Not that I'm picking on this poster, but it was a good example of what is wrong with most amateur ghost hunting these days. This image, found on flickr, was tagged as a spirit mist. If you click on the linked image, you will see that someone has placed a note into the picture as well, stating they see a man dressed in black with a ruffled collar in the image.
I see snow on the ground and a mist clinging near to the lens. It doesn't take much to connect the two.