FORTE Compact Intra-cloud Discharge Detection Parameterized by Peak Current

M J Heavner, D. M. Suszcynsky, A. R. Jacobson, B. D. Heavner, and D A Smith

LAUR-02-5759

Conclusions/Summary

This study was motivated by the VLF NBE amplitude thresholding in the GPS/LASA lightning observations. We have examined FORTE/VHF lightning observations and do not find a similar threshold effect. Any minor threshold effect is probably masked by other physical effects--possibly non-isotropic CID/NBE radiation, or a lack of any strong VLF/VHF power relationship. The large number of VLF NBE events which FORTE/VHF `missed' have many large amptidue VLF NBE events, indicating that additional physical insight into the CID process is needed to understand the discrepency between VLF and VHF observations.

Future Directions

The data set presented here is biased towards Florida thunderstorms. Efforts towards studying more storm types are underway, including the recent participation in a Brazilian lightning campaign. This study began with LASA/VLF NBE observations and looked for matching and missed FORTE/VHF events. A complimentary study of FORTE/VHF TIPPs while in view of LASA is currently underway.

Bibliography

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[2] V.P. Idone, et al., Performance evaluation of the U.S. National Lightning Detection Network in eastern New York 1. Detection efficiency. JGR, 103(D8):9045, 1998.

[3] A. R. Jacobson, et al., FORTE observations of lightning radio-frequency signatures: Capabilities and basic results, Radio Sci, 34(2):337, 1999.

[4] D. A. Smith, et al., The Los Alamos Sferic Array: Ground truth for the FORTE satellite, J. Geohpys. Res., 2000.H4

[5] D. A. Smith, et al. The Los Alamos Sferic Array: A research tool for lightning investigations. JGR, 107(D13):10.1029/2001JD000502, 2002.

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Acknowledgements

This study was possible due to the hard work of the FORTE team. This research was supported by the Department of Energy. Ryan Woodard and Laura Peticolas contributed to software development.

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