serves to ionize the air is this an accurate statement my understanding was that once the stepped leader connects with a positive streamer or another object the channel is formed and the air is ionized why then does the air need to be re ionized by the dart leader if it's already ionized by the initial stepped leader and the lightning flash i think the article needs toe be fleshed out a bit more and citations added i'm sure plenty can be found at meteorology sites maybe noaa if thay have a glossary or ams etc