A waterfall is one of nature's many spectacles. Most of us have stood transfixed by falling water at one time or another -- we pause to listen to a trickling falls as we hike through the woods or marvel over the power of Niagara. But during the winter some waterfalls completely transform. Where they once rushed roaring water, they now stand frozen, white and silent. This oxymoron of a motionless falls is an ice climber's dream.
Generally, there are two kinds of ice climbing -- alpine and waterfall. As you might surmise from its name, you'll find alpine ice in a mountain environment. It's part of the terrain, may be steep or flat, is primarily derived from snow and is sometimes mixed with rock. Waterfall ice, on the other hand, is vertical, frozen water. There are two types of frozen waterfalls: one type forms from a legitimate waterfall and one type forms from temporary runoff after a particularly heavy rain.
It's probably hard to imagine that the rushing water of a falls could freeze, but it can. Here's how it happens. In freezing temperatures, water molecules begin to slow down and eventually stick together, which is how water changes from a liquid to a solid. The snowball effect of those gumming water molecules results in a waterfall that's frozen in midair. Climbers are attracted to frozen waterfalls because the surface is always changing. Midday sun, changing temperatures, precipitation and runoff will send new trickles of water down to refreeze in different formations. So, if you "scar" the ice today with your tools, in a week or two the scar will be gone, replaced with a newly frozen bump or ridge.
Frozen waterfalls form in several ways, and their formation can provide clues about how safe they are to climb. If a frozen waterfall is attached solidly to its ice base and appears to be bonded to a supporting wall of rocks, it's safer and more stable, as long as the ice is cold and strong. However, if the ice wall formed from water that flowed over a ledge, it may be a freestanding column or hang like a giant icicle. Hanging ice waterfalls are the most dangerous from a structural standpoint because they're not solid -- they're a fusion of many giant icicles. Without a base support, these frozen falls may snap and collapse in the blink of an eye.
Waterfall Ice Climbing
Seasoned ice climbers say the best ice climbing in North America is found in the Canadian Rockies, where there are frozen waterfalls for all skill levels and hundreds of climbs available from late November through March. In the United States, you can find frozen falls in Colorado, Wyoming and even California. Norway has some of the best frozen waterfall climbing in the world, and it even hosts an ice climbing festival each February.
Climbing water ice is a bit different from climbing alpine ice. One of the cool things about water ice climbing is that you don't have travel up to the highest mountain peaks to start climbing. Obviously, frozen waterfalls and runoff are found downstream. A waterfall climb is by nature always vertical, which requires more advanced climbing skills and specialized tools. Using crampons --spikes attached to the bottom and front of your boot -- and ice axes, you can Spiderman your way up vertical ice. To learn more about specific ice climbing techniques and tools, read "How Ice Climbing Works".
Water ice is also unique because it tends to be colder and more brittle than alpine ice. Brittle and dry ice is likely to break and shatter, what climbers call dinner plating. However, you can encounter dozens of different types of ice during a frozen climb. Ice climber Jeff Lowe has listed the common types of ice a climber might encounter. This list is by no means complete.
- Verglas: ice less than 0.5 inches (1.27 centimeters) thick
- Thin ice: ice 0.5 to 6 inches (1.27 to 15.24 centimeters) thick
- Laminated flow: successive freezing of thin layers of ice
- Chandeliered: clusters of hanging icicles
- Cauliflowered: ice formed in strange and unstable formations, usually the result of water spray
- Solid pillar: well frozen and cohesive ice
- Rotten pillar: melting, chandeliered or cauliflowered ice
- Small pillar: ice less than a foot (30 centimeters) in diameter
- Aerated: ice with lots of bubbles or melted pieces
- Plastic: ice that is warm but not rotten, and doesn't shatter
- Mineralized: brittle ice and colored brown, orange or yellow
- Blue/green: well frozen, sometimes brittle ice
- Old dry: very durable ice
How can you predict what the ice will feel like during your climb? It's hard to say. Ice can go from hard to brittle to slushy all in one climb. If temperatures are well below freezing, you may encounter brittle ice, which tends to break off in plates when you swing your tool into it. When temperatures are near or above freezing, the ice may feel plastic. Your pick will sink in quickly and stay there, making climbing easier and faster. If temperatures are warming to above freezing, ice may become slushy and soft -- not good climbing conditions.
Because there are so many different kinds of ice to deal with, ice climbing a waterfall is typically an endeavor for an advanced ice climber. The best climbers are those who can easily recognize stable and unstable ice and improvise accordingly.
To find out more about ice climbing and other outdoor sports, visit the links on the next page.
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More Great Links
- Becher, Bill. "Where Waterfalls Freeze, There's a Path to the Top." New York Times. March 6, 2008. (Oct. 8, 2008)http://www.nytimes.com/2008/03/06/sports/othersports/06ice.html
- Bianchi, Alberto. "Frozen Waterfalls: How They Develop, How They Collapse." December 2004. (Oct. 8, 2008)http://www.hans-bergmann.at/files/Eisfallstudie.pdf
- Heidorn, Keith. "Frozen Niagara Falls." The Weather Notebook. 2008. (Oct. 8, 2008)http://www.weathernotebook.org/transcripts/2001/03/29.html
- "Ice Climb Science: How the ice forms, de-forms and fails." Iceclimb.com.1999. (Oct. 8, 2008) http://www.iceclimb.com/science.html
- "Ice Climbing (Waterfall) - Sierra and Rockies." American Alpine Institute. 2007. (Oct. 8, 2008)http://www.mtnguide.com/ProgramDetail/ice_climbing/
- Lowe, Jeff. "Ice World." The Mountaineers Books. 1996. (Oct. 8, 2008)
- "Postcards from Home: How do those falls freeze?" Minneapolis Observer Quarterly. Dec. 6, 2005. (Oct. 8, 2008)http://www.mplsobserver.com/node/486
- Reucroft, Stephen and Swain, John. "How can waterfalls freeze when the water is in motion?" Boston.com. March 26, 2007. (Oct. 8, 2008)http://www.boston.com/news/globe/health_science/articles/2007/03/26/how_can_waterfalls_freeze_when_the_water_is_in_motion/