Transcript ФОРБУШ ПОНИЖЕНИЯ И ЭФФЕКТЫ ТЕРМИНАТОРА

NOVEL MODEL OF ATMOSPHERIC
ELECTRIC FIELD
V. Kuznetsov
Institute of Space Physical Researches,
KAMCHATKA, RUSSIA
[email protected] [email protected]
http://www.ikir.kamchatka.ru/vvk/
- Novel model of atmospheric electric field (AEF) based on
the idea of AEF generation due to electric charges
separation in “fair weather” atmosphere is proposed.
- If thunderstorms are absent then the electric charges in
the atmosphere are formed through its ionization by
galactic cosmic rays (GCR).
- Light positive ions are lifted by upward currents to the
upper layers of atmosphere and heavy negative aerosols
fall to the Earth.
- The model provides the explanation for Carnegie curve
of AEF and for some other features of atmospheric
electricity; in particular, AEF behavior and Forbush
decreases of GCR during geomagnetic disturbances.
- The problem of AEF secular decrease against the Earth
surface temperature, the results of experiments on AEF
excitation, AEF behavior during earthquakes and
seismovibrators run are discussed.
• Motivation:
• ЕZ value which is almost constant for different Earth’s regions
and in different seasons ЕZ = 130 V/m.
• Fine day electricity is associated with thunderstorm cloud
activity, i.e. with the factor, which is excluded as an anomalous
one in the investigations of “fair weather” field.
Atmospheric electric field model.
Electric charges in the atmosphere..
The essence of our idea is that thunderstorms and strikes have
impact on AEF, but they are not its main source.
According to the model charge formation (due to atmosphere
ionization by GCR) and separation (due to the difference in
charged aerosol falling rates) occur in “fair weather”
atmosphere. In order to prove the case it is necessary, at first,
to find convincing arguments that GCR can bring electric
charge to the Earth, which is not less in value than the Earth
looses per unit time I = dQ/dt = 103 coulomb/s.
Ion formation rate q is associated with cosmic ray flux density Р
by the ratio: q = Р σ No, σ –effective cross-section of air
ionization by cosmic rays, No – air molecule concentration.
Altitude distribution of electric
charge density in the atmosphere
(Marsh, Svensmark, 2000).
As it is follows from the picture
the air ionization in the part of the
atmosphere, which is involved in
AEF generation is due to GCR.
In the works (Ermakov et al., 1997;
Ermakov, Stozhkov, 2004) it was
experimentally ascertained that
atmospheric air ionization by cosmic
rays q occurs according
to the ion balance linear equation:
q=βN
but not to the usually applied
quadratic equation q = αN2. Here α –
volume recombination coefficient, β –
linear recombination coefficient, these coefficients are different in value
and dimension.
The discovered dependence points that the relation between ion
concentration in the atmosphere and cosmic ray flux is stronger (N ~ Р),
than it was earlier supposed (N ~ Р 1/2). This approach gives more
confidence that GCR have significant impact on AEF and atmosphere
conductivity current j. It is illustrated pictorially in Fig. where stable
correlation between GCR flux N and j current (dQ/dt) is shown.
In the global scale there are three types of
particles size distribution in the troposphere:
“background”, “oceanic” and “continental”.
Idealized curves, exhibiting the features of these
distributions are shown in Fig. (Ivlev, 1999).
- The maximum aerosol concentration
corresponds to the size r ≥ 0.1 mkm (from this
point on we shall be interested in the particles
particularly of this size).
- Charged particles separation occurs on water
droplets and heavy ions, that is why it is
necessary to
find out if there are appropriate conditions in the
atmosphere for condensation and coagulation of
the droplets with the radius r ≥ 0.1 mkm.
• Charged water aerosols and heavy ions fall to the Earth’s
surface and transfer their charge to it. Aerosols evaporate when
falling to the Earth. The critical size of particles for starting to
evaporate was estimated in (Harrison, 2001).
• It was shown that the most optimal size of water aerosol is 0.13
mkm.
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As it is shown in Fig.,
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oversaturation value in
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the optimal case
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is Sc ≈ 1.006 (0.6%).
• Critical water vapor oversaturation dependence on temperature
Sc(T) is illustrated in Fig., it was done by Artukhin A.S.
• The calculations were carried out according both to the
classical theory (1) and to the quantum-statistical one (2).
• In the latter case the results of the calculations were almost
similar to the experimental points, defined in the presence of
supersonic air flow in cloud and diffusive chambers.
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Water aerosol formation region
with the typical size
r ≥ 0.1 mkm
coincides with the region of
maximum ion concentration
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generated by GCR stagnation.
Charge separation in gravitational field.
• Frenkel evaluates ЕZ value inside a cloud using its water
content М:
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ЕZ = εо Mgζ/6πησe.
• where: M – cloud water content (М ≈ 1 g/m3 in a thunderstorm
cloud), g – acceleration of gravity, ζ – water electric potential
(ζ ≈ 0.25 V), η – air viscosity (η ≈ 10-5 Pа s),
σe- electroconductivity (σ ≈ 10-14 Ω-1 m-1); ЕZ ≈ 104 V/m.
