Collaborative Research: Common Volume Radar Observations of Irregular Sporadic E Layers

这是一个为期4年的项目，目的是利用阿雷西博非相干散射雷达、它的仪器群和一个将部署在圣克罗伊岛维尔京群岛大学（UVI）附近的新相干散射成像雷达，研究中纬度零星E层、不规则层和所谓的准周期（QP）回波。2002年夏季进行的一项初步研究表明，QP回波来自于以前在阿雷西博观测到的那种零星E层中的细长波状结构，并初步与中性切变不稳定性驱动的对流有关。圣克罗伊的新自主雷达将与阿雷西博设施一起进行长期远程观测，以评估中性中间层-低层热层（MLT）区域的稳定性，确定层结构的真正原因，并研究产生QP回波的等离子体物理。零星的E层和不规则性极大地影响高频和甚高频无线电波的传播，因此该项目也与空间天气有关。该项目将把高层大气研究的教育经验带给弗吉尼亚大学多样化的本科生群体，以及康奈尔大学和克莱姆森大学的研究生。此外，圣克罗伊岛的成像雷达将成为阿雷西博设施的一部分，并增加非相干散射雷达和光学仪器的能力。它将为阿雷西博天文台的仪器群增加相干散射能力，供社区研究零星E，中纬度传播F，流星回波以及其他普遍感兴趣的主题。这是一个由来自康奈尔大学、克莱姆森大学和弗吉尼亚大学的共同研究人员和学生参与的多机构提案。

This is a 4-year project to investigate mid-latitude sporadic E layers, layer irregularities, and so-called quasi-periodic (QP) echoes using the Arecibo incoherent scatter radar, its instrument cluster, and a new coherent scatter imaging radar to be deployed near the University of the Virgin Islands (UVI) on St. Croix. A pilot study was carried out during the summer of 2002 which showed that the QP echoes arose from elongated, wavelike structures in sporadic E layers of the kind that has previously been observed at Arecibo and tentatively been associated with convection driven by neutral shear instabilities. Long-term, remote observations by the new autonomous radar in St. Croix will be used together with the Arecibo facility to assess the stability of the neutral mesosphere-lower-thermosphere (MLT) region, identifying the true cause of the layer structuring, and studying the plasma physics involved in producing the QP echoes. Sporadic E layers and irregularities drastically affect HF and VHF radio wave propagation so the project also has space weather relevance. The project will bring educational experiences in upper atmospheric research to the diverse undergraduate student body at UVI, as well as to graduate students at Cornell and Clemson University. Furthermore, the imaging radar on St. Croix will become part of the Arecibo facility and add to the capabilities of the Incoherent Scatter Radar and optical instrumentation. It will add coherent scatter capabilities to the Arecibo Observatory instrument cluster, accessible by the community for studies of sporadic E, mid-latitude spread F, and meteor echoes, among other topics of general interest. This is a multi-institution proposal with co-investigators and students from Cornell, Clemson, and UVI participating.