Lab 6: Why Keep an Eye on the Barometer?
The lab activity described here was created by Martos Hoffman and LuAnn Dahlman of TERC for the EarthLabs project.
Summary and Learning Objectives
Students graph the relationship between air pressure and wind speed in 2005's Hurricane Katrina and for the entire 2005 hurricane season. From their analyses, they come up with an estimate of the minimum air pressure that is likely to result in hurricane-force winds of 65 knots or higher.
After completing this investigation, students will be able to:
- Use a spreadsheet application to generate linear graphs and scatter plots of air pressure versus wind speeds.
- Interpret and compare graphs from a single hurricane and an entire hurricane season.
- Describe the relationship between air pressure and wind speed.
Context for use
Ideally, students would explore this relationship and master the analysis techniques early in the hurricane season so that they could monitor air pressure in tropical storms and make predictions about wind speeds. The activity requires a computer with a spreadsheet application plus access to a printer or electronic portfolio for students to save their work. Part A takes about 25 minutes and Part B & C take about 20 minutes.
Activity Overview, Teaching Materials, and Answer Sheet
Students use a spreadsheet application and the Hurricane Katrina Data (Excel 2007 (.xlsx) 12kB Aug6 18) file to explore how air pressure and wind speed changed over time during Hurricane Katrina. They create a linear graph to illustrate how pressure and wind speed changed as Katrina went from a tropical storm to a hurricane and back to a tropical storm again. In Part B, students generate a scatter plot between pressure and wind speed for Katrina and for the entire 2005 Atlantic Hurricane (Excel 2007 (.xlsx) 33kB Aug6 18) season. They add a trendline to quantify the relationship between the two variables. From their analysis, students estimate the minimum air pressure reading likely to result in hurricane-force winds and evaluate the validity of the quantitative relationship.
You may want to provide a hard copy of the activity sheet (Acrobat (PDF) 49kB Sep20 07) on which students can record their answers. A word processing version (Microsoft Word 2007 (.docx) 22kB Aug6 18) of the activity sheet is also available should you wish to modify or add any questions. Finally, a
- Activity Sheet (PDF (Acrobat (PDF) 49kB Sep20 07) and Word (Microsoft Word 2007 (.docx) 22kB Aug6 18))
- Hurricane Katrina Data (Excel 2007 (.xlsx) 12kB Aug6 18)
- 2005 Atlantic Hurricane Season Data (Excel 2007 (.xlsx) 33kB Aug6 18)
Teaching notes and tips
None to offer until testing is completed
Student-produced graphs, scatter plots, and interpretive descriptions will allow both students and teachers to assess learning.
State and National Science Teaching Standards
Any difference in atmospheric pressure between two locations results in wind. Air always moves from an area of higher pressure toward an area of lower pressure. Further, the greater the difference in pressure, the faster the air moves. Thus, pressure (specifically the relative difference in pressure) is the fundamental control of wind.
This activity builds quantitative skills. One of the primary methods to explore the relationship between datasets is by graphing them. Students graphically discover the quantitative relationship between air pressure and wind speed by creating two different types of graphs. Further, they have opportunities to evaluate the accuracy of the relationship they discovered.