Overview
Water isn’t the only thing that travels around in our atmosphere. Dust, pollen, and other small particles become incorporated into our atmosphere and become the nucleus for water vapor to settle on, creating rain and snow.
Introduction
This activity helps students understand the components of clouds, snow, and rain.
Grade Level
K-5, 6-8
Learning Objectives
Students will be able to identify what comprises a snowflake or raindrop: dust, pollen, other small particles, and water vapor.
Lesson Format
This activity can be done indoors or outdoors
Time Required
30 min
Credits & Contact Info
Trisha Smrecak and Caroline Boyajian
Paleontological Research Institution, 1259 Trumansburg Rd., Ithaca NY 14850
climate@priweb.org
Instructions & Materials
Materials
- a group of at least 10 people
- something to use as an identifier for individuals (stickers, hats, etc.)
Instructions
- Break participants into two equal groups: water molecules and dust particles. You may wish to give each participant a visual representation of their group (like blue and brown stickers, hats, or by blindfolding the dust particles).
- Tell participants to ‘drift around’ the atmosphere slowly and quietly.
- When they bump into someone from the opposite group (water vapor into dust particles), they join hands. Multiple waters may attach to a single dust particle, but not the reverse.
- As participants pair up, they continue to drift around the room until most or all water molecules have attached to a dust particle. Yell freeze to pause gameplay and prompt discussion.
- Repeat the game with fewer water molecules and more dust particles, or the reverse. Have students predict what will change and compare it to the real-world scenario.
Discussion
Snowflakes are created by water vapor bumping into tiny dust particles, and through the process of sublimation, the water vapor turns into an ice crystal. This ice crystal grows by bumping into other water vapor molecules and dust particles. When the molecule becomes heavy enough, it falls to the ground as precipitation. If there are lots of water molecules and only a few dust particles, either less precipitation will fall, or the snowflakes/raindrops will be much larger. If there are lots of dust particles, more or smaller snowflakes/raindrops will be able to fall
Extensions
CoCoRaHS Extension Ideas:
In the summer, while you are recording your rainfall data for CoCoRaHS, take care to wash your rain gauge very well before placing it back for the next day’s collection. After it rains, record the amount of rainfall, then pour the water into a white bowl or plate and allow it to evaporate. After it evaporates, observe the bowl and discuss where the small particles now present in the bowl came from.
This can also be done using snow, but be sure to collect clean-looking snow that has freshly fallen; otherwise, dust and dirt can collect from human activity near the snow pile.