Preprints
https://doi.org/10.5194/nhess-2021-13
https://doi.org/10.5194/nhess-2021-13

  11 Feb 2021

11 Feb 2021

Review status: a revised version of this preprint is currently under review for the journal NHESS.

Global ground strike point characteristics in negative downward lightning flashes – part 2: Algorithm validation

Dieter R. Poelman1, Wolfgang Schulz2, Stephane Pedeboy3, Leandro Z. S. Campos4, Michihiro Matsui5, Dustin Hill6, Marcelo Saba7, and Hugh Hunt8 Dieter R. Poelman et al.
  • 1Royal Meteorological Institute, Brussels, Belgium
  • 2Austrian Lightning Detection and Information System (ALDIS), Vienna, Austria
  • 3Météorage, Pau, France
  • 4Campos Scientific Computing
  • 5Franklin Japan Corporation, Sagamihara 212-0212, Japan
  • 6Scientific Lightning Solutions LLC (SLS), Titusville, Florida, USA
  • 7National Institute for Space Research, INPE, São José dos Campos, Brazil
  • 8The Johannesburg Lightning Research Laboratory, School of Electrical and Information Engineering, University of Witwatersrand Johannesburg, Johannesburg, South Africa

Abstract. At present the lightning flash density is a key input parameter to assess the risk of occurrence of a lightning strike in a particular region of interest. Since it is known that flashes tend to have more than one ground termination point on average, the use of ground strike point densities as opposed to flash densities is more appropriate. Lightning location systems (LLSs) do not directly provide ground strike point densities. However, ingesting their observations into an algorithm that groups strokes in respective ground strike points results in the sought after density value. The aim of this study is to assess the ability of three distinct ground strike point algorithms to correctly determine the observed ground-truth strike points. The output of the algorithms is tested against a large set of ground-truth observations taken from different regions around the world, including Austria, Brazil, France, Spain, South Africa and the United States of America. These observations are linked to the observations made by local LLSs in order to retrieve the necessary parameters of each lightning discharge and serves as inputs for the algorithms. It follows that all three of the algorithms perform well, with success rates up to about 90 % to retrieve the correct type of the strokes in the flash, i.e., whether the stroke creates a new termination point or follows a pre-existing channel. The most important factor that influences the algorithms' performance is the accuracy by which the strokes are located by the LLS. Additionally, it is shown that the strokes' peak current plays an important role, whereby strokes with a larger absolute peak current have a higher probability of being correctly classified compared to the weaker strokes.

Dieter R. Poelman et al.

Status: final response (author comments only)

Comment types: AC – author | RC – referee | CC – community | EC – editor | CEC – chief editor | : Report abuse
  • RC1: 'Comment on nhess-2021-13', Kenneth Cummins, 14 Mar 2021
  • RC2: 'Comment on nhess-2021-13', Anonymous Referee #2, 28 Mar 2021

Dieter R. Poelman et al.

Dieter R. Poelman et al.

Viewed

Total article views: 304 (including HTML, PDF, and XML)
HTML PDF XML Total BibTeX EndNote
237 56 11 304 0 0
  • HTML: 237
  • PDF: 56
  • XML: 11
  • Total: 304
  • BibTeX: 0
  • EndNote: 0
Views and downloads (calculated since 11 Feb 2021)
Cumulative views and downloads (calculated since 11 Feb 2021)

Viewed (geographical distribution)

Total article views: 279 (including HTML, PDF, and XML) Thereof 279 with geography defined and 0 with unknown origin.
Country # Views %
  • 1
1
 
 
 
 
Latest update: 16 May 2021
Download
Short summary
The lightning flash density is a key input parameter to assess the risk of occurrence of a lightning strike. Flashes tend to have more than one ground termination point on average, therefore the use of ground strike point densities is more appropriate. The aim of this study is to assess the ability of three distinct ground strike point algorithms to correctly determine the observed ground-truth strike points.
Altmetrics