Preliminary Reports of Summer Sprite Observation Campaign at Summit of Mt. Fuji, Japan

An isolated-mountain observation was conducted at the summit of Mt. Fuji (3776 m), Japan, to detect transient luminous events (TLEs) off the coast of the Boso Peninsula, Chiba, and the east coast of Japan. Many TLEs caused by energetic positive cloud-to-ground (+CG) lightning occurred in this region during the summer of 2013. Since the summer clouds covering the ground and ocean are usually located below the summit, a 360° view from the isolated mountain along with low atmospheric pressure and unpolluted air over the summit is expected to facilitate the observation of TLEs and their vivid color images, respectively. We detected several distant TLEs with light-sensitive black-and-while CCD cameras and a color single-lens reflex camera. We analyzed the relationship between a sprite and its parent +CG lightning and storm during this study. Six sprite events were associated with +CG lightning, and their estimated amplitude was 156 ± 76 kA (89-312 kA). Sprites appeared 41.4 ± 29.8 ms after +CG lightning. The +CG lightning with sprites were located in the stratiform precipitation region.