Because the Earth is a small charged body moving in a large cell of plasma, explanations of all physical phenomena in, on, and near the Earth must take the electrical behavior of plasma into account. The waterspout shows us once again that plasma behavior can take many different forms.
There are two types of waterspout; one type is simply a tornado over water. The other (true waterspout) is less powerful than a tornado. It forms in a different way and often in a different season. It dissipates quickly if it happens to move over land.