Our latest peer-reviewed journal paper “Optical Observations of Needles in Upward Lightning Flashes” was published on 15 Oct 2020. It is open access and available for download at the link below.

Paper download

The paper describes how attempted branches on positive leader channels can pulse well after the leader tip continues propagating away. These pulsing features are defined as “needles” and in rare cases, they can develop into a negative leader branch.

Figure showing a pulsing needle on a positive leader channel that develops into a negative leader branch

The online version of the paper which includes supplementary video can be found at this link.

Saba, M.M.F., A. R. de Paiva, L. C. Concollato, T. A. Warner and C. Schumann (2020), Optical observation of needles in upward lightning flashes. Sci Rep 10, 17460 (2020) doi:10.1038/s41598-020-74597-6