Douglas sea scale vs international sea and swell scale

Douglas sea scale and international sea and swell scale both are nouns.

Word	Noun	Adjective	Verb	Adverb
Douglas sea scale	Yes	No	No	No
international sea and swell scale	Yes	No	No	No

As nouns, Douglas sea scale and international sea and swell scale are synonyms defined as:

Douglas sea scale and international sea and swell scale: scale used for measuring the height of waves

Other synonyms of Douglas sea scale include Douglas scale.

Douglas sea scale (noun)	international sea and swell scale (noun)
scale used for measuring the height of waves	scale used for measuring the height of waves