for good measure EARTH SYSTEMS using weather measurement devices Frameworks

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1 EARTH SYSTEMS for good measure using weather measurement devices Frameworks SCIENCE NS Verify accuracy of observations. NS Apply components of experimental design used to produce empirical evidence NS Communicate results and conclusions from scientific inquiry NS Interpret evidence based on observations. NS Analyze components of experimental design used to produce empirical evidence NS Communicate results and conclusions from scientific inquiry ESS Identify the elements of weather: temperature, air pressure, wind speed and direction, humidity. ESS Conduct investigations using weather measurement devices: anemometers, barometers, sling psychrometers, thermometers, weather charts. NS Justify conclusions based on approprate and unbiased observations. NS Evaluate the merits of empirical evidence based on experimental design LANGUAGE ARTS W Write across the curriculum. W Write across the curriculum. W Write across the curriculum. s Objectives The students will learn: Objective #1 To identify and use weather measurement devices. Objective #2 To record and interpret observations. Objective #3 To determine that certain weather elements influence gardening decisions and tasks. Objective #4 To build simple weather measurement devices (if applicable). Objective #5 To appropriately use verbal speaking skills in class discussion with the teacher and Garden Program Specialist.

2 Page 2 EARTH SYSTEMS For Good Measure: Teachers Guide Measuring and interpreting elements of weather correctly will enhance proper care and maintenance of the garden. Overview Weather consists of four basic elements: air temperature, air pressure, wind direction and speed, and humidity. Each is measured with specific tools. Garden Activities Building simple weather measurement devices (if applicable) Measuring elements of weather elements using appropriate devices Identifying how gardening tasks are affected by current weather Performing weather-appropriate gardening tasks Recipes and Taste tests as time permits (refer to Delta Garden Study Recipe Book)

3 EARTH SYSTEMS For Good Measure: Teachers Guide Page 3 Tips for THE CLASSROOM Pre-lesson preparation: 1. Check with Garden Program Specialist to discuss the availability of weather measuring instruments. 2. Determine an appropriate data table for students to create according to the weather data they will be collecting. You may want to include basic observations, such as rain, clouds in the sky, etc. LESSON OUTLINE classroom materials needed Student Workbooks in the garden in the classroom activities estimated duration actual duration Offer the icebreaker 5 minutes Explain and discuss the types of 10 minutes weather measuring instruments in the garden back in the classroom Instruct students to measure different weather elements with either homemade or purchased models Perform weather appropriate gardening tasks Explain the importance of collecting and recording results of weather measurements during the activities. Hand out Student Workbooks, review and assign Take it Home Activity as homework 10 minutes 15 minutes 5 minutes Tips for THE GARDEN Pre-lesson preparation: 1. Prepare the weather scavenger hunt in the garden. Set up various (purchased or built) weather measuring instruments at three different stations that provide varying readings (e.g. the greenhouse, a sunny spot in the garden, a shady spot in the trees, etc.). Garden tools 2. Prepare to discuss how weather observations indicate planning or maintenance of the garden, and which plants thrive in the current weather conditions. 3. Prepare a brief weather appropriate garden work activity for students in the garden. garden materials needed Available weather measuring instruments (thermometers, anemometers, rain gauge, etc.)

4 Page 4 EARTH SYSTEMS For Good Measure: Teachers Guide Lesson PLAN I. Start in the classroom A. Icebreaker Ask students: Are men or women more likely to be struck by lightning? Answer: Men are 6 times more likely to be struck by lightning than women. Ask students: What kind of tree is most likely to be struck by lightning? Answer: Oak trees are struck by lightning more than any other tree. B. Present Main Topic Show students available weather measuring instruments. Explain and discuss instruments and how they are used. Ask students to create a data table on the journaling & calculations page of the Student Workbook that is based on available weather measuring instruments. II. Take class to the garden : Optional: Construct any weather measurement device as desired, following the instructions on the Supporting Information for Teachers pages. Divide students into pairs or small groups and conduct a weather scavenger hunt. Have students visit weather stations around the garden. Ask students to record their observations and measurements in the data table they created. Discuss what their observations indicate to the planning or maintenance of a garden. MEETS OBJECTIVES #1, 5 MEETS OBJECTIVE #2 Meets Objective #4 Meets Objective #2 Meets Objectives #2 3 example Strong winds could indicate the need to stake or protect some plants. Or: The hot and dry air makes watering necessary. Or: Low pressure indicates storms, which could bring too much rain. Or: It s mild and sunny, just perfect for overall maintenance tasks. Instruct the students to perform gardening tasks as necessitated by weather conditions. Instruct students to pick and taste available vegetables. Discuss the weather requirements for the crop that was tasted. Ask students if the same crop could be harvested in the middle of July, or the middle of December? Could this crop be grown in a greenhouse? Meets Objective #1 Continued next page

