Journal ArticleDOI
On a summer maximum in the occurrence frequency of 150 km (F1) radar echoes over Pohnpei
TLDR
In this article, the occurrence frequency of 150 km (or F1) echoes has a broad but conspicuous maximum during northern summer in this longitude sector with minimal activity in other months.Abstract:
[1] Using three and a half years of 50 MHz radar data collected from Pohnpei, Federated States of Micronesia (6.96°N, 158.19°E geographic, 0.3° magnetic dip latitude), we show for the first time that the occurrence frequency of 150 km (or F1) echoes has a broad but conspicuous maximum during northern summer in this longitude sector with minimal activity in other months. Given a seasonal similarity to sporadic E (Es), we suggest that an Es-layer instability [Cosgrove and Tsunoda, 2002] generates a polarization electric field (), which maps along geomagnetic field lines to the F1 region. There, forms thin plasma sheets that provide gradients to excite 3-m-scale plasma waves via an interchange process.read more
Citations
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Journal ArticleDOI
Equatorial and low latitude ionospheric effects during sudden stratospheric warming events
TL;DR: In this paper, the observed ion-neutral coupling effects at equatorial and low latitudes during large meteorological events called sudden stratospheric warming (SSW) are reviewed.
Journal ArticleDOI
Statistics of 150-km echoes over Jicamarca based on low-power VHF observations
Jorge L. Chau,Erhan Kudeki +1 more
TL;DR: In this article, the authors summarize the statistics of the so-called 150-km echoes obtained with a low-power VHF radar operation at the Jicamarca Radio Observatory (11.97 S, 76.87 W, and 1.3 dip angle at 150km altitude) in Peru.
Proceedings ArticleDOI
Equatorial and low latitude ionospheric effects during sudden stratospheric warming events
Chau,Goncharenko,Fejer,Li +3 more
TL;DR: In this paper, the observed ion-neutral coupling effects at equatorial and low latitudes during large meteorological events called sudden stratospheric warming (SSW) are reviewed.
Journal ArticleDOI
Radar observations of daytime 150‐km echoes from outside the equatorial electrojet belt over Gadanki
A. K. Patra,N. Venkateswara Rao +1 more
TL;DR: In this paper, the authors present the first experimental evidence on the occurrence of daytime 150-km echoes outside the equatorial electrojet belt from Gadanki (13.5° N, 79.2° E, 6.3° dip latitude).
Journal ArticleDOI
Daytime 150‐km echoes observed with the Equatorial Atmosphere Radar in Indonesia: First results
TL;DR: In this paper, the authors used the Equatorial Atmosphere Radar (EAR) from magnetic southern hemisphere (10.36°S magnetic latitude) to detect the 150-km echoing phenomenon.
References
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Journal ArticleDOI
A direction‐dependent instability of sporadic‐E layers in the nighttime midlatitude ionosphere
R. B. Cosgrove,Roland T. Tsunoda +1 more
TL;DR: In this paper, the authors show that the growth rate of the instability depends on the azimuthal alignment of the phase fronts of the plane-wave distortion, a feature that is reminiscient of the Perkins instability.
Journal ArticleDOI
High resolution observations of 150 km echoes at Jicamarca
Erhan Kudeki,Clinton D. Fawcett +1 more
TL;DR: In this article, a gravity wave wind driven interchange instability is suggested as a possible generation mechanism of the field-aligned plasma irregularities responsible for the echoes at Jicamarca, Argentina.
Journal ArticleDOI
Source and identification of heavy ions in the equatorial F layer
TL;DR: In this paper, it was shown that the interpretation of some Ogo 6 retarding potential analyzer (RPA) results in terms of ambient Fe+ ions is correct, but only within dip latitudes of plus or minus 30 degrees.
Journal ArticleDOI
The wind-shear theory of temperate zone sporadic E.
W. I. Axford,D. M. Cunnold +1 more
TL;DR: In this article, the wind-shear theory of sporadic E layer at temperate zone with single ion and many ions, noting electron density, was applied to the problem of electron density.
Journal ArticleDOI
Evidence of a stratified echoing region at 150 kilometers in the vicinity of the magnetic equator during daylight hours
TL;DR: In this article, the authors used the Jicamarca radar observatory near Lima, Peru, to investigate the properties of a region in the vicinity of 150 km in the early part of May 1963, which is well above the 105- to 115-km region attributed to the equatorial electro jet.