loading page

The Spontaneous Nature of Lightning Initiation Revealed
  • +5
  • Christopher Sterpka,
  • J Dwyer,
  • N Liu,
  • B M Hare,
  • O Scholten,
  • S Buitink,
  • S Ter Veen,
  • A Nelles
Christopher Sterpka
University of New Hampshire

Corresponding Author:[email protected]

Author Profile
J Dwyer
University of New Hampshire
Author Profile
N Liu
University of New Hampshire
Author Profile
B M Hare
University of Groningen
Author Profile
O Scholten
University of Groningen
Author Profile
S Buitink
Radboud University Nijmegen
Author Profile
S Ter Veen
Netherlands Institute for Radio Astronomy (ASTRON)
Author Profile
A Nelles
Erlangen Center for Astroparticle Physics
Author Profile

Abstract

Here, we present new radio interferometer beamforming observations of lightning initiation using data from the Low Frequency Array (LOFAR). We show that the first lightning source in the flash increases exponentially in intensity by two orders of magnitude in 15 microseconds, while propagating 88 meters away from the initiation location at a constant speed of 4.8 ± 0.1 x 10^6 m/s. A second source replaces the first source at the initiation location, and subsequent propagation of the lightning leader follows. We interpret the first source to be a rapidly propagating and intensifying positive streamer discharge that subsequently produces a hot leader channel near the initiation point. How lightning initiates is one of the greatest unsolved problems in the atmospheric sciences, and these results shed light on this longstanding mystery.
16 Dec 2021Published in Geophysical Research Letters volume 48 issue 23. 10.1029/2021GL095511