5 EARTH SYSTEMS For Good Measure: Teachers Guide Page 5 Continued from previous page III. Take class back to classroom Hand out the Student Learning Workbook as reference material and class assignment. Review take it home activities and encourage students to do them. Supporting Information for Teachers BACKGROUND During this lesson, students will be conducting a weather scavenger hunt. They will need to create their own data table to record their observations. The data table should be based on the weather measuring instruments that are available for the scavenger hunt. This data table will be used during the next lesson to practice predicting the weather. Therefore, when designing the students data table, also consider the following measurements and how they might be important predictors of weather: Wind speed (if an anemometer is built or available) can help determine how fast or slow a front is moving into an area. Fast moving winds indicate storms or changing weather. Slow to no winds suggest that weather will be steady and unchanging for a while. Wind direction can indicate where a storm or weather front is moving in from. Typically, winds coming in from the north (from polar regions in Canada) bring drier and colder air. Winds from the south and southeast (the tropics and the Gulf Coast) bring moisture and heat. Winds from the west and southwest tend to be warm and dry. Air pressure (if a barometer is available) increasing on a barometer generally indicates that the weather is improving. The skies turn clear and precipitation stops. If pressure is falling, clouds and rain or snow are likely to follow. Rain can sometime be predicted by observing changes that occur around the garden. Here are some rain predictors that might be helpful to document on the data table. Birds are flying low. Bees are not buzzing around and spiders out on their webs. The leaves on trees are curled at their edges or turned over. Flowers smell particularly sweet. Temperature is not necessarily a predictor of weather unless recorded over long periods of time. However, it can be a great predictor for what types of garden activities should take place. If temperatures have been or are predicted to be particularly low, garden beds should be covered and greenhouse thermostats should be set to protect plants from frost. More details concerning weather predictions can be found in the next lesson (Tomorrow s Weather) where students will explore such predictions. Optional: As the teacher, you might wish to include a class project on how to build simple weather measurement devices, as described on the following pages.

6 Page 6 EARTH SYSTEMS For Good Measure: Teachers Guide Anemometer An anemometer is used to measure wind speed to determine how quickly a storm, or weather system, will travel to other areas. Materials needed Five 3-ounce paper cups Hole punch One straight pin Pencil (with eraser) Scissors Stapler Two straight plastic straws Watch with a second hand Procedure 1. Punch one hole in each of four paper cups, about ½ below the rim. Color the outside of one of the cups to distinguish it from the others. 2. In the fifth cup, punch four evenly spaced holes about ¼ below the rim. 3. Push a straw through the hole of the colored cup. Fold down the tip of the straw inside the cup and staple it to the cup on the side opposite the hole. 4. Push the straw through two opposite holes in the four-hole cup. Attach another cup to the opposite end of the straw. Make sure that the second cup faces the opposite direction from the first cup. 5. Repeat the above step with the other two cups and straw. 6. Position the four cups so that they face the same direction clockwise or counterclockwise. Make sure the cups are all the same distance from the center. 7. Poke a hole in the bottom of the center cup. Push the eraser end of the pencil through the hole. 8. Push the pin through the intersection of the two straws. Then push it into the eraser as far as possible. Experiment Have two students pair up. Take the anemometer outside to an open area where the wind is blowing. While one student times exactly one minute on the watch, the other counts how many times the colored cup goes by in one minute. This is the number of revolutions per minute (RPM). Convert your answer for RPM to miles per hour (MPH) using this formula: RPM X = MPH Sling psychrometer A sling psychrometer is used to measure the amount of relative humidity in the air. Relative humidity is the amount of moisture in the air divided by the maximum amount the air can hold. The higher the relative humidity is, the more likely it is to rain. Centrigrade thermometers are set up so that 0 degrees centrigrade equals freezing and 100 degrees centrigrade = boiling. Materials needed 2 centigrade thermometers tape wet gauze rubber band fan Relative Humidity Table, next page Procedure 1. Tape the two thermometers to the surface of a table with the numbers facing up and the liquid filled ends sticking over the edge of the table about 1 inch. 2. Using the rubber band, tie the wet gauze around the liquid filled end of one thermometer. 3. Blow the fan on the thermometers until the temperature stops falling. (Blowing the fan mimics the swinging or whirling motion typically associated with a sling psychrometer.) 4. Record the temperature on both thermometers. 5. Subtract the temperature on the wet thermometer from that of the dry one. 6. Check table on next page. Locate the dry thermometer temperature on the left and follow it to the right. Calculate the difference between the two temperatures on the top, and record it. The number where the row and column intersect is the relative humidity.

7 EARTH SYSTEMS For Good Measure: Teachers Guide Page 7 Relative Humidity Table (in percent) Dry bulb Dry bulb wet bulb in degrees Celsius C Sources Scholastic.com About.com National Oceanic and Atmospheric Administration s National Weather Service National Park Service National Oceanic and Atmospheric Administration Miami Science Museum Make Your Own Weather Station

