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Relativistic electron beams above thunderclouds

Profile image of Olivier ChanrionOlivier ChanrionProfile image of Robert Roussel-DupreRobert Roussel-Dupre

2011, Atmospheric Chemistry and Physics

https://doi.org/10.5194/ACP-11-7747-2011
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22 pages

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Abstract

Non-luminous relativistic electron beams above thunderclouds are detected by radio remote sensing with low frequency radio signals from ∼40-400 kHz. The electron beams occur ∼2-9 ms after positive cloud-to-ground lightning discharges at heights between ∼22-72 km above thunderclouds. The positive lightning discharges also cause 5 sprites which occur either above or before the electron beam. One electron beam was detected without any luminous sprite occurrence which suggests that electron beams may also occur independently. Numerical simulations show that the beamed electrons partially discharge the lightning electric field above thunderclouds and thereby gain a mean energy of ∼7 MeV to transport a total charge of ∼10 mC upwards. The impul-10 sive current associated with relativistic electron beams above thunderclouds is directed downwards and needs to be considered as a novel element of the global atmospheric electric circuit. ulation of energetic seed particles to initiate an electromagnetically radiating non-linear 15553 ACPD Abstract Relativistic electron beams M. Füllekrug et al. Title Page Abstract Relativistic electron beams M. Füllekrug et al. Title Page Abstract Relativistic electron beams M. Füllekrug et al. Title Page Abstract Relativistic electron beams M. Füllekrug et al.

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