Homemade Rain Gauge

[90 Minutes]

Meteorologists are scientists who study and predict the weather. They use many different tools and instruments to record and forecast the weather. Rainfall is measured by a rain gauge. A rain gauge is usually a funnel-shaped collector that fits inside a tube. Make your own rain gauge and measure the rainfall in your area.

You'll need:

• pint-sized plastic bottle (a 1 or 2-liter bottle will also work) • waterproof tape such as duct tape or electrical tape • permanent marker • sharp knife or scissors (ADULT SUPERVISION) • ruler

What to do:

1. If possible, print out these directions. Read them through with your child.
2. With your child, gather everything you'll need.
3. Together, look at the plastic bottle and find the spot where the bottle begins to widen. Help your child cut across the bottle about 1 inch below this point.
4. Take the top part off and remove the lid. Turn the top upside down and fit it into the opening that you just made. (You have created an inside funnel that keeps the rain from splashing back out.)
5. Help him tape the edges together securely.
6. Using the ruler, mark the sides of the bottle, from the bottom up, in 1-inch divisions. Use the permanent marker to mark the measurements.
7. Place the rain gauge outside in an open area and measure the rain as it collects.

How to use:

1. Make more than one rain gauge and place them in different places during the same rainy day. Did they all measure the same amount of rain during the same time period?
2. If they didn't, think about the placement of the gauge. Did you place it near a tree or a building? Did something block the rain's path from reaching the gauge, or was your gauge faulty in some way?
3. You and your child may wish to create a chart of your rain gauge data. Decide if you would like to measure the rain every half hour or every hour.
4. Record notes of steady rain, larger drops, and light rain. Label the time so that you can compare your notes with the data collected from your rain gauge.
5. You could then compare your measurements with those announced on the weather station.

Let's Talk: Ideas to Explore Together.

• At what time of year do you think we have the largest amount of rainfall?
• At what time of year do you think we have the smallest amount of rainfall?
• Why do we need rain?

Useful information:

The rain gauge is designed to catch water and measure the amount of precipitation. One inch of rain generally means one inch of water over one acre of surface. Meteorologists also measure the intensity of precipitation. To do this, they use radar.