on the occurrence and motion of decametre-scale irregularities in the sub-auroral, auroral, and polar cap ionosphere

Clicks: 119
ID: 208081
2003
Free PDF
Article Quality & Performance Metrics
Overall Quality
Not rated
Combines reader engagement with the AI quality analysis. This article has not been analysed, so there is no overall score — reader engagement is measured and shown alongside.
AI Quality Assessment
Not analyzed
Readership in this journal
Steady

Ranked #252 of 484 articles by views in journal of food measurement and characterization

Most read Least read

Bar heights use a square-root scale. Only the 120 most-read articles are drawn; the journal has 484 in total.

Mint this article as an NFT
Not yet minted

Create a permanent, verifiable on-chain record of this article on the Scimatic Network. The NFT is held in your Journament account, and you can withdraw it to your own wallet at any time.

5 SUSD one-off · no wallet required
Sign in to mint
Abstract
The statistical occurrence of decametre-scale ionospheric irregularities, average line-of-sight (LOS) Doppler velocity, and Doppler spectral width in the sub-auroral, auroral, and polar cap ionosphere ( - 57°L to - 88°L) has been investigated using echoes recorded with the Tasman International Geospace Environment Radar (TIGER), a SuperDARN radar located on Bruny Island, Tasmania (147.2° E, 43.4° S geographic; - 54.6 °L). Results are shown for routine soundings made on the magnetic meridian beam 4 and the near zonal beam 15 during the sunspot maximum interval December 1999 to November 2000. Most echoes were observed in the nightside ionosphere, typically via 1.5-hop propagation near dusk and then via 0.5-hop propagation during pre-midnight to dawn. Peak occurrence rates on beam 4 were often > 60% near magnetic midnight and ~ - 70 °L. They increased and shifted equatorward and toward pre-midnight with increasing Kp (i.e. Bz southward). The occurrence rates remained very high for Kp > 4, de-spite enhanced D-region absorption due to particle precipitation. Average occurrence rates on beam 4 exhibited a relatively weak seasonal variation, consistent with known longitudinal variations in auroral zone magnetic activity (Basu, 1975). The average echo power was greatest between 23 and 07 MLT. Two populations of echoes were identified on both beams, those with low spectral width and a mode value of ~ 9 ms-1 (bin size of 2 ms-1) concentrated in the auroral and sub-auroral ionosphere (population A), and those with high spectral width and a mode value of ~ 70 ms-1 concentrated in the polar cap ionosphere (population B). The occurrence of population A echoes maximised post-midnight because of TIGER’s lower latitude, but the subset of the population A echoes observed near dusk had characteristics reminiscent of "dusk scatter" (Ruohoniemi et al., 1988). There was a dusk "bite out" of large spectral widths between ~ 15 and 21 MLT and poleward of - 67 °L, and a pre-dawn enhancement of large spectral widths between ~  03 and 07 MLT, centred on ~ - 61 °L. The average LOS Doppler velocities revealed that frequent westward jets of plasma flow occurred equatorward of, but overlapping, the diffuse auroral oval in the pre-midnight sector.

Key words. Ionosphere (auroral ionosphere; electric fields and currents, ionospheric irregularities)
Reference Key
parkinson2003annaleson Use this key to autocite in the manuscript while using SciMatic Manuscript Manager or Thesis Manager
Authors ;M. L. Parkinson;J. C. Devlin;H. Ye;C. L. Waters;P. L. Dyson;A. M. Breed;A. M. Breed;R. J. Morris
Journal journal of food measurement and characterization
Year 2003
DOI
10.5194/angeo-21-1847-2003
URL
https://www.ann-geophys.net/21/1847/2003/angeo-21-1847-2003.pdf
Keywords
cosmic physics sciencephysicsgeophysics

Citations

No citations found. To add a citation, contact the admin at info@scimatic.org

Comments

No comments yet. Be the first to comment on this article.