Artist providing representation of sea mist (7)
I believe the answer is:
matisse
'artist' is the definition.
(Henri Matisse, 1869-1954, French artist)
'representation of sea mist' is the wordplay.
'representation of' is an anagram indicator (I've seen this in other clues).
'sea'+'mist'='seamist'
'seamist' anagrammed gives 'MATISSE'.
'providing' is the link.
(Other definitions for matisse that I've seen before include "Henri ---, Fauvist painter" , "Leading fauvist painter, d. 1954" , "20th century French painter" , "French painter, d. 1954" , "French impressionist" .)