hypsometry vs hypsography

hypsometry and hypsography both are nouns.

Word	Noun	Adjective	Verb	Adverb
hypsometry	Yes	No	No	No
hypsography	Yes	No	No	No

As nouns, hypsometry and hypsography are synonyms defined as:

hypsometry and hypsography: measurement of the elevation of land above sea level

hypsometry (noun)	hypsography (noun)
measurement of the elevation of land above sea level	measurement of the elevation of land above sea level
	the scientific study of the earth's configuration above sea level (emphasizing the measurement of land altitudes relative to sea level)