How Much Liquid Water in a Foot of Snow?

This past weekend’s blizzard covered New England with several inches of snow and will be remembered as one of the largest (and longest!) storms to coat Burlington in memorable history.

The snow could not have hit at a better time for our elementary schools though, as many of Burlington’s fourth graders are either wrapping up or just starting their science units on weather and climate!

A question often asked by students (and adults) is how much liquid water is there in a foot of snow? When learning about matter, students learn how matter contracts as it gets colder taking up less space, and expands as it gets warmer (taking up more space!)

But water is not like most matter. Thanks to water molecules electronegativity its molecules organize themselves into a special six-sided arrangement that produces a perceived hollow crystal interior. When ice and other forms of solid water are heated up, the arrangement breaks down, the hollow space collapses and the water “melts” into its liquid form. As you can see in the diagram below, liquid water ends up taking up less space than solid water and is therefore more dense than ice!

This phenomena has a profound effect on our Earth! Since ice floats the tops of Earth’s bodies of water freeze over while marine creatures live below. If ice was more dense (like most matter) ice would sink to the bottom, crushing marine creatures below and leaving our seas and rivers relatively lifeless!

Consider trying this experiment with your students or children and see if you get the same results! We are familiar with many different “kinds” of snow (light and fluffy, wet and sticky to name a few!) Do all of these snow types melt into the same amount of water? Does location matter? Allow your students and kids to explore the possibilities and maybe devise their own experiments!