The Earth generates a magnetic field from electric currents flowing in it s core.
All EMFs consist of an electrical field and a magnetic field.
Electrical fields exist only when there is a flow of electricity such as when you operate the electrical device. The electrical field is easily shielded or weakened by trees, walls, or human skin. The magnetic field portion of EMF cannot be as easily weakened as the electrical field can. The magnitude of both the electrical field and magnetic field varies with the amount of voltage, current, and the distance you are from the conductor. The strength of an EMF rapidly decreases with distance from its source.