Downward Lightning Hitting Tokyo Skytree Observed by High-Speed Camera

Abstract

Lightning hits to Tokyo Skytree have been under observation by a high-speed camera since August 2012. First data were obtained when negative downward lightning flashes hit the tower on July 08, 2013. This letter reports on observation of a negative single-stroke flash with a positive upward leader initiated from Tokyo Skytree extended about 400m before connection with a downward leader. Simultaneously observed electric field observed by a fast antenna showed much weaker stepped-leader pulses compared to ordinary negative downward flashes hitting ground.