I also think it's important to recognise that Q22 isn't intended to say "why we must on no acccount put your favorite scientific paper in this article".  It's only there to explain the kind of thing you would have to demonstrate in order to get a reference to the paper into the article.  So if there's some aspect of climate change research that is poorly represented by existing sources in this article, and you know a paper that is generally agreed to be representative of that aspect, then referring to that individual paper may well be the best thing to do, though of course it's still true that literature review papers, reviews by recognised scientific institutions, text books and the like are generally more suitable at this summary level. TS