Time Correlations of Lightning Flash Sequences in Thunderstorms Revealed by Fractal Analysis

Xueqiang Gou, Mingli Chen, Guangshu Zhang

Research output: Journal article publicationJournal articleAcademic researchpeer-review

1 Citation (Scopus)

Abstract

By using the data of lightning detection and ranging system at the Kennedy Space Center, the temporal fractal and correlation of interevent time series of lightning flash sequences in thunderstorms have been investigated with Allan factor (AF), Fano factor (FF), and detrended fluctuation analysis (DFA) methods. AF, FF, and DFA methods are powerful tools to detect the time-scaling structures and correlations in point processes. Totally 40 thunderstorms with distinguishing features of a single-cell storm and apparent increase and decrease in the total flash rate were selected for the analysis. It is found that the time-scaling exponents for AF (α AF) and FF (α FF) analyses are 1.62 and 0.95 in average, respectively, indicating a strong time correlation of the lightning flash sequences. DFA analysis shows that there is a crossover phenomenon—a crossover timescale (τ c) ranging from 54 to 195 s with an average of 114 s. The occurrence of a lightning flash in a thunderstorm behaves randomly at timescales <τ c but shows strong time correlation at scales >τ c. Physically, these may imply that the establishment of an extensive strong electric field necessary for the occurrence of a lightning flash needs a timescale >τ c, which behaves strongly time correlated. But the initiation of a lightning flash within a well-established extensive strong electric field may involve the heterogeneities of the electric field at a timescale <τ c, which behave randomly.

Original languageEnglish
Pages (from-to)1351-1362
Number of pages12
JournalJournal of Geophysical Research: Atmospheres
Volume123
Issue number2
DOIs
Publication statusPublished - 27 Jan 2018

Keywords

  • AF and FF scaling methods
  • DFA analysis
  • lightning flash
  • VHF radiation

ASJC Scopus subject areas

  • Geophysics
  • Oceanography
  • Forestry
  • Aquatic Science
  • Ecology
  • Condensed Matter Physics
  • Water Science and Technology
  • Soil Science
  • Geochemistry and Petrology
  • Earth-Surface Processes
  • Physical and Theoretical Chemistry
  • Polymers and Plastics
  • Atmospheric Science
  • Earth and Planetary Sciences (miscellaneous)
  • Space and Planetary Science
  • Materials Chemistry
  • Palaeontology

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