High-speed footage of cloud-to-ground (cg) lightning, as seen from an aeroplane. The lightning strike begins with the formation of short leaders, glowing channels of ionised air through which current flows. These head downwards from the base of the cloud until they meet the ground, at which point an enormous return stroke travels rapidly up the channel from the ground to the cloud. Once the channel is established, charge travels through it several times, which is responsible for the flickering appearance of lightning when seen in real time. Filmed in the USA in the late afternoon in summer. |