Evaluation copy. Air Temperature Measurements. computer OBJECTIVES MATERIALS PRE-LAB QUESTIONS

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1 Air Temperature Measurements Computer P1 An important factor in our weather is the difference in temperature of the air. A good example of this relationship is the production of land and sea breezes along the coast of an ocean. These winds occur because of the difference between the temperature of the air above ocean compared to the air above the land. Another example comes from understanding the formation of some clouds. The air next to different patches of ground heats up differently. Air next to hot land surfaces becomes warmer, which causes it to rise, expand and cool to form cumulus clouds. In this experiment you will investigate local changes in air temperature over a 23 hour period. You will do this with two temperature probes-one near the ground and the other one meter above the ground. OBJECTIVES In this experiment, you will Use Temperature Probes to collect and analyze air temperature measurements for 23 hours. Collect and analyze air temperature measurements at different heights above the ground. MATERIALS computer Vernier LabPro Logger Pro PRE-LAB QUESTIONS 2 Temperature Probes 1.5 m metal rod 2 right angle clamps 1. Sketch a graph of air temperature for a 24 hour period. Predict what hour of the day you would expect to be the hottest, the coldest. Evaluation copy 2. Would you expect the air temperature right next to the ground to be colder or hotter than the air above the ground? Would you expect this difference to be the same throughout the day? Explain your reasoning. Earth Science with Vernier P1-1

2 Computer P1 3. Use an almanac, the weather forecast, or the Internet to determine when sunrise and sunset will occur during the experiment. Enter those times into the data table. PROCEDURE Note: You must use Logger Pro software and a LabPro to collect data remotely. Logger Lite and Go! products do not support remote data collection. Day 1 1. Connect the temperature probes to LabPro and make sure that fresh batteries have been installed. Start Logger Pro and open the file P1 Air Temperature from the Earth Science with Vernier folder. 2. Choose Remote LabPro Setup from the Experiment menu. A summary of your setup will be displayed. Figure 1 3. Disconnect the computer cable from LabPro. Important Note: Be very careful not to press the START/STOP button on LabPro until you are ready to begin collecting data. 4. Carry the LabPro, temperature probes, and metal rod outside. Choose a location that will be in the shade throughout the daylight hours. Push the metal rod into the ground so it is straight up and down. 5. Use a right angle clamp to secure Temperature Probe 1 near the ground. Use another right angle clamp to secure Temperature Probe 2 one meter above Temperature Probe Press the START/STOP button to start data collection. Record the time of day to the nearest hour in the data table. Enter the time using a clock format of hour and AM or PM, for example 11:00 AM. Day 2 7. At the end of 23 hours, collect the LabPro, sensors, and metal rod and take them back to the computer. Note: Do not attach LabPro to the computer until Step Start Logger Pro and open the file P1 Air Temperature. 9. Reattach LabPro to the computer. If a Remote Data Available window appears, simply click the YES button and choose to retrieve remote data into the current file. If a window does not appear when the interface is reconnected, choose Remote Retrieve Remote Data from the Experiment menu. P1-2 Earth Science with Vernier

3 Air Temperature Measurements DATA Sunrise Sunset Time of day that data collection began Hour from Start (hr) Time of Day (Hour AM/PM) Temp 1 Temp 2 Degrees Warmer Temp 1 near ground Temp 2 above ground Earth Science with Vernier P1-3

4 Computer P1 PROCESSING THE DATA 1. The first row in the data table corresponds to the time when the experiment began. Enter that time in the first cell of the Time of Day column. Read the temperatures for the two probes and record them in the next two columns of the data table. Round the temperatures to the nearest tenth of a degree, for example Continue to fill the data table in with the time of day for each row of the data table and the corresponding temperatures. Remember that the Time of Day column uses a clock format and after you reach 12:00 AM, you will have to switch to 1:00 PM. 3. For each hour, examine the temperature data and determine which was warmer, the air near the ground (Temperature 1) or the air that was one meter above the ground (Temperature 2). Calculate the temperature difference and record the difference in the appropriate column of the data table. For example if Temperature 1 is 20.3 and Temperature 2 is 20.9, enter 0.6 in the Temperature 2 column. 4. At what hour was it hottest during the day? When was it coldest? 5. Describe in one or two paragraphs the relationship that you observe between the temperature next to the ground and the temperature one-meter above the ground. The following questions might help you prepare your answer. Were the temperatures different for the entire 23 hours? If the temperatures were different, was one temperature always higher than the other temperature? Were there times when the temperatures were the same or close to being the same? What is the general relationship between these two temperatures? EXTENSIONS 1. Are the patterns that you observed repeatable? To answer this question, set up the experiment to collect data for two to three days. Compare the data from one day to the next. 2. Repeat the same experiment but use three or four temperature sensors and place one probe even higher above the ground. 3. Repeat this experiment at different times of the year. If you live in a snowy climate, you may want to repeat the experiment when snow is on the ground. P1-4 Earth Science with Vernier

5 Vernier Lab Safety Instructions Disclaimer THIS IS AN EVALUATION COPY OF THE VERNIER STUDENT LAB. This copy does not include: Safety information Essential instructor background information Directions for preparing solutions Important tips for successfully doing these labs The complete Earth Science with Vernier lab manual includes 33 labs, 6 projects, and essential teacher information. The full lab book is available for purchase at: Vernier Software & Technology S.W. Millikan Way Beaverton, OR Toll Free (888) (503) FAX (503) info@vernier.com