Sublimation

Changing Snow or Ice to
Water Vapor

When describing the water cycle, sublimation is most often used to describe the process of snow and ice changing into water vapor without first melting into water.

Sublimation is a common way for snow to disappear in colder climates. When we get snow in Blanco, it mostly infiltratesthe soil to feed the aquifer, or occurs as run-off to feed the creeks).

It is not easy to actually see sublimation happen, at least not with ice.

One way to see the results of sublimation is to hang a wet shirt outside on a below-freezing day. Eventually the ice in the shirt will disappear.

Actually, the best way to visualize sublimation is to not use water at all, but to use carbon dioxide instead. "Dry ice" is solid, frozen carbon dioxide, which sublimates, or turns to gas, at the temperature -78.5 °C (-109.3°F).

The fog you see on stage at rock concerts is a mixture of cold carbon dioxide gas and cold, humid air, created as the dry ice sublimates.

Sublimation occurs more readily when certain weather conditions are present, such as low relative humidity and dry winds. It also occurs more at higher altitudes, where the air pressure is less than at lower altitudes.

Energy, such as strong sunlight, is also needed.

If I was to pick one place on Earth where sublimation happens a lot, I might choose the south side of Mt. Everest.

Low temperatures, strong winds, intense sunlight, very low air pressure - just what is needed for sublimation to occur.

Back to Water Cycle

Back to Blanco Water Issues

	Enter your searchtermsSubmit search form
	Web www.Blanco-Texas.com