Heliyon (Mar 2023)
Catalog of 525 sprites observed over Japan from September 2016 to March 2021
Abstract
We present a catalog of 525 sprites detected over the Sea of Japan and a northeast part of the Pacific Ocean from Sagamihara between September 2016 and March 2021. We analyze the morphology of 525, estimate the location of 441, and calculate the accurate top height of 15 sprites. More than half of our samples occurred in winter, while only 11% were in summer. In terms of morphology, 52% to 60% column type sprites took place in spring, autumn, and winter, while only 15.5% in summer. Therefore, summer thunderstorms are more likely to produce sprites with complex structures like carrots. Furthermore, sprites in summer are almost all located on the main island of Japan, and their spatial distributions are significantly different from the other seasons. Finally, from the perspective of the time distribution, the number of sprites is the largest at 1:00 JST. In addition, the morphology of sprites tends to be simple (e.g., a column type) at midnight JST.