Positive lightning peak currents reported by the U.S. national lightning detection network

Amitabh Nag, Vladimir A. Rakov, Kenneth L. Cummins

Research output: Contribution to journalArticlepeer-review

15 Scopus citations


We infer peak currents from radiation electric field peaks of 48 positive return strokes acquired in Gainesville, FL, USA, from 2007 to 2008. In doing so, we use the transmission line model, National Lightning Detection Network (NLDN)-reported distances, and assumed return-stroke speed. From a similar analysis of negative subsequent strokes, it appears that the implied return-stroke speed in the NLDN field-to-current conversion equation is 1.8 × 108 m/s (the NLDN peak current estimation algorithm is calibrated for negative subsequent strokes). The NLDN uses the same field-to-current conversion procedure (and hence the same implied return-stroke speed) for positive return strokes. However, NLDN-reported peak currents for positive return strokes differ from peak currents predicted by the transmission line model with an assumed return-stroke speed of 1.8 × 108 m/s. The discrepancy between regression equations for negative and positive return strokes suggests that the NLDN procedure to compensate for field propagation effects and find the average range-normalized signal strength (RNSS) works differently for these two groups of strokes. We find that the difference can be explained by the bias toward NLDN sensor reports from larger distances for positive strokes combined with the higher relative sensor gain (the ratio of sensor's peak current estimate to the NLDN-reported peak current) at larger distances.

Original languageEnglish (US)
Article number6605627
Pages (from-to)404-412
Number of pages9
JournalIEEE Transactions on Electromagnetic Compatibility
Issue number2
StatePublished - Apr 2014


  • Field-to-current conversion equation
  • National Lightning Detection Network (NLDN)
  • peak current
  • positive lightning
  • transmission line model

ASJC Scopus subject areas

  • Atomic and Molecular Physics, and Optics
  • Condensed Matter Physics
  • Electrical and Electronic Engineering

Cite this