lighting

[Munkeh]

what causes it?

[Azalian]

The short answer is;

Lightning in a thunderstorm occurs because the freezing process that takes place at the upper levels of a storm cloud separates +ve and-ve charges.

the action of rising and decending air in the updraughts and downdraughts of the storm widens the distance between the opposing charges and lightning is the discharge between the +ve and-ve sections of the cloud, i.e. top and bottom and betwen the cloud and the surface of the earth.

Air around a lightning strike can be heated to more than 20,ooo degrees C , thunder is caused by the superheated air collapsing in on itself when the lightning passes.

[Ice.Maiden]

Azalian's right - if it's lightning you mean.

[buildersmate]

The answer to the question asked is:-
Lighting includes both artificial light sources such as lamps and natural illumination of interiors from daylight. Lighting represents a major component of energy consumption, accounting for a significant part of all energy consumed worldwide. Artificial lighting is most commonly provided today by electric lights, but gas lighting, candles or oil lamps were used in the past, and still are used in certain situations. Proper lighting can enhance task performance or aesthetics, while there can be energy wastage and adverse health effects of lighting. Indoor lighting is a form of fixture or furnishing, and a key part of interior design.

[yon]

lack of darkness!

[enotrapfodne]

the weather