The First Report on the Afternoon E -Region Plasma Density Irregularities in Middle Latitude
We report, for the first time, the afternoon (i.e., from noon to sunset time) observations of the northern mid-latitude E-region field-aligned irregularities (FAIs) made by the very high frequency (VHF) coherent backscatter radar operated continuously since 29 December 2009 at Daejeon (36.18°N, 12...
| Main Authors: | , , , , |
|---|---|
| Format: | Article |
| Language: | English |
| Published: |
The Korean Space Science Society
2021-06-01
|
| Series: | Journal of Astronomy and Space Sciences |
| Subjects: | |
| Online Access: | http://koreascience.or.kr/article/JAKO202118248972703.page |
| _version_ | 1797329921533542400 |
|---|---|
| author | Tae-Yong Yang Young-Sil Kwak Jaeheung Park Seonghwan Choi Jaewook Lee |
| author_facet | Tae-Yong Yang Young-Sil Kwak Jaeheung Park Seonghwan Choi Jaewook Lee |
| author_sort | Tae-Yong Yang |
| collection | DOAJ |
| description | We report, for the first time, the afternoon (i.e., from noon to sunset time) observations of the northern mid-latitude E-region
field-aligned irregularities (FAIs) made by the very high frequency (VHF) coherent backscatter radar operated continuously
since 29 December 2009 at Daejeon (36.18°N, 127.14°E, 26.7°N dip latitude) in South Korea. We present the statistical
characteristics of the mid-latitude afternoon E-region FAIs based on the continuous radar observations. Echo signal-to-noise
ratio (SNR) of the afternoon E-region FAIs is found to be as high as 35 dB, mostly occurring around 100–135 km altitudes.
Most spectral widths of the afternoon echoes are close to zero, indicating that the irregularities during the afternoon time are
not related to turbulent plasma motions. The occurrence of afternoon E-regional FAI is observed with significant seasonal
variation, with a maximum in summer and a minimum in winter. Furthermore, to investigate the afternoon E-region FAIs-
Sporadic E (Es) relationship, the FAIs have also been compared with Es parameters based on observations made from an
ionosonde located at Icheon (37.14°N, 127.54°E, 27.7°N dip latitude), which is 100 km north of Daejeon. The virtual height of
Es (h’Es) is mainly in the height range of 105 km to 110 km, which is 5 km to 10 km greater than the bottom of the FAI. There is
no relationship between the FAI SNR and the highest frequencies (ftEs) (or blanket frequencies (fbEs)). SNR of FAIs, however, is
found to be related well with (ftEs–fbEs). |
| first_indexed | 2024-03-08T07:12:20Z |
| format | Article |
| id | doaj.art-24d88d67c4694b9bb6f50cf1bd8942c2 |
| institution | Directory Open Access Journal |
| issn | 2093-5587 2093-1409 |
| language | English |
| last_indexed | 2024-03-08T07:12:20Z |
| publishDate | 2021-06-01 |
| publisher | The Korean Space Science Society |
| record_format | Article |
| series | Journal of Astronomy and Space Sciences |
| spelling | doaj.art-24d88d67c4694b9bb6f50cf1bd8942c22024-02-03T02:10:51ZengThe Korean Space Science SocietyJournal of Astronomy and Space Sciences2093-55872093-14092021-06-0138213514310.5140/JASS.2021.38.2.135The First Report on the Afternoon E -Region Plasma Density Irregularities in Middle LatitudeTae-Yong Yang0https://orcid.org/0000-0002-5725-9828Young-Sil Kwak1https://orcid.org/0000-0003-3375-8574Jaeheung Park2https://orcid.org/0000-0002-1272-508XSeonghwan Choi3https://orcid.org/0000-0002-1946-7327Jaewook Lee4https://orcid.org/0000-0002-5284-4841Korea Astronomy and Space Science Institute, Daejeon 34055, KoreaKorea Astronomy and Space Science Institute, Daejeon 34055, KoreaKorea Astronomy and Space Science Institute, Daejeon 34055, KoreaKorea Astronomy and Space Science Institute, Daejeon 34055, KoreaKorea Astronomy and Space Science Institute, Daejeon 