disturbances of atmospheric electric field became feasible thanks to project GLOCAEM, which united stations with 1 sec measurements of potential gradient. These data enable us to address the long-standing problem of the coupling between atmospheric electricity and space weather disturbances at ULF time scales. Also, we have reexamined results of earlier balloon-born electric field and ground magnetic field measurements in Antarctica. Transmission of storm sudden commencement (SSC) impulses to lower latitudes was often interpreted as excitation of the electric TH0 mode, instantly propagating along the ionosphere–ground waveguide. According to this theoretical estimate, even a weak magnetic signature of the E-mode ∼1 nT must be accompanied by a burst of Ez well exceeding the atmospheric potential gradient. We have examined simultaneous records of magnetometers and electric field-mills during >50 SSC events in 2007–2019 in search for signatures of E-mode. However, the observed Ez disturbance never exceeded background fluctuations ∼10 V/m, much less than expected for the TH0 mode. We constructed a model of the electromagnetic ULF response to an oscillating magnetospheric field-aligned current incident onto the realistic ionosphere and atmosphere. The model is based on numerical solution of the full-wave equations in the atmospheric-ionospheric collisional plasma, using parameters that were reconstructed using the IRI model. We have calculated the vertical and horizontal distributions of magnetic and electric fields of both H- and E-modes excited by magnetospheric field-aligned currents. The model predicts that the excitation rate of the E-mode by magnetospheric disturbances is low, so only a weak Ez response with a magnitude of ∼several V/m will be produced by ∼100 nT geomagnetic disturbance. However, at balloon heights (∼30 km), electric field of the E-mode becomes dominating. Predicted amplitudes of horizontal electric field in the atmosphere induced by Pc5 pulsations and travelling convection vortices, about tens of mV/m, are in good agreement with balloon electric field and ground magnetometer observations.

Weather factor effects on electric parameters in the lower atmosphere

In order to study the factors influencing the formation of the vertical component of atmospheric electric field (AEF) strength Ez, the data on meteorological parameters (atmospheric pressure, air temperature, and snow depth) are applied, as well as the data of radon Rn emanation into the atmosphere. Determined is the seasonal dependence on the radon emanation to the atmospheric surface layer due to the decrease in the upper soil layer permeability in wintertime that results in the decrease in the surface layer ionization which explains the difference between the maximum and minimum values of electric field strength within the annual variations amounting to ∼100 V/m for the observational period. It is demonstrated that during the negative mean diurnal temperatures (November-April), the cyclone arrival from southern directions is accompanied by significant decrease in AEF Ez due to the increase in the radon flow under the influence of considerable fall of atmospheric pressure and dramatic warming by 10–15°C resulting in the increase in upper soil layer permeability.

The atmospheric electric field during the total solar eclipse of 2008

The results of the atmospheric electric field (AEF) measurements using two Gradient electric meters dur� ing the total solar eclipse in Novosibirsk on August 1, 2008, are presented in the paper. The results are simi� lar to the results obtained earlier; however, their inter� pretation is significantly different. The model of this phenomenon is discussed, according to which the main influence factor at the moment of the eclipse is cooling of the surface and lower atmospheric layer. It is known that a temperature decrease leads to an increase in the AEF. The solar eclipse is quite a fast process; its duration is comparable with the character� istic time of conductivity in the atmosphere. In such a situation, during the discharge of condenser Earth– ionosphere, a displacement current (convective cur� rent) can appear. In this case, at the moment of the maximum AEF, the derivative should also be maximal, which was recorded in our case and in the majority of the previous observations on the behavior of the atmo� spheric electric field at the moment of a solar eclipse. Investigation of the effects in atmospheric electric� ity during solar eclipses has a long history; however, the majority of papers were published in the 1970s and 1980s. The results are very contradictory both in the recorded anomalies and in the interpretation, which is explained by the difference in the applied instruments and in the conditions of observations, first of all, mete� orological [1–7]. Figure 1 shows variations in the vertical component Ez of the atmospheric electric field (AEF) strength on August 1, 2008, at two points on the territory of the Novosibirsk Geophysical Observatory located at a dis� tance of approximately 1 km from each other. The eclipse effect is clearly manifested in the records of two parameters, first of all, as a sharp increase in the AEF stress during the phase of the total coverage. At both points, Ez decreases before the beginning of the eclipse; however, the character of the variation is dif� ferent. The anomaly during the eclipse is quite strong over the background of the mean level of E z in nonper� turbed days (approximately 500 V/m). We interpret this result within a principally new model of the AEF [8], which is based on the idea of separation of charges in the atmosphere due to the gravity field. Our model of the AEF is a development of Frenkel’s idea about the separation of the electric charges in a thunderstorm cloud applied to the atmo� sphere of “good weather.” According to the model, electric charges in the atmosphere are formed due to its ionization by galactic cosmic rays (GCRs). Separa� tion of the charges occurs in the gravity field of the Earth due to the fact that negative charges condense water vapor more intensely than positive ones and appear heavier than positive charges. The value of the atmospheric electric field Ez can be estimated using the relation obtained by Frenkel taking into account the separation of the charges on water drops with radius r [9]: Ez = , where M is the amount of water in the atmosphere M = 10 –2 g/m 3 (in a thunderstorm cloud M ≈ 1 1 g/m 3 ), g is accelera� tion due to gravity, ζ is the electric kinetic potential of water (ζ ≈ 0.25 v), η is viscosity of the air (η ≈10 –5 Pa s), σ e is electric conductivity (σ e ≈ 10 –14 Ohm –1 m –1 ); and Ez ≈ 100 v/m (in a thunderstorm cloud Ez ≈ 10 4 v/m). According to a simplified and modified version of Frenkel’s relation [10], the condensation rate (s –1 /cm –3 )

Morning polar substorms and variations in the atmospheric electric field

The effects of morning magnetospheric substorms in the variations in near-Earth atmospheric electricity according to the observations of the electric field vertical component (Ez), at Hornsund polar observatory (Spitsbergen). The Ez, data, obtained under the conditions of fair weather (i.e., in the absence of a strong wind, precipitation, and fog), are analyzed. An analysis of the observations indicated that the development of a magnetospheric substorm in the Earth’s morning sector is as a rule accompanied by positive deviations in Ez, independently of the Hornsund location: in the polar cap or at its boundary. In all considered events, Hornsund was located near the center of the morning convection vortex. In the evening sector, when Hornsund fell in the region of evening convection vortex, the development of a geomagnetic substorm was accompanied by negative deviations in Ez., It has been concluded that the variations in the atmospheric electric field Ez), at polar latitudes, observed during the development of magnetospheric substorms, result from the penetration of electric fields of polar ionospheric convection (which are intensified during a substorm) to the Earth’s surface.