Webster’s Dictionary has both declination and variation for the angle between the magnetic and geographical pole, but when I was in the Air Force we always called it variation.
I am impressed by how rapidly the movement of the North magnetic pole is accelerating.
I’ve been looking at this movement for a while: the very rapid recent movement is amazing, when compared to several centuries of fairly stable (less than 100 km total) position since the mid 1600’s.
Now, it rocketing off towards Siberia.
More relevant towards global warming - actually, since global warming appears caused BY the greater and lesser shielding from cosmic rays by the (lesser or greater) magnetic field of the sun interacting with the earth, the century-long DECLINE in the earth’s magnetic field by over 12%, combined with the movement of the earth’s northern magnetic pole, bodes interesting effects.
Less shielding, more cosmic radiation interaction with the atmosphere, more cloud nuclei form, more clouds, more reflectivity, more reflectivity means cooler temperatures.
Now, assuming a constant earth’s magnetic field, more solar activity means more magnetic field and a greater solar wind, and thus more protection and fewer cosmic ray interactions. Fewer interactions mean hotter average temperatures - which is what we are seeing.
But a decline in the earth’s magnetic field might offset part of this increase in global temperatures caused by less cloud cover:
Declination has an entirely different meaning in regards to navigation. Declination is an angular measurement of a celestial body.