Looking for a short story I read years ago where a man sets out into an icy wasteland, possibly the south pole. He gets turned around, and finds footprints and sees people who he assumes may be there to bring him back to safety. He also fears he is being chased by something hostile. He encounters a few camps, some of which were hastily set up or quickly abandoned. In one of the camps he finds a journal, which is what clues him into the truth - that he's been going in circles in both space and time, and the camps and footprints were his. I can't remember, but I think he finds a dead body that's frozen unrecognizable, which turns out to be him. I do remember there's a bit where he sees someone standing at the top of a pass of some sort, and tries to get their attention, and later a bit where he stands at the top of the same. I think the story ends with him dying, and possibly his colleagues bringing his body back, finding that he didn't get very far at all toward his destination. May or may not have been written in the form of journal entries. Also seems like there was something about a looming presence in the direction of his destination, but I might just be thinking of the bird from "I Have No Mouth and I Must Scream" on that one.