Arctic Revue Day 4 "Aufeis"

One of the potential hazards of river travel in the Arctic is aufeis -- ice leftover from previous winters that never completely melts during the summer.  Aufeis is basically a riparian glacier, which grows each winter and partially melts each summer.  A single sheet of aufeis can consist of 10 years of accumulated ice.

In the first seconds of the video, look for the river flowing underneath the ice.  When you're travelling on the river and you come to some aufeis, you hope for a place where enough ice has melted that will allow you to pass through.  Otherwise, you need to cross over the ice, using extreme caution.  Yes, that means haulling the kayak packed with gear and sliding it over the ice like a sled.  Not my idea of a good time! 

Aufeis on the Kongakut River

We encountered aufeis on several occasions, and fortunately, each time there was a way around it or through it.  The height of the aufeis in the picture is about 3-4 feet high, and it covered about half an acre.   The presence of aufeis ensures that the water is VERY cold.  On the first day we just wore synthetic pants, but the chill of the water cut right to the bone.  The next day we broke out the neoprene wetsuits (which we just happened to bring "in case" and which provided ample relief from the cold water).  These patches of ice in the middle of June were an effective reminder that this was an Arctic expedition.