【作者】 涂翠；

【导师】 胡雄；

【作者基本信息】 中国科学院研究生院（空间科学与应用研究中心） ， 空间物理学， 2011， 博士

【摘要】 大气重力波是临近空间大气中的基本波动形式之一,在能量和动量传输过程中起到非常重要的作用。全天空大气重力波成像仪是一种以大气气辉辐射为示踪物,能有效对大气重力波成像的仪器。其优点在于:大视场成像;时间分辨率高;空间水平分辨率高;成本低。发展全天空大气重力波成像技术,对于研究大气重力波活动以及大气动力学,提高我国在大气领域的探测能力和相关研究水平具有重要的意义。本文系统研究了全天空大气重力波成像仪基本原理,硬件和软件研制方法,数据预处理方法,应用分析方法。主要内容包括如下几个方面:(1)概要介绍大气重力波与气辉辐射基本理论。在介绍大气结构的基础上侧重介绍大气重力波与气辉辐射基本理论。依据大气重力波线性理论分析了大气重力波对气辉辐射的影响,结果验证了气辉辐射有利于大气重力波观测。(2)详细研究了CSSAR全天空大气重力波成像仪的硬件和软件研制方法。研究了成像仪的基本原理、重点指标计算方法。完成了CSSAR全天空大气重力波成像仪的硬件研制、软件开发。另外总结了软件设计部分关键技术:时间控制和FITS文件存储实现。(3)系统研究了全天空大气重力波成像数据预处理过程。主要包括:去除本底,平场校正、方位校正、畸变校正和星星滤除等。结合CSSAR全天空大气重力波成像仪特征,在畸变校正过程中提出了鱼眼镜头校正环节和方法。(4)中国首次中层顶大气重力波成像观测实验及其数据初步分析结果。实验数据结果显示,当日03:00到05:00点之间,观测到了丰富的、明显的准单色大气重力波水平二维活动。初步分析了3个大气重力波个例,得到它们的水平波长、观测水平相速度、水平传播方位角和观测周期分别约为(12.3 km, 41 m/s, 327°, 5 min), (25 km, 35 m/s, 68°, 12 min)和(10 km, 48 m/s, 341°,3.5 min)。i(5)对一次典型的大气重力波事件开展了综合观测分析。该次事件分析结合使用了中频雷达和TIMED/SABER探测器数据。结果表明,该次事件很可能是由于温度波导导致产生。该次事件中,水平波长随时间递减,递减率约为15.6km/h;传播方位角存在周期性振荡变化,振幅2.5°,振荡周期55分钟,传播方位角振荡平衡位置约为155°。(6) CSSAR全天空大气重力波成像仪观测数据非模糊功率谱和角度谱分析方法研究,并利用该方法对CSSAR全天空大气重力波成像仪2009年1月5日晚观测数据进行了谱分析。谱分析结果清晰地展现该晚观测时间段内所有重力波活动的主要特性:波长下限较短,西向分量明显大于东向分量等。更多还原

【Abstract】 Tracing the airglow emission, all-sky gravity wave imagers are widely used for imaging the atmospheric gravity waves. The characters of the imager are: wide field of view, fast, high resolution, low cost. Until this work, there has never been report researching on this technique in China. Developing the airglow gravity wave imaging technique is significant to the scientific community and prospective to the applied researches in our country.The fundamental principle, the developing technique, the preprocessing procedure, and the analytical method for application of the imager are studied. The main contents can be list as follow:1. The basic theory of the gravity wave and airglow is introduced. Besides the background of the atmosphere, the gravity wave, airglow and their relation are emphasized.2. The developing technique of the hardware and software in the CSSAR gravity wave imager is researched. The basic principle and key parameters are studied, and some key techniques of the hardware and software are concluded.3. The preprocessing method is researched, including the bias correction, flat-field correction, direction correction, distortion correction and star filtering.4. The first imaging observation experiment of the atmospheric gravity waves in the mesopause region in China and the preliminary result are studied. Case studies show that the horizontal wavelengths, observed horizontal phase velocities, horizontal propagation azimuth angles and observed periods of three QMGW examples are about (12.3 km, 41 m/s, 327°, 5 min), (25 km, 35 m/s, 68°, 12 min) and (10 km,48 m/s,341°,3.5 min), respectively.5. A typical gravity wave-event was observed during the CSSAR all-sky gravity wave imager daily observation. The data of the MF radar and TIMED/SABER is co-analyzed and shows that there may be a thermal duct. The wavelength decease at 15.6km/h, and the wave front oscillates around 155°with an amplitude of 2.5°and a period of 55 min.6. The unambiguous power spectrum and angular spectrum are studied, and used for analysis the spectral characters of the gravity waves on Jan. 5th, 2009. The spectral result shows that the low limit of the wavelength is short, and the gravity waves transmit in all directions but more westly than eastly.更多还原