NOVA

Chasing El Niño

Student Handout

Forecasting Folklore

Centuries before meteorologists had advanced technology for making weather forecasts, people observed the natural world and looked for patterns to help explain and predict weather. Many of these observations were turned into sayings and passed down through generations. For example, "The louder the frog, the more the rain," or "A sunny shower won't last an hour." But how accurate is weather folklore? Find out by designing an experiment that puts it to the test.

Cow illustration

A cow with its tail to the west makes weather best; a cow with its tail to the east makes weather the least.

Guiding Steps and Questions
Use these steps to help you design your experiment.

  1. Select a Folklore Saying

    • Evaluate whether the folklore saying can be tested through scientific investigation.

    • What constraints must you consider (such as availability of time and space, limitations of equipment, cost, safety issues)?

  2. Create a Question

    • Change the folklore saying into a question that can be answered through scientific investigation.

    • What do you predict will be the answer to your question and why?

  3. Design the Experiment

    • Identify the variables in the experiment.

    • What kinds of data will help you answer your question?

    • What data will you use to support your prediction?

    • How will you collect, record and represent your data?

    • What materials will you need?

    • What steps will you take to carry out the experiment?

    Ants illustration

    When ants travel in a straight line, expect rain; when they scatter, expect fair weather.

  4. Review the Experimental Design

    • Have another team review your experimental design. What questions do they raise and how might you address them? If there is any part of your experiment you are having a problem with, ask the other team for input or advice.

    • Have your teacher review and approve your experiment before proceeding.

  5. Do the Experiment

    • Record the actual steps you take to carry out the experiment.

    • Record your data.

  6. Analyze the Data

    • What patterns do you see in the data?

    • How do you interpret the data? What evidence supports your interpretation?

    • What might be inaccurate about your interpretation?

    • How else can you explain the data? List two alternative explanations.

    • How can you organize the data to present the strongest explanation for your conclusion?

    Leaves illustration


    When leaves show their backs, it will rain.

  7. Reflect on Your Experiment

    • Identify some of the flaws in your experimental design. How would you change your experiment if you were to repeat it?

    • What new questions do you have after doing this experiment?

  8. Share Your Findings and Interpretations

    • First share your experimental design and then have your fellow classmates predict what they think you found.

    • Next, share your data with them and have them try and interpret what you found.

    • Finally, share your own conclusions and discuss any differing views as a class.

A Sample of Weather Folklore

  • Red sky at night, sailors delight. Red sky in the morning, sailors take warning.

  • The louder the frog, the more the rain.

  • A sunny shower won't last an hour.

  • When doors and windows stick, it will probably rain.

  • A wind from the south has rain in its mouth.

  • Haloes around the sun or moon indicate a rain or snow real soon.

  • When a cow endeavors to scratch his ear, it means a rain shower is very near. When he thumps his ribs with an angry tail, look out for thunder, lightning and hail.

  • Crickets are accurate thermometers; they chirp faster when warm and slower when cold.

  • High clouds indicate fine weather will prevail; lower clouds mean rain.

  • When clouds look like rocks and towers, the Earth will be refreshed by showers.




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