Study on electromagnetic environment using EISCAT radar

在1^lt；st&gt；年，与大学的合作研究工作。利用EISCAT雷达观测和资料，对极地中间层和低热层的大气潮汐和重力波行为进行了数值模拟。1999年3月，利用EISCAT、高频雷达、ASFAST卫星、GEOTAIL和地面光学系统对高纬度极光进行了联合和共轭观测，成功地捕捉到了有趣的亚暴事件。在该项目的第二年，利用联合观测数据开始了对极冠地区极光电动力学的深入研究，以找出可能的亚暴机制以及强弧光、电场和场向电流的相关性。对极地中间层潮汐特征的分析表明，在高纬度地区存在日间传播潮汐。对电离层槽形进行了研究，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运行是与EISCAT雷达联合进行的，极光/气辉光谱仪观测已经开始运作，以便与EISCAT雷达运行密切合作。在过去的一年里，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资料的分析，基于EISCAT雷达资料和全球大气潮汐特征的离子拖曳引起的中性不稳定引起了人们的关注，如利用1999年8月EISCAT长期资料和其他雷达资料假设非迁移性半日潮的贡献。通过合作研究，还对加热诱导的气辉进行了层析重建。还开展了一项新的流星雷达观测和用气辉光谱仪测量温度，以促进EISCAT雷达对北极环境研究的协调观测。

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.