The Distribution and Source of Plasma Blobs in Low-middle Latitudes

Johns Hopkins University, Baltimore MD

Investigators

Abstract

This is a study to identify the source of plasma blobs (local increases in plasma density) at low and middle latitudes. Specifically, the researchers will address the following science questions: (1) What are the underlying geophysical conditions for the creation of blobs? (2) Are plasma bubbles a prerequisite for the creation of plasma blobs? (3) Are plasma blobs associated with traveling ionospheric disturbances (TIDs)? (4) What is the relationship between blobs and middlelatitude electron density irregularities? Conventional wisdom is that blobs are byproducts of bubbles, but this hypothesis is challenged by the recent observation of blobs in the absence of bubbles in the equatorial region. This project searches for alternative sources of blobs as well as clarifying the causal relationship between bubbles and blobs. Our focused investigation by analyzing various observation data will provide a comprehensive understanding of the characteristics, distribution, and source of blobs that have not yet been fully explored. Recent Communication/Navigation Outage Forecasting System (C/NOFS) satellite observations have provided an unprecedented opportunity to investigate the blob phenomenon with use of ample blob events for several years. In addition, radar, all-sky imager, and other satellite observations are available simultaneously with the C/NOFS observations. The results of this study will advance understanding of the source of the electron density irregularities that are problematic in satellite communication and navigation systems. Case studies will be carried out by using all-sky image data at Arecibo in Puerto Rico, Kototabang in Indonesia, and Bohyun in South Korea to verify the association of blobs with TIDs. The relationship between blobs and middle-latitude irregularities will be determined by examining Korea radar data. Electron density irregularities cause problems in modern technology and are a significant space weather feature that requires global observations to understand their characteristics and predict their occurrence. This project will promote the international collaboration in two aspects: (1) participation of the graduate students in South Korea and Malaysia to the project and (2) utilization of international observation data. Space science is a growing field in those countries, but those countries lack experts in that field. The training and mentoring through this project will support their growth.