Low-cost GNSS-based Space Weather Monitors: Development Deployment, and Scientific Applications

Abstract

This dissertation describes results of efforts related to the development, deployment and scientific applications of a low-cost ionospheric scintillation and total electron content (TEC) monitor. These efforts were motivated by the problem of the relatively high cost of specialized commercial ionospheric scintillation and TEC monitors. They were also motivated by recent reports about the occurrence of large ionospheric disturbances at middle latitudes, challenging the space science community to monitor scintillation activity over this region. Prior to these reports, the occurrence of significant ionospheric disturbances were thought to be limited to low and high latitudes. Measurements of ionospheric scintillation and TEC allow advances in our understanding of the space environment near-Earth (geospace). This includes the fundamental physical processes driving ionospheric variability that are associated with solar and geomagnetic activity. The study of scintillation and TEC is also motivated by challenges imposed on the performance of Global Navigation Satellite Systems (GNSS). Chapter 1 of this dissertation provides a brief description of ionospheric effects on radio signals and how these effects can be used for remote sensing the Earth’s ionosphere. Chapter 2 describes and discusses the development of a novel GNSS-based ionospheric scintillation and TEC monitors (ScintPi 2.0 and 3.0) that are not only low cost but also easy to deploy and maintain. The description is accompanied by a discussion of measurements of low latitude scintillation and TEC depletions associated with the so-called equatorial plasma bubbles (EPBs). The ScintPi measurements are compared with collocated observations made by a commercial monitor (Septentrio PolaRx5S). Chapter 3 extends the ScintPi’s application to unprecedent observations of scintillation at low-to-mid latitudes during geomagnetically quiet conditions, while Chapter 4 presents and discusses the application of ScintPi in the observation of a low-to-mid latitude severe scintillation event triggered by a geomagnetic storm. Chapter 5 expands ScintPi measurements in studies of ionospheric irregularity drifts at low latitudes. Chapter 6 reveals, for the first time, the occurrence of extraordinary scintillation events simultaneously detected by ScintPi monitors distributed across low to mid latitudes. Finally, Chapter 7 summarizes the main results, highlights the dissertation contributions, and provides suggestions for future work