Collaborative Research: CEDAR--Experimental and Theoretical Investigation of Midlatitude Ionospheric Instability

这项研究解决了关于地球电离层中的空间天气现象的长期存在的问题，这种现象可能会对高频和甚高频通信产生严重影响。人们对这些现象的特点和原因仍知之甚少。该项目有三个主要组成部分：(1)电离层不规则性和不稳定性的数值模拟和建模；(2)使用康奈尔大学和克莱姆森大学以及米尔斯通山观测站部署的便携式相干散射雷达进行的实验观测；(3)阿雷西博观测站的非相干散射雷达观测，并辅之以瓜德罗普岛的相干散射实验(使用将作为该项目的一部分安装的雷达)。这项工作的更广泛的影响是通过它在理解空间天气方面的应用，以及通过确保两所大学的学生广泛参与的强大的教育组成部分。大气学调查的重点是电离层现象，包括零星的E层(ES)、中等尺度的移动电离层扰动(MSTID)和与中纬度扩展F条件(MSF)相关的等离子体不规则。该项目研究了中性/等离子体和E区/F区在共同物理环境中的耦合。主要目标涉及1)中纬电离层等离子体不稳定的性质，2)中性大气动力学在MSF发生中的作用，3)E区和F区之间耦合的性质，4)这些现象如何随纬度变化。通过将地面观测扩展到整个北美，研究人员将研究E区和F区等离子体的不规则性和不稳定性是如何因果相关的。将开发一个新的地区性中性/等离子体耦合动力学模型，这将使我们能够超越理想化的理论方法，深入了解中纬度的空间天气。更广泛的影响不仅是通过空间气象的应用，也是通过康奈尔大学和克莱姆森大学为本科生和研究生提供的教育机会。这一奖项反映了NSF的法定使命，并通过使用基金会的智力优势和更广泛的影响审查标准进行评估，被认为值得支持。

This research addresses long standing questions about space-weather phenomena in Earth's ionosphere, which can have drastic effects including on HF and VHF communications. The characteristics and causes of these phenomena remain poorly understood. The project has three main components: (i) numerical simulations and modeling of ionospheric irregularities and instabilities, (ii) experimental observations made with portable coherent scatter radar deployed by Cornell University and Clemson University as well as the Millstone Hill Observatory, and (iii) incoherent scatter radar observations at the Arecibo Observatory complemented by coherent scatter experiments from the island of Guadeloupe (using a radar to be installed as part of this project). The broader impacts of this work are through its applications to understanding space weather and via a strong educational component that assures extensive involvement of students at both universities.The aeronomy investigations focus on ionospheric phenomena including sporadic E layers (Es), medium-scale traveling ionospheric disturbances (MSTID), and plasma irregularities associated with mid-latitude spread-F conditions (MSF). The project examines both neutral/plasma and E region/F region coupling in a common physical context. The main goals pertain to 1) the nature of the plasma instabilities in the mid-latitude ionosphere, 2) the role of neutral atmosphere dynamics in the occurrence of MSF, 3) the nature of the coupling between the E and F regions, and 4) how these phenomena vary with latitude. By extending ground-based observations across North America, the researchers will study how E- and F-region plasma irregularities and instabilities are causally related. A new regional, coupled neutral/plasma dynamics model will be developed, which will allow going beyond idealized theoretical approaches toward a deeper understanding of space weather at middle latitudes. The broader impacts are through not only the applications to space weather but also the educational opportunities at Cornell University and Clemson University for undergraduate and graduate students.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.