Thin ice hidden under snow at upper end of Yukon Slough No flash player has been set up. Please select a player to play Flash videos. Video not playing? Update your browser or download the video clip Knut Kielland shows how close thin, unsafe ice can be from thick, solid, safe ice, and how easily this can be hidden under the snow. Process Observed: Open Water (Hidden)Thin IceThick Ice Date Process Observed: Wednesday, March 23, 2011 Galleries: Upper end of Yukon Slough Gallery