Lightning

Natural static dischargeMain article: Lightning
Lightning is a dramatic natural example of static discharge. While the details are unclear and remain the subject of debate, the initial charge separation is thought to be associated with contact between ice particles within storm clouds. Whatever the cause may be, the resulting lightning bolt is simply a scaled up version of the sparks seen in more domestic occurrences of static discharge. The flash occurs because the air in the discharge channel is heated to such a high temperature that it emits light by incandescence. The clap of thunder is the result of the shockwave created as the superheated air rapidly expands.