Elements of geomagnetism
In order to specify the earth’s magnetic field completely at a place i.e., to know the magnitude and direction of the geomagnetic field intensity, the parameters which are needed to know are called magnetic elements of the earth.
The Earth’s magnetic field at any point on the Earth can be completely defined in terms of certain quantities called magnetic elements of the Earth. There are three elements of earth’s magnetism:
(1) Declination is the angle on the horizontal plane between magnetic north and true north.
(2) An angle of Dip or inclination is the angle made with the horizontal by the Earth’s magnetic field lines.
(3) The horizontal intensity of the earth’s magnetic field.
The accurate reason of magnetic field of Earth is not yet identified but some significant postulates are:
- The magnetic field of Earth might be due to molten charged metallic fluid in the core. This rotating fluid results in currents thus magnetizing the Earth.
- Since every material is made up of charged particles, these substances’ rotating about an axis is equal to a circulating current and therefore is responsible for the Earth’s magnetization.