基于海南VHF雷达观测的低纬E区场向不规则体研究

尚社平; 史建魁; 阎敬业; 杨国涛; 王霄; 燕春晓; 王继红; 吴琼之; 南方

doi:10.11728/cjss2014.01.053

基于海南VHF雷达观测的低纬E区场向不规则体研究

doi: 10.11728/cjss2014.01.053

1.
中国科学院空间科学与应用研究中心空间天气学国家重点实验室北京 100190
2.
中国科学院空间科学与应用研究中心微波遥感技术重点实验室北京 100190
3.
北京理工大学信息与电子学院北京 100081

基金项目: 国家自然科学基金项目（40890164，40874083）；国家重点实验室专项基金项目共同资助

详细信息

通讯作者:
尚社平,E-mail:shangsp@nssc.ac.cn

中图分类号: P353
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出版历程
- 收稿日期: 2013-02-01
- 修回日期: 2013-07-21
- 刊出日期: 2014-01-15

Investigations of low latitude E region field-aligned irregularities with Hainan VHF radar

1.
State Key Laboratory of Space Weather, Center for Space Science and Applied Research, Chinese Academy of Sciences, Beijing 100190
2.
Key Laboratory of Microwave Remote Sensing, Center for Space Science and Applied Research, Chinese Academy of Sciences, Beijing 100190
3.
School of Information and Electronics, Beijing Institute of Technology, Beijing 100081

摘要

摘要: 利用海南VHF雷达（19.5°N，109.1°E；磁纬8.1°N）在2011年7月15—22日期间的连续观测数据，对东亚低纬3m尺度电离层场向不规则体（FAI）特性进行了分析. 主要结果表明，在整个观测期间，E区场向不规则体几乎每天发生，既可发生于夜间，也可发生于白天，且存在各种不同结构. 根据E区场向不规则体发生的时间及形态，可将其分为三种结构类型：低部连续型结构、上部下降型结构以及白天连续型结构. 这些低纬E区场向不规则体的回波谱特性与赤道电集流（EEJ）和中纬区E区场向不规则体中的2型回波相类似，但其随时间的变化与后两者存在明显差异，且与其他低纬区E区场向不规则体回波存在不同程度的差异.
- 东亚低纬区 /
- 海南VHF雷达 /
- E区场向不规则体
Abstract: Using the continuous observation data of Hainan VHF radar (19.5°N, 109.1°E; dip latitude 8.1°N) on July 15—22, 2011, the characteristics of 3m scale Field-Aligned ionospheric Irregularities (FAI) in Eastern Asia low latitude are analyzed. The main results show the E region FAI echoes almost occur everyday during the whole observation period. They can occur both in day and night and have different complicated structures. According to their occurrence time and structure, the E region FAI echoes can be classified into the following three cases. First is the lower continuous echoes, which mainly occur from the later afternoon to pre-midnight (17:30LT—23:00LT) with evident enhanced echo intensity and negative (downward/southward) Doppler velocities. The second is the upper descend layer structures, which mainly appear from nearly midnight to pre-sunrise (23:00LT°05:00LT) with more enhanced echo intensity and both positive and negative Doppler velocities, where the positive Doppler velocities (upward/northward) dominate in the upper E region echoes. The third is the daytime continuous echoes, which mainly occur from morning to nearly noontime (07:00LT—11:30LT) with reduced echo intensity and both positive and negative Doppler velocities. These low latitude E region echoes mainly are type-I!I, which is similar to that of the Equatorial Electrojet (EEJ) and mid-latitude regions, but their temporal behavior is evidently different from that of the latter two latitudes and also has some differences with that of the other low latitudes.
- Eastern Asia low latitude region /
- Hainan VHF radar /
- E region Field-Aligned Irregularities (FAI)

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