Red Sprites and Blue Jets: Transient Electrical Effects of Thunderstorms on the Middle and Upper Atmospheres

Four new and diverse classes of energetic electrical effects of thunderstorms have been documented over the past 5 years. Two of these classes, called red sprites and blue jets, are large-scale optical emissions excited by lightning. Together they span the entire distance between tops of some thunderstorms and the ionosphere. Gamma-ray (1 MeV) bursts and extremely intense VHF radio bursts some 10(exp 4) times larger than normally produced by lightning have been observed from low Earth orbit and are also believed to originate in thunderstorms. Taken together, these newly discovered classes of natural electrical phenomena provide evidence that thunderstorms are both more energetic and capable of electrically interacting with the upper atmosphere and ionosphere to a far greater degree than has been appreciated in the past. Here, characteristics of red sprites and blue jets are summarized.