Magnetic field intensity
From Glossary of Meteorology
magnetic field intensity
The magnitude of the magnetic field at any point.
Strictly speaking, the magnetic field is the set of all values of the magnetic field intensity, but magnetic field and magnetic field intensity (as well as magnetic field strength and magnetic vector) are used more or less interchangeably. The trend is to use magnetic field both for the field taken as a whole and for its value at any point, context being sufficient to determine precise meaning.