Fabry-Perot interferometer measurements of neutral winds and F2 layer variations at the magnetic equator

Abstract

Abstract. This letter presents some night-time observations of neutral wind variations at F2 layer levels near the dip equator, measured by the Fabry-Perot interferometer set up in 1994 at Korhogo (Ivory Coast, geographic latitude 9.25°N, longitude 355°E, dip latitude A2.5°). Our instrument uses the 630 nm (O 1

An investigation of the ionospheric F region near the EIA crest in India using OI 777.4 and 630.0 nm nightglow observations

“…Unfortunately, the observational period of these reports was different from that of our measurements. Sethi et al (2004) Yadav et al (2010) found the median values of foF2 to vary between ∼ 2.9 and 5.4 MHz during the September-October equinox, while we observed foF2 CP1 and foF2 CP2 in the range of 3.0-4.4 and 2.1-3.5 MHz, respectively. During the post-midnight hours, these authors observed foF2 in the 2.2-3.0 MHz range, whereas airglowderived foF2 CP1 and foF2 CP2 were in the range of 3.3-4.0 and 2.4-3.1 MHz, respectively.…”

“…Ideally a comparison with co-located ionospheric measurements under similar geophysical conditions is a must to assess our measurements. However, due to the lack of such supporting data during our observational period, we looked at NmF2 and hmF2 measurements previously reported by Sethi et al (2004), Yadav et al (2010) and Luan et al (2015) over latitudes relatively close to that of Allahabad. Reports of Sethi et al (2004) and Yadav et al (2010) utilized digital ionosonde measurements over India, while that of Luan et al (2015) was based on COSMIC measurements.…”

Equatorial vertical plasma drifts and the measured and IRI model-predicted F 2-layer parameters above Ouagadougou during solar minimum

“…A regular feature in the equatorial ionosphere, morning enhancements observed virtually in all F 2 -layer parameters is probably due to persistent photoelectron heating (e.g., Zhang et al, 1999). Thermospheric neutral winds have also been recognized to be an important candidate responsible in part to the nighttime behavior of equatorial ionosphere (e.g., Villa et al, 1998).…”

Calculation of meridional neutral winds in the middle latitudes from the Irkutsk incoherent scatter radar

“…A very important and fine‐scale probe of ionospheric plasma dynamics is provided by a global network of incoherent scatter radars, especially when these radars are combined with other remote sensing instruments [ Griffin et al , , ] ranging from optical Fabry‐Pérot interferometers [ Vila et al , ], ionosondes [ Lei et al , ; Shchepkin et al , ], to GPS satellites and instruments mounted on artificial satellites orbiting the Earth [ Yizengaw , ]. In practice, a power spectrum or its Fourier transform equivalent autocorrelation function (ACF) is usually used in the incoherent scatter radar technique to determine radial plasma velocity.…”