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The Electric Conductivity in the Ionosphere Essay examples

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The electric conductivity in the ionosphere associates the electric current and the electric field by Ohm's law.
The conductivity includes the Pedersen component ("Expression 1") parallel to the electric field and the Hall component ("Expression 2") perpendicular to the electric and the magnetic field.
The conductivities usually concentrate between 100 and 130 km altitudes in the central E region where ions and electrons can move separately.
Conductivities are proportional to plasma densities.
Daytime plasmas are mainly created by the solar extreme ultraviolet (EUV) radiation into the neutral atmosphere.
Thus daytime plasma densities depend on the solar zenith angle (SZA, "Expression 3").
Height profiles of such plasma densities are…show more content…
In contrast, other studies assumed that conductances behave as Chapman layers and reported significant possible contribution from the attachment loss process, which is dominant in the ionospheric F region {Brekke_A_1988_AG_AURORAL_CONDUCTANCES, Moen_J_1993_GRL_THE_CONDUCTANCES, Brekke_A_2013_BOOK_PHYSICS_ATMOSPHERE.
In summary, SZA dependences are qualitatively different among previous studies.
The purpose of this study is to find simple and essential approximations of conductances against SZA.
In particular, we will express the Hall to Pedersen conductance ratio as a function of SZA.
We will conclude that the daytime conductance can be understood by the Chapman theory after additional considerations including (1) upward gradient of the atmospheric temperature, (2) vertically-flat plasma density profile in the topside E region, and (3) variations of conductance layer thickness.
Conductances are also dependent of the incident solar flux and the local magnetic strength.
Such additional dependences will be studied in the future after the SZA dependences are established.
Both Solar X-ray and EUV product ionospheric plasmas e.g., {Solomon_Qian_2005JGR_SOLAR_IRRADIANCE but we simply call them as EUV in this study.
We excluded plasma productions caused by precipitating electrons, which is supposed to be
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