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E. A. Mareev, V. N. Stasenko, A. A. Bulatov, S. O. Dementyeva, A. A. Evtushenko, N. V. Ilin, ...
In the fair weather electricity research great attention is given to the electrode
effect. In [13] the variability of the electrical parameters under the influence of
the electrode effect is investigated, and two extreme cases of the electrode effect,
classical and turbulent, are considered. It was found that under the ‘fair weather’
conditions the space electric charge is positive near the ground, and the scale of
its distribution is determined by the electrode layer thickness and is equal to
several metres. The values of the electric charge density are defined by both the
power of the ion formation source and the magnitude of the electric field. On the
basis of the research results recommendations for monitoring atmospheric elec‑
trical parameters were provided [14].
In [15] a non-stationary electrodynamic model was developed of atmospher‑
ic turbulence in the surface layer allowing for multiple-charged aerosol particles.
The stability, convergence and conservativeness of the schemes employed were
proved. On the basis of experimental observations the conditions for the classical
and turbulent electrode effect were established, and the agreement of the ob‑
tained model calculations with the experimental data was estimated. The approx‑
imate analytical solution was obtained of the boundary value problem for the
classical electrode effect in the surface atmosphere. It was shown that the ob‑
tained solution is an exact analytical solution for a special case of the problem,
which takes place in the real atmosphere. Approximate asymptotic solutions
corresponding to low turbulent mixing were found for the cases of stable and
neutral atmospheric stratification [16]. In [17] the well-posed problems were
analysed for the one‑dimensional steady‑state system
of equations describing the
classical electrode effect in the atmospheric surface layer; a complete classifica‑
tion of the solution types was obtained, their properties were investigated, and
analytical expressions were derived for the dependence of the ion concentration
on the electric field intensity. New classes of solutions to the system were found,
characterized by the presence of layers with infinitely increasing conductivity
and charge density.
2. The global electric circuit
The concept of the global electric circuit (GEC)
is fundamentally important
for the studies of atmospheric electricity, since it combines all electrical process‑
es in the atmosphere into a single electric network. Over the last few years the
interest in GEC has increased owing to the fact that its parameters can serve as
indicators of the state of Earth’s climate system and Earth’s space environment.
Much attention has been given recently to modelling the GEC and its particu‑
lar components, especially the most important part of the GEC composed of
quasi‑stationary distribution of
the electric current, maintained by thunderstorm
generators. In [18] steady-state and non-stationary GEC models were
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Atmospheric
Electricity
constructed; in these models it is possible to uniquely determine the spatial dis‑
tribution of the electric potential for arbitrary (known) distribution of conductiv‑
ity in the atmosphere, once GEC generators are described
in the form of a source
current density distribution. An important distinctive feature of these models is
the boundary value problem in which the ionospheric potential — one of the
most important GEC parameters, defined as the potential difference between the
Earth’s surface and the ionosphere — is uniquely determined (as a constant or
as a function of time) from the solution of equations for the potential and is not
specified explicitly; furthermore, it was demonstrated that this boundary value
problem is the only possible one, if the atmosphere has the geometry of a spher‑
ical layer. Besides the implementation of corresponding numerical models on the
basis of the finite element method, it was shown that the ionospheric potential in
many simple problems can be expressed analytically as a function of the problem
parameters [18, 19]. A number of general questions concerning GEC modelling
in both plane-parallel and spherical geometry were discussed in [20].
In [21] the impact of lightning discharges on the GEC was analysed and
discussed. On the basis of a quasi-stationary GEC model it was shown that intr‑
acloud discharges and positive cloud-to-ground discharges result in a decrease
in the ionospheric potential, whereas negative cloud-to-ground discharges result
in its increase. Quantitative estimates demonstrated that the ionospheric potential
variation due to negative cloud-to-ground discharges do not exceed 10% of its
quasi-stationary value.
The interaction of the GEC with ionospheric and lithospheric processes is
another important direction of research. In [22] an attempt was made to consider
the influence of the ionospheric generator on the atmospheric electric field. The
vertical profile of atmospheric conductivity was assumed to be piecewise-expo‑
nential, and at the upper boundary of the atmosphere a certain distribution of the
potential was specified. Within the framework of the non-stationary problem the
estimates were obtained for the stabilization time of the stationary electric field
in the lower atmosphere when the ionospheric generator is turned on and for the
dissipation time of the electric field in the absence of generators. In [23, 24]
penetration of the electric field from the atmosphere near the Earth’s surface to
the ionosphere was modelled, which is important for the problem of iono‑
sphere-lithosphere coupling. In such models the vertical component of the elec‑
tric field at the Earth’s surface is specified, and the equation for the potential,
allowing for conductivity anisotropy, is solved. The authors calculated that the
absolute value of the resulting electric field generated in the ionosphere by means
of such mechanism is much less than it is usually supposed in connection with
observations of the ionospheric precursors of earthquakes [24]. The coupling of
lithospheric and ionospheric processes through the GEC was also discussed in
[25]. In [26] hypothetical ‘seismogenic currents’ flowing between the tectonic