THE ELECTRICAL COUPLING MECHANISM IN THE IONOSPHERE.
Abstract
Since the longitudinal conductivity is at least four orders of magnitude higher than the transverse conductivities in the ionosphere, the geomagnetic field lines are ordinarily assumed to be electrical equipotential lines. With this assumption there would be no electric field strength reduction along the geomagnetic field lines. The purpose of this report is to examine the validity of this assumption and to study the significance of the reduction of the electric field strength in the ionosphere along the geomagnetic field lines. An analytic method has been formulated to calculate the reduction in electric field strength. A given source of electric field at a certain layer will be coupled to a higher (or lower) layer along the geomagnetic field lines if the field strength reduction is small. The coupling mechanism is examined for various latitudes and heights, as well as for differences in the scale of the source of the electric field. It has been found that the electrostatic field coupling in the ionosphere is nearly perfect for large scale fields (500 km). For small scale fields (less than 100 km), the coupling depends on the direction along which the static fields are perturbed. Applications have been made to the electric fields of E region irregularities. Their role in producing F region anomalies is discussed. The results suggest that large scale irregularities in the E region are capable of producing F region irregularities in electron density and ionization drifts, the latter being predominantly east-westward. These F region irregularities might result in the observed radio-star scintillations and spread F echoes.
Document Details
- Document Type
- Technical Report
- Publication Date
- May 01, 1967
- Accession Number
- AD0822052
Entities
People
- Dickson Da-jane Fang
Organizations
- Stanford University