What is magnetic field
We always believe the earth is a big magnet, Magnetic field maps on the kilometre scale can help locate geological formations that indicate the presence of oil or other minerals. And on the largest scale, the Earth’s field reveals details about the geodynamo that generates it.
But there is an intermediate scale over lengths of tens to hundreds of kilometres that is relatively poorly studied. In theory, this should reveal important details about the behaviour of the outer mantle, the solar-quiet dynamo in the ionosphere and ionic currents in salt water that could be used to measure ocean circulation, a major factor in models of climate change.
The data this produces should provide a new way of studying the structure of the Earth at a scale that has been largely ignored until now. A good time to be a geophysicist.
Magnetic field changing
The earth protects us from harsh phenomenon of space by magnetics which we can’t even see by our eyes, magnetic field that our planet generate only tells you compass which way you are leading to
A new study suggests that our planet’s poles could indeed shift, and shift much more rapidly than previously thought.As Proceedings of the National Academy of Sciences, researchers say that they have found evidence that Earth’s poles have shifted quickly in the past, and if that were to happen again it could cause global calamity.
How do we understand this magnetic pole shift of big magnet, there are many domains in all things, like atom, molecule inside the magnet, the orientation is different until we magnetize them with strong field, and give north and south pole to magnet, so does earth, magnetic declination is always there and changed according to our oversavation in past 10 years manufacturing experience.