Study on electromagnetic environment using EISCAT radar

2010年，利用EISCAT雷达观测和资料，与特罗姆瑟大学合作开展了极地中层和下层热层大气潮汐和重力波行为的研究。1999年3月，该项目利用EISCAT、高频雷达、FAST和GEOTAIL卫星以及地基光学对高纬度极光进行了联合和共轭观测，成功捕获了有趣的亚暴事件。在本项目实施的第2 ~ 10年，利用联合观测资料，深入研究了极帽区极光电动力学，探讨了亚暴的可能机制以及强电弧、电场和场向电流的相关性。对极地中间层区潮汐特征的分析表明，高纬度地区存在日传播潮。对电离层槽形态进行了研究，并对等离子体谱线进行了详细分析。极光层析成像和高频雷达活动与EISCAT雷达一起进行，极光/气辉光谱仪观测已开始与EISCAT雷达密切合作。去年，基于EISCAT雷达资料和1999年8月EISCAT长期资料及其他雷达资料推测非迁移半日潮贡献等大气潮汐全球特征的离子拖曳诱导中性不稳定，随着SOUSY雷达对平流层重力波和湍流的研究以及EISCAT雷达对PMSE数据的分析等合作，引起了人们的关注。通过合作研究，完成了热致气辉的层析重建。还进行了新的流星雷达观测和气辉光谱仪测温，为EISCAT雷达对北极环境研究的协调观测作出贡献。

In the 1^<st> year, a collaborative research work with Univ. Tromso on the atmospheric tide and gravity wave behaviors in the polar mesosphere and lower thermosphere was made by using the EISCAT radar observation and data. In March, 1999 a conjunctive and conjugate observation of high-latitude auroras by EISCAT, HF radars, satellites as FAST and GEOTAIL and ground-based optics was carried out in this project and interesting substorm event was successfully captured. In the 2^<nd> year of this project, an intensive study on the electrodynamics of aurora in the polar cap region was started by using the conjunctive observation data to find out possible mechanisms of substorms and relevance of strong arc, electric field and field-aligned current. An analysis of tidal features in the polar mesospheric regions indicates existence of diurnal propagating tide at higher latitudes. A study on the ionospheric trough morphology and detailed analysis of plasma lines were also made. Auroral tomography and HF radar campaign runs were carried out in conjunction with the EISCAT radar, and auroral/airglow spectrograph observation has started its operation to be in close collaboration with EISCAT radar run. In the last year, ion-drag induced neutral instability based on the EISCAT radar data and global feature of atmospheric tide such as assumed contribution of non-migrating semidiurnal tides by using EISCAT long run data in August, 1999 and other radar data has been put to people's attention along with collaborations on SOUSY radar study of gravity wave and turbulence in the stratosphere and analysis of PMSE data by the EISCAT radar. Tomographic reconstruction of heating-induced airglow was also done through collaborative researches. A new meteor radar observation and temperature measurement by airglow spectrograph have also been undertaken to contribute to the coordinated observation of arctic environmental study by the EISCAT radar.