Sprites and possible mesospheric effects

Images of sprites have been recorded at 1 ms resolution revealing several n ew sprite properties. Sprites appear to occur in a highly structured mesosp here, and we suggest that the cause of some of this structure is the sprite activity itself. Evidence is seen in events where a subsequent nearby spri te appears to re-activate the volume of a previous sprite, in sprites where tendrils and branches develop away from the normally observed vertical dir ection, and in beads that lasts much longer that the parent sprite. Sprites can be large with horizontal widths of more than 40 km and can extend from the clouds up to the lower ionosphere thus affecting a large volume of the atmosphere, The total horizontal area of sprites during one storm over Neb raska was a significant fraction of the area covered by the associated thun derstorm raising the possibility of larger scale measurable mesospheric eff ects.