EGU21-10876
https://doi.org/10.5194/egusphere-egu21-10876
EGU General Assembly 2021
© Author(s) 2021. This work is distributed under
the Creative Commons Attribution 4.0 License.

Observations by the LOFAR radio telescope of a fast negative leader propagation mode

Olaf Scholten1 and the LOFAR Lightning and Cosmic ray group*
Olaf Scholten and the LOFAR Lightning and Cosmic ray group
  • 1University of Groningen, Kapteyn Astronomical Institute, physics, Groningen, Netherlands (o.scholten@rug.nl)
  • *A full list of authors appears at the end of the abstract

We report on recent observations made by the LOFAR radio-telescope of a fast propagation mode in negative leaders we named Rapid Negative Leader (RNL).
The RNL has a variety of properties that make them clearly distinct from negative leaders or dart leaders, such as -- fast propagation, -- emission of strong broad-band pulses, -- emission of very high VHF power, -- a reduced density of located sources, and -- terminating with the spawning of a large number of negative leaders in a small area. RNLs are almost always observed in the initial stage of a lightning flash, but may also occur much later. They may occur repeatedly in a certain part of the cloud.

We interpret a RNL as negative leader developing in strong electric field due to a relatively small highly-charged cloud, probably created by a local turbulence, with a typical size of order 5 km2.  The strong field will lead to a larger than usual charge at the leader tip resulting in an increased propagation velocity as well as a strongly enhanced emission of VHF power.
Since for the initiation of a lightning flash strong ambient electric fields are required, it is thus no surprise that the initial leader is in fact a RNL. 

What do you want to do ?
New mail
What do you want to do ?
New mail
LOFAR Lightning and Cosmic ray group:

O.Scholten, B.M.Hare, J.Dwyer, N.Liu, C.Sterpka, I.Kolmatsova, O.Santol, R.Lan, L.Uhlir, S.Buiting, A.Corstanje, H.Falcke, T.Huege, J.R.H.Hoerandel, G.K.Krampah, P.Mitra, K.Mulrey, A.Nelles, H.Pandya, J.P.Rachen, T.N.G.Trinh, S.terVeen, S.Thoudam, T.Winchen

How to cite: Scholten, O. and the LOFAR Lightning and Cosmic ray group: Observations by the LOFAR radio telescope of a fast negative leader propagation mode, EGU General Assembly 2021, online, 19–30 Apr 2021, EGU21-10876, https://doi.org/10.5194/egusphere-egu21-10876, 2021.

Display materials

Display file

Comments on the display material

to access the discussion