Rotten ice
Rotten ice is a loose term for ice that is melting, disintegrating, or otherwise formed, having water, air, or contaminants between ice grains, causing the ice to be honeycombed. It forms on open water, when snowpack and ice are mixed together and other conditions. It may be transparent, causing it to look like new black ice. Though it may appear strong, rotten ice is weak — even several feet thick may not hold a person's weight (although it may hold a dog sled's weight). On land, it is difficult or impossible to climb. It melts more quickly than solid ice. Candle ice is a form of rotten ice. One way to tell that ice is rotting would be the grey, splotchy color. Also, the thickness of ice cannot determine how safe it is, because water from underneath the ice can erode the ice and cause it to be thinner without a sign on the surface. Even thick ice may be weak, especially if it has frozen and thawed repeatedly or if it contains layers of snow. Minerals in the water make vertical veins in the ice. These veins melt much faster than the rest of the ice causing vertical channels and the ice to weaken along those channels. Many people tend to question if snow actually warms up ice, making it more likely to crack and break, or if snow actually causes ice to freeze faster. Snow will actually act like an insulating blanket. The ice under the snow will be thinner and weaker. A new snowfall can also warm-up and melt existing ice. Rotten ice is becoming more commonly found in the Beaufort Sea, near Alaska, due to different climate changes. This is concerning, because it is a sign that the amount of multiyear ice is declining, and it is being replaced with heavily decayed ice.
References
- Cooper, Donald C. (2005). Fundamentals of Search and Rescue. Jones & Bartlett Publishers. p. 112. ISBN 9780763748074.
- Ice and Refrigeration Illustrated. Nickerson & Collins Co. 1898. p. 92.
- "rotten ice". Glossary of Meteorology. American Meteorological Society.
- "Spring Ice is Rotten Ice" (PDF). Lifesaving Society Water Smart Facts. Lifesaving Society Alberta and Northwest Territories. February 2011.
- "Is ice 'rotten' in the Beaufort Sea". Science Daily. 21 January 2010.