• Following Frenkel’s formula we estimate Е value appearing if
charge separation takes place in “fair weather” water saturated
atmosphere. Atmosphere water content (in the form of water
aerosols) M for ЕZ = 100 V/m should be a 100 times as little as
in a cloud, i.e. М = 0.01 g/m3.. Realization of certain pT
conditions is necessary for small aerosos to be generated in the
atmosphere.
E polarity. Condensation and evaporation processes
effects.
• AEF model we consider, as well as Frenkel model, determines
the Earth charge polarity by the fact that the droplets carrying a
negative charge are heavier than the droplets carrying a
positive charge.
• The physics of competition between condensation and
evaporation processes in the atmosphere.
• Condensation rate К (s-1 cm-3) can be evaluated via vapor
temperature:
•
К  exp (-2 + 1/T) .
• In evaporation conditions (boiling) droplets collapse and vapor
“bubbles” generate with the rate J (s-1 cm-3):
•
J  exp(-W/kT),
here W – energy necessary for the generation of a bubble with
a critical size. Temperature dependence of К and J is shown in
the next Fig.
E polarity. Condensation and evaporation processes
effects.
• Temperature dependence (lg)
of condensation (К) and
evaporation (J) rates - the
upper part.
• At the bottom is the polarity of
electric field Е(z) as a function
of the ratio J and К: Е + when
J > К and Е -, when J < К.
• E = 0, when T” ≈ 24 ˚ C
Global distribution of atmospheric electric fields: electric
field Е(z) & Earth temperature T.
Global distribution of atmospheric electric fields: electric
field Еz & Earth temperature T.
• In the last 80 years Еz-value has decreased by half: Еz’ ≈ 2.
• The Earth surface temperature has increased by 0.7 – 0.8 ˚:T’ =
0.06, namely: T’/E’ = 0.03.
• Water concentration of the Earth atmosphere depends on the
nucleation rate:
• M ~ nZ (4πrPK)/(2π m kT)1/2, here n - water concentration, r –
radius, m - mass, Z – Zeldovitch factor, Р – pressure,
• К  exp (-T), k – Boltzmann constant. Since ЕZ depends solely
upon temperature, we obtain:
ЕZ  M  T-1/2 exp (-T).
• If Т = аt, then Т’ = dT/dt = а. Substituting Т = аt into the
formula for Еz’ we have
Еz’ ≈ [exp(-at)(1 + 2at)/а] ×(at)3/2
and assuming t =1 we obtain the relation T’/E’ ≈ 2а3/2.
Revealed in measurements a equal to а = 0.06 ensures
T’/E’ = 0.03.
AEF Universal diurnal variation. Carnegie curve.
• a – Cosmic ray intensity
distribution, obtained by UoSAT
spacecraft from 09.1988 to
05.1992 (Glassmeier et al.,
2002) in the northern
hemisphere (the North is in the
bottom);
• b –isoline of geomagnetic field
H-component value 10 μT
(marked by black area, the
North is in the bottom);
• c –Atmospheric electric field ЕZ
UT-variation.
• Carnegie curve AEF is
accounted for assymmetry of
the geomagnetic field structure.
AEF Universal diurnal variation. Model.
• Averaged atmospheric electric field value (relative units) at
Vostok, Antarctica, measured during 1998 (Corney, et al.,
2003).
• Earth’s orientation is as regards to GCR flux direction (arrows)
at equinox, in winter and in summer.
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Angles and “funnels”
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correspond to GMA [2]:
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the Canadian GMA is
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located
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at the latitude
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φ1 ≈ 55° N,
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the Siberian GMA is at
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φ2 ≈ 63° N.
Universal variation in the ionosphere.
foF2 universal variation averaged for the years of minima
(а), maxima (b) for three cycles of solar activity
depending on season (c) (Kuznetsov et al., 1998).
Universal variation in the ionosphere.
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Magnetic field line structure in the
region of Northern Magnetic Pole
(NMP) and Global Magnetic
Anomalies: the Canadian Anomaly
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(CA) and the Siberian Anomaly (SA).
• Correlation of Forbush decreases in GCR with EZ ones
observed – a;
• b – GCR spectrum pointing at the number N of particles with
energy E: 1 – region of low energy GCR, 2 – that of middle
energy GCR, 3 - that of higher energy GCR.
• Altitude distribution of GCR density n (r.u.) of GCR providing
the EZ generation distributed along the altitude h (km).
NOVEL MODEL OF ATMOSPHERIC
ELECTRIC FIELG
MAIN PRINCIPLES OF AEF MODEL:
1. ATMOSPHERE IONIZATION BY GCR.
2. CHARGES SEPARATION BY THE FINE AEROSOLS OF
ATMOSPHERE IN FAIR- WEATHER CONDITIONS.
3. TIME STABILITY OF ATMOSPHERIC ELECTRIC FIELD
PROVIDED BY CONSTANCY OF THE EARTH TEMPERATURE
AND OF THE RATES OF PHASE CHANGES IN WATER.
4. MODEL OF THE UNITARY VARIATION (Carnegie curve )
FOLLOWING FROM ASSYMETRY OF THE GEOMAGNETIC
FIELD.