Alanah Cardenas-O’Toole, a graduate student at U-M Climate & Space, has been selected to receive the highly competitive Future Investigators in NASA Earth and Space Science and Technology fellowship.
As part of the FINESST fellowship, NASA has awarded $150,000 to fund Cardenas-O’Toole’s proposal “EA-EPB: a Statistical and Event Analysis of super Equatorial Plasma Bubbles.” Out of the 927 proposals received, NASA’s Heliophysics Division reviewed 60 proposals, and the Science Mission Directorate selected only 14 proposals for awards. Cardenas-O’Toole’s faculty advisor is Associate Professor Shasha Zou, Ph.D.
Equatorial Plasma Bubbles (EPBs) are one of the most severe space weather phenomena that occur in the ionosphere causing high levels of radio scintillation, which can degrade Global Navigation Satellite System (GNSS) signals. Due to the increasing use of satellite communication and navigation technology, it is essential to understand the characteristics and space weather impact of EPBs in order to better predict future EPBs occurrence and mitigate their impact. Recently, EPBs have been suggested to be able to extend towards midlatitudes and called ‘Super EPBs’; these have the potential to cause major GNSS problems at the midlatitudes, such as deep into the U.S., which are not generally plagued with high scintillation levels. Due to the potential harm that these Super EPBs could cause, we propose to identify the rate of occurrence, characterize their properties and evaluate their potential scintillation impact of the Super EPBs.
In this proposal, the goal is to answer the following questions:
1) How often do Super EPBs occur?
2) Under what solar and geomagnetic conditions do Super EPBs form?
3) How severe are the Super EPBs caused scintillations in the midlatitudes?
The research team will perform a comprehensive multi-instrument data analysis, such as SWARM in-situ density data, VISTA TEC, and NASA GOLD mission data. They will use the EPB index provided by SWARM satellites, analyze the occurrence rate of the Super EPBs (~>20 magnetic latitude) and focus on the large-scale background and geomagnetic activity conditions of Super EPBs to improve our understanding of when and where they tend to occur. The TEC and GOLD data will be utilized to provide the large-scale context of the ionosphere during the Super EPB events. They will then evaluate the scintillations due to these Super EPBs by analyzing the rate-of-density (ROD) and rate-of-TEC (ROT).
The proposed study is highly relevant to one of NASA’s objectives in the 2014 NASA Strategic Plan. Objective 1.4 states ‘Understand the Sun and its interactions with Earth and the solar system, including space weather.’ Additionally, the proposal is relevant to the key objectives of the most recent decadal survey ‘Advance our understanding of the Sun’s activity, and the connections between solar variability and Earth and planetary space environments, the outer reaches of our solar system, and the interstellar medium.’ This proposal would help our society be better prepared for the potential GNSS complications that can arise from Super EPBs migrating towards midlatitudes, particularly deep in the U.S.