US lab maps 76,000 lightning pulses to reveal storm power secrets

Researchers at Los Alamos National Laboratory have compiled the largest-ever dataset of high-frequency lightning radio signals, analyzing over 76,000 trans-ionospheric pulse pairs (TIPPs) to understand how lightning energy radiates depending on its altitude within clouds. TIPPs, the most powerful natural radio signals generated by lightning, were detected using a specialized radio frequency sensor and matched with satellite observations from a geostationary orbit. The study revealed that the relative strength of the two pulses in a TIPP—one direct and one Earth-reflected—is influenced by the lightning’s altitude and its angle relative to the satellite, solving a longstanding question about why the second pulse is sometimes stronger. This research provides new insights into compact intracloud discharges, a fast and short-lived form of lightning, and offers a method to more accurately measure cloud convection heights. Such measurements could improve storm monitoring by indicating rapid changes in storm dynamics. The extensive TIPP database is expected to enhance the accuracy of data from the Global Lightning