Large storms can produce hundreds of elves over theĬourse of a few hours. Globally averaged elve occurrence rate of over 3 elves/min) Satellite study observed around 600 sprites and over 5000 elves, with a Specially-designed photometric imaging instruments have shown that elves areĮasily the most frequently occurring TLE on the planet (a recent 3-year Naked eye and difficult to catch on standard 30 fps video cameras, but use of The rapid timescales make elves too quick to see with the ElvesĮxpand radially outward along the lower edge of the ionosphere (80-90 km) withĪn apparent speed faster than light and can attain diameters up to 300 kmĪcross (covering an area similar to the size of West Virginia) on timescalesįaster than 1 ms. Elves are rapidly expanding rings of predominantly red lightĬentered well above a causative cloud-to-ground lightning return stroke.The now-accepted theory of sprite formation was Milliseconds to several tens of milliseconds, long enough to be barely Streamers and streamers can appear without halos. Highly structured streamers of a blue color, although halos can appear without Often, the highest parts of a sprite feature aĭiffuse, red glow (called a halo) while the lower parts of a sprite feature A single sprite can span altitudes from 40 km up to 80 km (theĬloud itself is no higher than 15 km) with a width of several tens of Lightning flashes that remove large amounts of charge from the upper portions Light occurring high above thunderstorms in response to cloud-to-ground Sprites are large, brief, and often highly-structured bursts of.Examples of various kinds of TLEs are shown in Figure Pinned down), and the entire category of flashes came to be known as transient To steer clear of names suggesting causative mechanisms which had not yet been “sprites” and “elves” to reflect their fleeting and hard-to-catch nature (and The different kinds of flashes were given fanciful names like Within a few years a menagerie of different kinds of flashes had beenĭiscovered. The subject of lightning-associated high-altitude (above cloud) flashes, and Of the photograph of the flash stoked a great amount of scientific interest in ![]() This changed inġ989 with the first scientific documentation of a brilliant optical flash wellĪbove a thunderstorm, following years of intermittentīut persistent verbal reports of such high-altitude flashes by pilots and Thunderstorm clouds and between the clouds and the ground. Offered by a thunderstorm was confined to the lightning activity in the Until recently, it was thought that the dazzling display of light
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