This category of photos has a consistent colour palette. There are some icy tones including blues and greys. These tones are primarily there already but slightly developed through editing afterwards.
The simplest way I found to do this was change the photo to monochrome. On some of the colour photos I added a grey/blue tint or increased the natural tones using a action called auto colour on PhotoShop.
Many of these photos are macro, using a very short depth of field. For example I used a short f-stop while photographing some ice on a fence. This created an intense effect and much of the surrounding area was blurred while the focus of the ice in the middle was very clear.