Atmospheric electricity is the regular diurnal variation of the Earth's atmospheric electromagnetic network or, more broadly, any planet's electrical system in its layer of gases. The normal movement of electric charges among the Earth's surface, the various layers of the atmosphere, and especially the ionosphere, taken together, are known as the global atmospheric electrical circuit. A part of Earth Science, much of the reasoning required to explain these currents can be done within the field of electrostatics. Full understanding requires knowledge of several disciplines, not just electricity.

Eliminating, for the moment, consideration of the extremely dense charge populations that exist in the upper reaches of the atmosphere, a region called the ionosphere, filled with hot, dense, plasma gas whose ions give the ionosphere its name, we note that there is always some amount of unbound positive and negative, but net positive, electric charge in the atmosphere closest to the surface of the negatively charged Earth on a 'fine day'. When days are not so 'fine', the net unbound charge that exists in the clouds of thunderstorms can be exceedingly negative.

The 'fine day' net positive charge sets up an electric field between the negative Earth and the net positive charge in the air, and this electric field stores electrical energy. The positive charge acts by induction on the earth and electromagnetic devices.[2]

Experiments have shown that the intensity of this electric field is greater in the middle of the day than at morning or night and is also greater in winter than in summer. In 'fine weather', the potential, aka 'voltage', increases with altitude at about 30 volts per foot (100 V/m), when climbing against the gradient of the electric field.[3] This electric field gradient continues up into the atmosphere to a point where the voltage reaches its maximum, in the neighborhood of 300,000 volts. This occurs at approximately 30-50 km above the Earth's surface.[4] From that point in the atmosphere up to its outer limit, nearly 1,000 km, the electric field gradient produced in the lower atmosphere either ceases or has reversed.