Satellite-based Lightning Risk Quantification

Over the years, the lightning fatalities in the United States have greatly decreased with the increase of lightning safety awareness and education. The current lightning safety saying of “when thunder roars, go indoors” is more reactive than proactive, as action is not taken until thunder is audibly heard, meaning lightning is already present. To help people further monitor their safety, a lightning risk tool has been developed between Texas Tech University, the University of Alabama in Huntsville, and NASA SPoRT. The tool can provide tailored trends in lightning risk magnitude over time by incorporating the user’s specific location, an event venue, or other location of interest.

A challenge with the lightning risk methodology is that Lightning Mapping Array (LMA) data is used, which means risk can only be calculated at locations that fall within an LMA domain (which are limited in spatial coverage). However in the last 6 years, Geostationary Lightning Mapper (GLM) data from NOAA’s GOES-R Series have become available, which allows for spatial mapping of lightning data across much of the Western Hemisphere. Using this space-based lightning mapper data allows for risk to be calculated within a much larger domain. One of the challenges of this transition is that the GLM resolution is larger than the LMA, which may lead to GLM-based risk producing larger risk magnitudes. To gain a better understanding of GLM-based risk, the present study compared risk calculations for identical situations using both LMA and GLM data as input. A database of twelve cases was created, using known lightning fatality, lightning injury, or decision support events where lightning threatened people or large outdoor venues. Results highlight initial conclusions on the magnitude of impact of using the coarser resolution GLM data in place of LMA data. Ultimately, a better understanding of how to use a space-based lightning risk tool can expand its locational application, and even consider areas in Europe and Africa through use of the Meteosat Third Generation Lightning Imager (MTG-LI) in the future.