34055, KoreaWe report, for the first time, the afternoon (i.e., from noon to sunset time) observations of the northern mid-latitude E-region field-aligned irregularities (FAIs) made by the very high frequency (VHF) coherent backscatter radar operated continuously since 29 December 2009 at Daejeon (36.18°N, 127.14°E, 26.7°N dip latitude) in South Korea. We present the statistical characteristics of the mid-latitude afternoon E-region FAIs based on the continuous radar observations. Echo signal-to-noise ratio (SNR) of the afternoon E-region FAIs is found to be as high as 35 dB, mostly occurring around 100–135 km altitudes. Most spectral widths of the afternoon echoes are close to zero, indicating that the irregularities during the afternoon time are not related to turbulent plasma motions. The occurrence of afternoon E-regional FAI is observed with significant seasonal variation, with a maximum in summer and a minimum in winter. Furthermore, to investigate the afternoon E-region FAIs- Sporadic E (Es) relationship, the FAIs have also been compared with Es parameters based on observations made from an ionosonde located at Icheon (37.14°N, 127.54°E, 27.7°N dip latitude), which is 100 km north of Daejeon. The virtual height of Es (h’Es) is mainly in the height range of 105 km to 110 km, which is 5 km to 10 km greater than the bottom of the FAI. There is no relationship between the FAI SNR and the highest frequencies (ftEs) (or blanket frequencies (fbEs)). SNR of FAIs, however, is found to be related well with (ftEs–fbEs).http://koreascience.or.kr/article/JAKO202118248972703.pagevery high frequency (vhf) coherent backscatter radarafternoon e-region irregularities |
| spellingShingle | Tae-Yong Yang Young-Sil Kwak Jaeheung Park Seonghwan Choi Jaewook Lee The First Report on the Afternoon E -Region Plasma Density Irregularities in Middle Latitude Journal of Astronomy and Space Sciences very high frequency (vhf) coherent backscatter radar afternoon e-region irregularities |
| title | The First Report on the Afternoon E -Region Plasma Density Irregularities in Middle Latitude |
| title_full | The First Report on the Afternoon E -Region Plasma Density Irregularities in Middle Latitude |
| title_fullStr | The First Report on the Afternoon E -Region Plasma Density Irregularities in Middle Latitude |
| title_full_unstemmed | The First Report on the Afternoon E -Region Plasma Density Irregularities in Middle Latitude |
| title_short | The First Report on the Afternoon E -Region Plasma Density Irregularities in Middle Latitude |
| title_sort | first report on the afternoon e region plasma density irregularities in middle latitude |
| topic | very high frequency (vhf) coherent backscatter radar afternoon e-region irregularities |
| url | http://koreascience.or.kr/article/JAKO202118248972703.page |
| work_keys_str_mv | AT taeyongyang thefirstreportontheafternooneregionplasmadensityirregularitiesinmiddlelatitude AT youngsilkwak thefirstreportontheafternooneregionplasmadensityirregularitiesinmiddlelatitude AT jaeheungpark thefirstreportontheafternooneregionplasmadensityirregularitiesinmiddlelatitude AT seonghwanchoi thefirstreportontheafternooneregionplasmadensityirregularitiesinmiddlelatitude AT jaewooklee thefirstreportontheafternooneregionplasmadensityirregularitiesinmiddlelatitude AT taeyongyang firstreportontheafternooneregionplasmadensityirregularitiesinmiddlelatitude AT youngsilkwak firstreportontheafternooneregionplasmadensityirregularitiesinmiddlelatitude AT jaeheungpark firstreportontheafternooneregionplasmadensityirregularitiesinmiddlelatitude AT seonghwanchoi firstreportontheafternooneregionplasmadensityirregularitiesinmiddlelatitude AT jaewooklee firstreportontheafternooneregionplasmadensityirregularitiesinmiddlelatitude |