Ansel Adams
Good catch! I would suggest that it's certainly meant to emulate the grandeur of Adams' work. An easy mistake to make imo. How did you happen to catch it? Is the style that discernibly different to your eye, are you an Ansel Adams or Peter Essick afficanado or did you just happen to read the credit at the bottom of the image?
I'd agree with your suggestion, the photo definitely 'feels' like an Adams in that it's a grandeur landscape with dramatic lighting and a good spectrum of light and shadow. When I saw the thumbnail two things occurred to me: 1. The exposure isn't as technically proficient as Adams' tend to be, there's less contrast between the brightest and darkest tones and there's less 'punch' overall 2. I haven't seen this picture before I'm not hugely studied in Adams' work, it's not like I've seen or can recognize every print he's ever made, but it felt 'off' enough for me to be curious and to view the full resolution image. Without the caption I would have fully believed it to be a photo by Ansel Adams, though. I'd never heard of Peter Essick before.