northern vs northernness

northern is not a noun while northernness is a noun.

Word	Noun	Adjective	Verb	Adverb
northern	No	Yes	No	No
northernness	Yes	No	No	No

northern (noun)	northernness (noun)
	the property of being to the north

northern (adjective)	northernness (adjective)
situated in regions of the north
in or characteristic of a region of the United States north of (approximately) the Mason-Dixon line
coming from the north; used especially of wind
oriented toward the north