Purpose: To design, build, and install a rain gauge for the school; design a table for collecting data, and record rainfall throughout the year. Answer the question, What the rainiest month is at your school?
Big Idea: Understanding the amount of precipitation in your area is important for farmers who rely on rain and snow to irrigate their crops. However, a lot of rain must fall in order to water soil well.
Background Information: A simple rain gauge can be made from a straight-sided container made of plastic, glass or metal. It is necessary to have a method of measuring the amount of precipitation that is collected in the container. Therefore, a clear plastic or glass container might be preferred because it can be marked off and labeled on the outside of the container. If the weather is below freezing, it will be necessary to measure and empty these types of containers before they freeze and break. A metal container has the advantage of not breaking when ice forms, but measuring the amount of precipitation becomes more of a challenge.
When small amounts of precipitation fall, the amount collected can be difficult to measure. Specially designed range gauges with larger openings (not straight sided) have been designed and calibrated to meet this challenge. Because rain gauges are relatively inexpensive and can be purchased at local hardware stores, it might be wise to purchase this device for your weather station. The rain gauge is an essential part of the backyard weather station.
Rain gauges measure the amount of rainfall in cubic inches. So your first task is to make a scale for your container that shows how many cubic inches of water are in the container. One cubic inch of water is about 3 1/4 teaspoons, so you can draw the scale on your container by measuring 3 1/4 teaspoons of water to your container, then drawing a short line at the level of the water. If you look closely, the top of the water will seem to be slightly curved and thickened. Draw your line so that it matches the bottom of the curved surface (which is called a meniscus). This line corresponds to a rainfall of one inch.
Teachers: print out the worksheetbelow: one per group.
Design, construct, and install a rain gauge for the school. Create a table for collecting data. Discuss how to collect the data throughout the school year.
Have student groups complete the three questions on the hand out below.
- Clear plastic ruler
- Rubber band
- Transparent tape
- soda bottles
- metal containers of different sizes
- glass containers of different sizes
- plastic containers of different sizes
- hammer and nails
- Discuss as a class what a rain gauge is.
- !n groups, brainstorm ideas for a rain gauge. Consider where and how to install it.
- Reveal the materials, and allow students to design an exact rain gauge.
- Build it!
- Make a chart that will allow you to collect data over the year.
- Why is a rain gauge an important part of a weather station?
- Where is a good location for a rain gauge?
- You will be answering the question, What is the rainiest month at Langley Middle School? How can you determine this with your rain gauge?
- What is necessary to do after each use of the rain gauge?
- How can you factor in weekends?
- How is snowfall measured?
A rain gauge is needed to measure the amount of precipitation that falls in an area. Rainfall is recorded in cubic inches. You will be collecting and measuring rain and answering the question, What is the rainiest month at Langley Middle School?
- Design and construct a rain gauge for the school that will measure the amount of rain that falls.
- Discuss where a good location for the rain gauge is. You will be installing it outside in the school yard. What are some factors to consider when locating your gauge?
- Create a table for collecting the data that the rain gauge will give you. What is the necessary information to record to understand rainfall in your area?
- Why is a rain gauge important for a gardener?
- What factors could be considered for locating a rain gauge?
- You will be answering the question, What is the rainiest month at Langley Middle School? How can you determine this with your rain gauge? (e.g. how often will you check your gauge?