This looks slightly overprocessed to me - there are some halos visible near the mountains on the right and the tree looks a bit 'odd' too.
Nevertheless, nice shot :)
This is a lovely scene with the solitary tree and no one to be seen in this image. The mountains as they meet the sea are particularly appealing.
Problems: the fg looks like some kind of parking lot and perhaps could be cropped out.
The sky has a lot of noise. Perhaps a de-noise program could be used.
This is cool. The noise makes the picture seem like it's not a photograph, which is interesting.
I like the lone tree, composed to the left side of the frame, the colors are a little dreary, which gives an even bigger impression of loneliness, in my opinion.