The ionic conductivity of electrified clouds

Griffiths, R.F.; Latham, John; Myers, Vernon W.

doi:10.1002/qj.49710042405

Cited by 32 publications

(9 citation statements)

References 11 publications

(5 reference statements)

Supporting

Mentioning

Contrasting

Order By: Relevance

“…This is the same as in the cloud. Phillips (1967) and Griffiths et al (1974) pointed out that the conductivity of the air in the cloud is less than outside a cloud because cloud droplets remove ions. In our model, snowflakes remove ions instead of cloud droplets.…”

Section: Ductivity Of the Air (C)mentioning

confidence: 99%

Numerical Experiments of the Charging Mechanism of Precipitation Particles by the Ion-capture Process below the Cloud Base

Asuma

Kikuchi

1987

Journal of the Meteorological Society of Japan

View full text Add to dashboard Cite

To investigate the mirror image relation (hereinafter, M.I.R.) observed at the ground surface, a new formulation in which snowflakes and snow particles acquire charges by the selective ion capture process is lead forth and one dimensional numerical experiments are carried out in this paper.The M.I.R. is more clear during snowfalls than during rainfalls and charges on these snow particles are also larger than that of raindrops in which the diameter is equivalent to the melted diameter of snow particles. In their experiments, Asuma and Kikuchi (1983), reported that although snowflakes have numerous pores in themselves, the final charges expected from the selective ion capture process are the same as that of a conductive sphere of the same diameter. It is expected therefore that the high porosity of snowflakes leads to the increase of the collection efficiency of ions and it requires a shorter time to attain their final charges. We call this "the penetration effect". The formulation of a charging mechanism for snowflakes including this effect was derived.The modifications of charges on precipitation particles under the cloud base are examined by numerical experiments. Two types of precipitation particles are tested in these experiments, that is, snowflakes and raindrops. In case of snowflakes, the comparison Whipple and Chalmers (1944) formulation with our formulation was discussed. The main results obtained are as follows; (i) There is a tendency that on snowflakes observed on the ground surface hardly keep the electric charges produced in the cloud but raindrops keep the charges produced in the cloud. This tendency would be caused by the differences of their falling speeds.(ii) The penetration effect is more effective near the ground surface where ions are emitted abundantly in the atmosphere by the point discharge.(iii) On the ground surface, the precipitation current and the point discharge current are balanced and this balanced relation brings about the M.I.R.

show abstract

Section: Ductivity Of the Air (C)mentioning

confidence: 99%

Numerical Experiments of the Charging Mechanism of Precipitation Particles by the Ion-capture Process below the Cloud Base

Asuma

Kikuchi

1987

Journal of the Meteorological Society of Japan

View full text Add to dashboard Cite

show abstract

“…In an earlier study, Griffiths et al (1974) have shown that the effect of droplet charge (varied over a wide range) and its distribution over the droplets on normalized conductivity (the ratio of the in-cloud value to the clear-air value at the same altitude) is significantly very small in the weakly-electrified clouds. However, the only significant effect exercised by cloud charge is to introduce an asymmetry into the process of ionic immobilization.…”

Section: Effects Of Single and Multiple Droplet Chargesmentioning

confidence: 99%

“…The above two equations are balanced by the production of ions due to ionization from cosmic rays, i.e., q and loss of ions by various mechanism such as ion-ion recombination, which play a crucial role in ultra-fine particle formation in the lower atmosphere (Mohnen 1977;Yu and Turco 2001), and ion-droplet attachment within the cloud (Griffiths et al 1974). The last term of equations (1) and (2) indicates flux of positive (∇J z1 ) and negative (∇J z2 ) ions, respectively which produces an imbalance between both the ions in a region.…”

Section: Theoretical Formulationmentioning

confidence: 99%

See 1 more Smart Citation

Numerical study for production of space charge within the stratiform cloud

Srivastava

Tripathi

2010

J Earth Syst Sci

View full text Add to dashboard Cite

One dimensional numerical model has been developed to predict the production of space charge and variations in other electrical parameters within the low level stratiform type of cloud having very weak vertical motion. Non-linear coupled differential equations which govern ion concentrations, charged and neutral droplet concentrations and electric field were used. Symmetry has been observed in all the electrical parameters within the cloud. The magnitude of average positive ion concentrations was observed to be high as compared to the negative ion concentrations, which is due to low scavenging rate of positive ions than the negative ions, highly attributed to their mobilities. The rate of scavenging of ions affects the concentration of charged droplets, which eventually influence the electric field and thus the space charge density within the cloud. Maximum electric field (E max ) was observed at middle of the cloud whereas minimum was observed at both the edges of the cloud. Minimum electric field (E min ) was found to be equal and constant (∼ 27 Vm −1 ) for any drop concentration. Net positive and negative space charges were observed at the top and bottom of the cloud, respectively. The simulated results show some discrepancies to the natural condition, which are due to simulations made under some basic assumptions and limitations and that will be incorporated in the future studies for natural cloud condition.

show abstract

“…Under the tropospheric conditions, this coefficient is calculated via the ion diffusion coefficient [50,51]. Under stratospheric conditions, we can estimate the sticking coefficient of the ions to the drops using an approximation of the theory of "collisions" [52]:…”

Section: Dipole Interaction and Chemical Reactions On The Surface Of mentioning

confidence: 99%

The Role of the Dipole Interaction of Molecules with Charged Particles in the Polar Stratosphere

Belikov¹,

Nikolayshvili²

2016

JEASE

View full text Add to dashboard Cite

Our analysis of published results of experiments in the Polar Regions substantiates and further develops our new approach to the photochemical processes in the polar stratosphere involving the charged particles. The dipole interaction of molecules with charged particles, primarily with ions, leads to the adhesion and disintegration of a number of molecules including ozone. Molecules acquire additional energy on the surface of the charged particles, enabling reactions that are not possible in space. Galactic cosmic rays are the main source of ions in the polar stratosphere, their equilibrium concentration at altitudes of 15 to 25 km can reach up ~ (1-5) × 10 3 ions/cm 3 . Estimations show that if the ozone destruction in the regime of "collision" with ions then the lifetime of ozone will vary from 10 days to 2 months. We suppose that alongside with the chlorine mechanism of ozone destruction there is a mechanism of ozone decay on a charged particle which can act also at those latitudes and altitudes where chlorine oxide ClO is absent, as well as in the night conditions. Here, we demonstrated the close connection of photochemical processes with the dynamic, electrical and condensational phenomena in the stratosphere, in particular, with the accumulation of unipolar charged particles on the upper and lower boundaries of the polar stratospheric clouds and aerosol layers as a result of the activity of the global electric circuit.

show abstract

The ionic conductivity of electrified clouds

Cited by 32 publications

References 11 publications

Numerical Experiments of the Charging Mechanism of Precipitation Particles by the Ion-capture Process below the Cloud Base

Numerical Experiments of the Charging Mechanism of Precipitation Particles by the Ion-capture Process below the Cloud Base

Numerical study for production of space charge within the stratiform cloud

The Role of the Dipole Interaction of Molecules with Charged Particles in the Polar Stratosphere

Contact Info

Product

Resources

About