Grades K–2 · Earth & Space
How can dripping water make an icicle longer?
An icicle can begin where liquid water reaches a very cold edge. Some water freezes there instead of falling away. A small piece of hanging ice becomes a starting point.
In the diagramSome arriving water freezes onto the tipearlierlater
More water runs down its surface. If some of that water freezes near the tip, it adds ice lower down. Repeated arrivals can make the icicle longer, while freezing along the sides can make it thicker.
Not every drop stays. Some drops fall before freezing, and warmer conditions can melt the ice again. An icicle’s changing shape depends on both the supply of water and how much of it freezes.
About this explanation
Starting knowledge: Know that liquid water can freeze into solid ice in cold conditions.
Sources
- Maine Department of Agriculture, Conservation and Forestry — Nature Note 118: Winter Wonder — Icicles