High altitude large-scale plasma waves in the equatorial electrojet at twilight
Jicamarca radar observations of a new class of large-scale plasma waves in the equatorial electrojet (EEJ) are presented and characterized. The study is based on long-term (204 days), single-baseline interferometry observations made in 2003 using a low-power radar mode, also known as J...
| Main Authors: | , |
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| Format: | Article |
| Language: | English |
| Published: |
Copernicus Publications
2004-12-01
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| Series: | Annales Geophysicae |
| Online Access: | https://www.ann-geophys.net/22/4071/2004/angeo-22-4071-2004.pdf |
| _version_ | 1818245394622054400 |
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| author | J. L. Chau D. L. Hysell |
| author_facet | J. L. Chau D. L. Hysell |
| author_sort | J. L. Chau |
| collection | DOAJ |
| description | Jicamarca radar observations of a new class of large-scale plasma
waves in the equatorial electrojet (EEJ) are presented and
characterized. The study is based on long-term (204 days),
single-baseline interferometry observations made in 2003 using a
low-power radar mode, also known as JULIA mode, along with a few
hours of observations made in an aperture synthesis imaging mode.
The large-scale waves are found to occur at high altitudes in the
E-region, mainly between 120 and 140km, around twilight
(between 18:30 and 20:00 LT), with durations of a few minutes to an
hour. In our long-term observations, these large-scale waves occur
very often (between 1 and 5 out 10 nights), drift westward
(~70 ms<sup>–1</sup>), exhibit very narrow spectral widths, and have
both positive and negative Doppler shifts. The imaging results
show that the large-scale waves occur along tilted bands that
sweep westward and downward (~30–60ms<sup>–1</sup>), with a horizontal
separation between bands of about 10–15km. The cause of the
waves remains unknown.
<br><br><b>Key words.</b> Ionosphere (ionospheric irregularities; equatorial
ionosphere; instruments and techniques) |
| first_indexed | 2024-12-12T14:32:13Z |
| format | Article |
| id | doaj.art-c92ffd9c527c46cebb9b20eeee9552f5 |
| institution | Directory Open Access Journal |
| issn | 0992-7689 1432-0576 |
| language | English |
| last_indexed | 2024-12-12T14:32:13Z |
| publishDate | 2004-12-01 |
| publisher | Copernicus Publications |
| record_format | Article |
| series | Annales Geophysicae |
| spelling | doaj.art-c92ffd9c527c46cebb9b20eeee9552f52022-12-22T00:21:29ZengCopernicus PublicationsAnnales Geophysicae0992-76891432-05762004-12-01224071407610.5194/angeo-22-4071-2004High altitude large-scale plasma waves in the equatorial electrojet at twilightJ. L. Chau0D. L. Hysell1Radio Observatorio de Jicamarca, Instituto Geofísico del Perú, Lima, PeruDepartment of Earth and Atmospheric Sciences, Cornell University, Ithaca, New York, USAJicamarca radar observations of a new class of large-scale plasma waves in the equatorial electrojet (EEJ) are presented and characterized. The study is based on long-term (204 days), single-baseline interferometry observations made in 2003 using a low-power radar mode, also known as JULIA mode, along with a few hours of observations made in an aperture synthesis imaging mode. The large-scale waves are found to occur at high altitudes in the E-region, mainly between 120 and 140km, around twilight (between 18:30 and 20:00 LT), with durations of a few minutes to an hour. In our long-term observations, these large-scale waves occur very often (between 1 and 5 out 10 nights), drift westward (~70 ms<sup>–1</sup>), exhibit very narrow spectral widths, and have both positive and negative Doppler shifts. The imaging results show that the large-scale waves occur along tilted bands that sweep westward and downward (~30–60ms<sup>–1</sup>), with a horizontal separation between bands of about 10–15km. The cause of the waves remains unknown. <br><br><b>Key words.</b> Ionosphere (ionospheric irregularities; equatorial ionosphere; instruments and techniques)https://www.ann-geophys.net/22/4071/2004/angeo-22-4071-2004.pdf |
| spellingShingle | J. L. Chau D. L. Hysell High altitude large-scale plasma waves in the equatorial electrojet at twilight Annales Geophysicae |
| title | High altitude large-scale plasma waves in the equatorial electrojet at twilight |
| title_full | High altitude large-scale plasma waves in the equatorial electrojet at twilight |
| title_fullStr | High altitude large-scale plasma waves in the equatorial electrojet at twilight |
| title_full_unstemmed | High altitude large-scale plasma waves in the equatorial electrojet at twilight |
| title_short | High altitude large-scale plasma waves in the equatorial electrojet at twilight |
| title_sort | high altitude large scale plasma waves in the equatorial electrojet at twilight |
| url | https://www.ann-geophys.net/22/4071/2004/angeo-22-4071-2004.pdf |
| work_keys_str_mv | AT jlchau highaltitudelargescaleplasmawavesintheequatorialelectrojetattwilight AT dlhysell highaltitudelargescaleplasmawavesintheequatorialelectrojetattwilight |