She does say that she lives in San Diego now, even if she did live in Istanbul in the past.

And yes, I'd think it polite to apologize for blatant errors in the book, like putting Istanbul in a desert. Some of it is probably legitimate ignorant American teenager POV stuff (although I'd prefer more of an effort to try to correct the POV character's misapprehensions than it sounds like the author did), but some of it isn't, and they're such basic errors that I know I wouldn't be convinced that any research was done at all.