Background: Students at Old Town High School in Maine have been measuring snowpack (snow on the ground) during the course of the winter in 2013-2014. They have been making lots of types of measurements of the snow, and one important one is snow water equivalent. Snow water equivalent tells you how much water is in the snow – so it’s like a depth of water that, if all the snow melted at once, would blanket the ground.

The students measure snow water equivalent at two types of sites: some that are open (without many trees overhead) and some that in the forest, with lots of tree cover. They are wondering if the amount of snow water equivalent is different, depending whether you are in the forest or in the open. Anyone who has stood under a tree to avoid being rained or snowed on knows that the tree canopy can act like a bit of an umbrella, not letting all of the rain or snow through. When the snow is sitting on the ground and the weather starts to warm up, the tree cover starts to act like shade and could keep the snow colder – and therefore on the ground longer.

The graph shows snow water equivalent in feet for the open and the forested sites in Old Town during winter 2013-2014. As it begins to snow in December, the snow water equivalent starts to build up. In March, snow starts to melt a bit.

Data Source: E. Lindsey, Old Town High School.