Event Details - Seminar: Radio Interferometry of Lightning

Speaker:  Michael Stock, Earth Networks

Title:  Radio Interferometry of Lightning

Abstract:  When a lightning flash occurs, it produces copious amounts of radio frequency radiation over a broad spectral range.  Multiple, spatially  separated measurements of lightning radio emission  can be combined to locate and map the lightning flash.  Historically, this has been done by measuring the arrival time of the radio emission, and then solving for the source location using triangulation.  These time-of-arrival techniques have been quite successful, and have dramatically broadened our understanding of lightning processes, and climatology.  But there is another way, the radio signals can be combined and correlated against each other using interferometric techniques.  Lightning interferometers have existed and been used in lightning studies since the 70's, but their relative complexity and expense has limited their impact.  In recent years, technological advances in data recorders and computation have made lightning interferometers much more attainable and practical than they were in the past, and has vastly expanded their capabilities as a scientific instrument.  This led to a resurgence of interest in lightning interferometers, and an accompanied advancement of scientific understand of lightning physics.  In this presentation I will discuss the basics of how lightning interferometry works at both high and low frequencies.  Along the way, we'll touch on some cool science, and end with where I think things may be heading in the future.

Bio: Dr. Michael Stock completed his PhD in atmospheric physics at  New Mexico Institute of Mining and Technology in Socorro, New Mexico.  Today he is the principal lightning scientist at Earth Networks where he is responsible for the research and development of all lightning products and services, including the Earth Networks Total Lightning Network (ENTLN), a network of over 1800 lightning sensors distributed around the world.  Dr. Stock has more than 18 years of experience conducting lightning research with projects including balloon born lightning measurements, low frequency observations of lightning in thunderstorms and hurricanes, effects of lightning on shallow mines, radio emission of explosives and rockets, low frequency magnetic measurements of lightning, VHF lightning interferometers, low frequency mapping of lightning flashes, calibration and validation of space base lightning mapping systems, and more.