8 EARTH SYSTEMS for good measure using weather measurement devices study guide for students Every day, we make decisions based on the weather: Will soccer practice be rained out? Can we have recess in the gym or outside? Do I need to wear a jacket? You have probably asked yourself similar questions and have heard your teachers, friends and family members discuss other issues that had to do with the weather. That s why it s important to have accurate measurements and recordings of the various weather elements. The weather, as you recall, is determined by four elements in our atmosphere: air temperature, air pressure, wind direction and speed, and humidity. Each is measured with specific tools. Here is how they work: Air temperature thermometer degrees Air temperature is measured using a thermometer in units called degrees. In the United States, we use degrees Fahrenheit, commonly written as F. On this scale, the freezing point of water is 32 F and the boiling point is 212 F. Outside the United States, the standard scale used to measure temperature is degrees Celsius, written as C. On this scale, the freezing point of water is 0 C and the boiling point is 100 C. You ll need to know how to convert a Fahrenheit temperature to Celsius and vice versa: To convert Fahrenheit to Celsius, subtract 32 from it and then multiply by 5/9: C = ( F - 32) * 5/9 To convert Celsius to Fahrenheit, multiply it by 9/5 and then add 32: F = ( C * 9/5) + 32 Some useful temperature facts: Room temperature is about 70 F or 20 C. Absolute Zero (the coldest possible temperature) for water is F or C. A human s body temperature is usually 98.6 F or 37 C. Continued next page

9 Page 2 EARTH SYSTEMS For Good Measure: Study Guide Air pressure barometer millibars The air in the atmosphere above us has weight and therefore exerts pressure. This pressure changes frequently and brings changes in weather. A barometer measures air pressure. It was first invented by an Italian scientist called Evangelista Torricelli in A barometer in its simplest form consists of a tube partially filled with mercury (a heavy metallic element in liquid form) and turned upside down onto a base. The mercury rises and falls in the tube based on air pressure. Air pressure is measured with a barometer in units called millimeters or millibars or in inches of mercury. Air pressure changes with elevation and air temperature. Air pressure is highest at sea level, which is what we are used to, and decreases as you go up. Cold air is fairly dense and exerts fairly high pressure. Warm air is less dense so it exerts relatively low pressure. Generally, the weather stays fair, with clear skies, or improves if air pressure rises. If the pressure steadily drops, the weather may turn cloudy, rainy or snowy. Wind speed Anemometer An anemometer is a device that measures wind speed. Meteorologists can determine how quickly a storm, or weather system, will travel to other areas based on wind speed. There are many different types of anemometers, but the simplest one is a cup anemometer that you can build yourself. It was first built in Wind direction weathervane Wind direction is measured with a weathervane. Winds are named for the direction from which they blow, so a southerly wind blows from the south. Winds tend to carry weather with them. If you want to get an idea what tomorrow s weather will be like, check out the weather in the area from where the wind is coming. A weathervane will tell you by pointing in that direction. Humidity Psychrometer (rain gauge) Humidity refers to the amount of moisture, or water vapor, in the air. We usually speak of relative humidity, that is, the percentage of moisture the air holds relative to the amount it can hold at a particular temperature. This relative humidity is measured with a psychrometer. A psychrometer consists of two thermometers, a wet bulb and a dry bulb. Comparing the readings, you can determine the relative humidity. You can make your own sling psychrometer. When the relative humidity is 100 percent, it s raining or snowing. On earth, the relative humidity is never 0 percent. Even in the planet s deserts, it is always at least 1 percent. Warm air can hold more moisture than cold air. Rainfall is measured using a rain gauge. On a weather map, the color green indicates rain. humidity refers to the amount of moisture or water vapor in the air psychrometer an instrument that measures relative humidity barometer an instrument that measures air pressure thermometer an instrument that measures temperature meteorologist a person that studies weather anemometer a device that measures wind speed rain gauge an instrument that measures rainfall weathervane also known as a wind vane; an instrument that measures wind direction, the arrow indicates the direction from where the wind is coming

10 class assignment A-B EARTH SYSTEMS for good measure ESS Identify the elements of weather. 1. List 5 instruments for measuring weather and tell what they measure: Why is it important to measure and track weather? Take it Home There are many things you can do inside when it might be raining, snowing, too cold, or sleeting outside. Try turning up the music and dancing tonight in your room for some fun times and exercise.

11 class assignment A-B EARTH SYSTEMS for good measure answer key 1. List 5 instruments for measuring weather and tell what they measure: Answers may vary, but might include: psychrometer relative humidity barometer air pressure thermometer temperature weathervane wind direction anemometer wind speed 2. Why is it important to measure and track weather? Answers may vary.

12 class assignment C EARTH SYSTEMS for good measure ESS Identify the elements of weather. 1. List 5 instruments for measuring weather and tell what they measure: Why is it important to measure and track weather? 3. Describe the types of precautions that should be taken in the garden based on the current seasonal weather conditions. Take it Home There are many things you can do inside when it might be raining, snowing, too cold, or sleeting outside. Try turning up the music and dancing tonight in your room for some fun times and exercise.

13 class assignment C EARTH SYSTEMS for good measure answer key 1. List 5 instruments for measuring weather and tell what they measure: Answers may vary, but might include: psychrometer relative humidity barometer air pressure thermometer temperature weathervane wind direction anemometer wind speed 2. Why is it important to measure and track weather? Answers may vary. 3. Describe the types of precautions that should be taken in the garden based on the current seasonal weather conditions. Answers may vary.