Upper-Atmosphere/Ionosphere Studies with the MU Radar

使用 MU 雷达进行高层大气/电离层研究

• 批准号: 9700162
• 负责人: William Oliver
• 金额: $ 29万
• 依托单位: Trustees of Boston University
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 1997
• 资助国家: 美国
• 起止时间: 1997-04-15 至 2001-03-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=9700162&HistoricalAwards=false
• 关键词: Upper; Atmosphere; Ionosphere; Studies; MU

This project addresses four themes: waves, electric fields, winds and temperatures. The Middle and Upper Atmosphere radar's phased-array construction facilitates the wave work. By observing in multiple directions simultaneously, the PI can distinguish temporal variations over the radar and spatial variations caused by features moving over the radar. He will use this capability to detect gravity-wave propagation over the radar. These waves, almost always present, are best observed in daytime conditions near the peak of the ionosphere. The PI plans to observe waves in the drift velocity in addition to density, study the altitude profile of these waves and their dissipation, and map out their spatial structure. Measurements of electric fields will contribute to developing global electric field models. These electric fields (during solar maximum) show interesting global relationships based on consideration of magnetic conjugacy and summer-hemisphere control of a magnetic field line based on seasonal differences in electrical-conductivity. The PI plans to extend his study to solar minimum, as well as compare data with other radars to test hypotheses made with solar maximum data. MU measurements of thermospheric neutral winds show smaller speeds than do winds at other longitudes. The expanded winds database the PI plans will contribute improvement to current wind models. The PI will also examine this data set for signatures of global wind circulation systems originating from different global processes: direct solar heating, auroral thermal forcing, and equatorial momentum forcing. Finally, he will investigate neutral and ionospheric temperatures, both to develop models of their behavior and to aid in the interpretation of radar Doppler and power data.

该项目涉及四个主题：波浪、电场、风和温度。 中高层大气雷达的相控阵结构有利于波的工作。 通过同时在多个方向上进行观察，PI可以区分雷达上的时间变化和由雷达上移动的特征引起的空间变化。 他将利用这种能力来探测雷达上的引力波传播。 这些波几乎总是存在的，在白天电离层峰值附近的条件下观察得最好。 PI计划除了观测密度外，还观测漂移速度中的波，研究这些波的高度分布及其耗散，并绘制出它们的空间结构。 电场的测量将有助于开发全球电场模型。 基于磁共轭的考虑和基于电导率季节性差异的磁场线的夏季半球控制，这些电场（在太阳活动极大期）显示出有趣的全球关系。 PI计划将他的研究扩展到太阳活动极小期，并将数据与其他雷达进行比较，以测试使用太阳活动极大期数据做出的假设。 MU对热层中性风的测量显示，其风速比其他大气层的风速要小。 PI计划扩展的风数据库将有助于改进当前的风模型。 PI还将检查这一数据集，以确定源自不同全球过程的全球风环流系统的特征：直接太阳加热，极光热强迫和赤道动量强迫。 最后，他将调查中性和电离层温度，既发展其行为的模型，并在雷达多普勒和功率数据的解释帮助。