Collaborative Research: Antarctic ELF/VLF Observations of Q-bursts, Radio Atmospherics, and Energetic Particle Precipitation

Stanford University, Stanford CA

Investigators

Abstract

The overarching goal of this award is to quantitatively investigate lightning and energetic particle precipitation from the Earth?s radiation belts using the extremely and very low frequency (ELF/VLF, ~5 Hz?32 kHz) observations on the Antarctic continent. A coordinated effort will fully characterize individual lightning return strokes occurring in the Northern hemisphere while simultaneously observing the associated ELF/VLF radio atmospheric (sferic) in the Antarctic (and other global locations). A special effort will focus on a class of large-amplitude ELF sferics known as Q-bursts in order to quantify global ionospheric conditions and the characteristics of the causative lightning flash. Narrowband VLF observations of lightning-induced electron precipitation (LEP) will be simultaneously conducted in the Northern and Southern hemispheres in order to validate a new LEP model that accounts for the lightning current waveform and return stroke speed. Furthermore, this program critically evaluates whether rocket-triggered lightning may be detected in the Antarctic, allowing for controlled broadband ELF/VLF propagation studies, and whether it may produce LEP in the conjugate hemisphere. The broader impacts of this award are in identifying direct effects of space weather events for the studies by atmospheric and space electricity research communities. The project introduces a new platform from which to conduct controlled lightning-related ELF/VLF experiments using rocket-triggered lightning in Florida, it provides real-time access to experimental observations via the Internet, and it exposes the program to youths through the operation of VLF receivers at high schools in the United States. The dissemination of program results also takes the form of refereed journal publications and conference presentations. The project will train graduate students with the development and operation of the deployed instruments, as well as with space weather science investigations. Use of these data to validate space weather models can provide benefit to society as a whole.