Bright sprites (left of frame) above a thunderstorm near Sniezka, Poland on 20 July 2007 (credit: SPARTAN Sprite-Watch team)
In search of sprites
With their lightning, thunder and torrential rain, thunderstorms are pretty impressive from below. But it’s the spectacular light shows above the clouds that scientists are watching.
If you look at a distant thunderstorm at night, you may be lucky enough to see a flash of red light above the clouds known as a sprite. These enormous flares appear above the cloud tops and reach 80 kilometres high and several tens of kilometres wide, yet the whole scene lasts just a few milliseconds. They belong to a family of elusive electrical discharges that includes elves, sprite haloes, blue jets, blue starters and gigantic jets.
First scientifically documented in 1989, the worldwide hunt for sprites continues through small-scale observational campaigns. The distribution of sprites across the globe, and how that varies with time, is still poorly understood. This information is essential for understanding the electric currents flowing around the Earth. Since 2003, European scientists collaborating in the EuroSprite campaign have been looking for sprites using low-light TV cameras installed in the Pyrenees, France and, in the summer of 2007, in Corsica.
Postgraduate students from the University of Leicester have joined EuroSprite, and have set up a camera in Poland, where sprites had not been seen up until now. During their two-week campaign at a mountaintop observatory on the Czech – Polish border the team were excited to see four sprite events produced by thunderstorms on 20th July over Germany, Poland and the Czech Republic.
You can read a blog of the latest sightings by scientists across Europe by following the link below.
