At mid latitudes, the much larger effect is observed in the component parallel to the magnetic field of the O+ and H+ velocities, see Measurements of the topside ionosphere over Arecibo during the total solar eclipse of February 26, 1998

B. MacPherson, S. A. González, M. P. Sulzer, G. J. Bailey, F. Djuth, P. Rodriguez, Journal of Geophysical Research (Impact Factor: 3.17). 10/2000; 105(A10):23055-23068. DOI:10.1029/2000JA000145

ABSTRACT The Arecibo incoherent scatter radar facility was operated on February 26, 1998, and was used to observe the total solar eclipse that occurred over the Caribbean. A maximum of 87% obscuration was observed over Arecibo at 1430 LT (1830 UT). The radar was operated using an

experimental technique, which uses a 300 μs single/multi-frequency

pulse, to gather data from the altitude range 146-2412 km. The Sheffield

University plasmasphere ionosphere model was used to interpret the

measurements. The electron temperature was found to have decreased by

600 K at 400 km altitude, but the magnitude of the decrease becomes

smaller with increasing altitude. This is shown to be the result of the

lesser degree of obscuration of the solar disk at latitudes north of

Arecibo. Conjugate point photo-electron heating effects are also shown to

play a significant role in the electron energy balance during the

eclipse. The H+ ion temperature exhibited a response to the

eclipse, with temperatures being around 200 K lower than expected at the

time of maximum obscuration. There was relatively little variation

observed in the O+ temperature. The response of the topside

ionosphere is characterized by a downward motion arising from the

contraction of the plasma due to reduced plasma temperatures. This is

most clearly seen in the O+-H+ transition altitude

which falls by 200 km. The transition altitude fully recovers within 2

hours after the eclipse. The location of the transition altitude acts to

mitigate the effects of the eclipse on the topside electron densities.

An edited version of this paper was published by AGU. Copyright 2000 American Geophysical Union. To view the published open abstract, go to http://dx.doi.org and enter the DOI.

Shimazaki formula in anapproimate one and not suitable for the time if solar eclipse.--R>G>Rastogi

Why is Shimazaki fomula is not suitable for the time of eclipse? Have you ever compared a real measurement of peak height with the one inferred from Shimazaki? What are your Justification.