Answer:
Which is very severe in the Arctic
Step-by-step explanation:
Adjective clauses are clauses modifying, describing or giving more information about nouns. We can identify them because they are usually placed right next to the noun they describe, and beginning with a relative pronoun (who, whom, whose, that or which) or a relative adverb (when, where or why). In the sentence, “Which is very severe in the Arctic” is the adjective clause because it describes and gives us information about the noun “The weather.”