Japan-US Multi-Instrument Study of Ionospheric Sporadic-E

日美电离层偶发E多仪器研究

基本信息

批准号：
08044074
负责人：
FUKAO Shoichiro
金额：
$ 3.97万
依托单位：
KYOTO UNIVERSITY
依托单位国家：
日本
项目类别：
Grant-in-Aid for international Scientific Research
财政年份：
1996
资助国家：
日本
起止时间：
1996 至无数据
项目状态：
已结题

来源：
https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-08044074/
关键词：
Field-Aligned Irregularity Mid-Latitude Ionosphere Rocket Ground-based Observation Spradic-E layr Radar Observation TMA Neutral Wind Measurement Airglow Imaging Quasi-Periodic Structure

项目摘要

Intense echoes from field-aiegned irregularities are often observed by VHF radars in the mid-latitude ionospheric E-region. In the iregulaties we have found "quasi-periodic (QP)" structures that show intermittent appearance of echoes with periods of 5-10 minutes and with spatial wavelengths of 10-20 km. An observation campaign SEEK (Sporadic-E Exper iment over Kyushu) was conducted successfully for an extensive study of the QP structure conducted in Kyushu, Japan in August 1996. Two sounding rockets were launched from Uchinoura while QP structure was observed by the frequency agile radar (FAR) in Tane-gashima. The sounding rockets observed electric field fluctuations, electron density profiles and fluctuations. Neutral winds were also measured by a TMA (Trimethyl Aluminate) trail. Several ground-based observations were conducted concurrently with the rocket launching, including FAR,MU and Chung-Li/Taiwan VHF radars, MF radar, ionosondes, multicolor imager and Fabry Perot Doppler interferometer. From the TMA experiment, a very large vertical shear in the neutral wind was found near the Es layr. The in-situ electric field strengths exceeded 10 mV/m with large fluctuations at altitudes around 100-120 km. FAR received the most intense echoes around the altitude of the Eslayr, where fluctuations in the electric fields were the maximum. It seems that the irregularities were generated at steep density gradients on both sides of the Es layr.

VHF雷达在纬度电离层E区中经常观察到来自现场AIEGN的不规则的强烈回声。在iregulaties中，我们发现了“准周期性（QP）”结构，这些结构显示出回声的间歇性外观，周期为5-10分钟，空间波长为10-20 km。 1996年8月，成功地进行了一项观察活动（零散的实验），以成功地对日本京胡岛进行的QP结构进行了广泛的研究。从Uchinoura发射了两枚响起的火箭，而QP结构则由Tane-Gashima的频率敏捷雷达（FAR）观察到。发声火箭观察到电场波动，电子密度曲线和波动。还通过TMA（三甲基铝）小径测量中性风。同时进行了几种基于地面的观测，包括FAR，MU和CHUNG-LI/TAIWAN VHF雷达，MF雷达，Ionosondes，Multicolor Imager和Fabry Perot Doppler干涉仪。从TMA实验中，在ES Layr附近发现了中性风中的非常大的垂直剪切。原位电场强度超过10 mV/m，高度约为100-120 km。很远，在Eslayr的高度周围获得了最激烈的回声，在电场中的波动是最大的。看来不规则性是在ES Layr两侧的陡峭密度梯度下产生的。