GMAT Sentence Correction (SC) | Re: Floating in the waters of the equatorial Pacific, an array

The first thing is to note that a restrictive pronoun such as 'that' first refers to the noun it touches. If there is no such noun in front, then we have to hunt for some other distant but eligible noun. Since there is a noun, namely, atmosphere in front of that, the relative pronoun does refer to the atmosphere wrongly. Therefore, even if you were to change affects to affect, arguing that after all that refers to the plural data the choice will still be wrong as per GMT tenets, failing to