1. Understanding Isobars This slide show helps you learn how to draw the isobars (lines of equal pressure) around high and low centers. It also shows the ways in which winds blow.

2. ISOLINE ACTIVITY: 1.In PEN, uncode each pressure: -If 500 or greater at a 9 to the front of number. Ex. 980 = 998.0 -If 499 or less then add a 10 to the front of number. Ex. 103=1010.3 2.In PENCIL, label the highest pressure H and the lowest pressure L. 3. For the H draw the following isobars: 1016, 1012, 1008 mb 4. For the L draw the following isobars: 996, 1000, 1004 mb 5. For each wind indicator- show wind movement.

4. H L 1016 mb

5. H L 1012 mb 1016 mb

6. H L 1008 mb 1012 mb 1016 mb

7. H L 996 mb 1008 mb 1012 mb 1016 mb

8. H L 996 mb 1008 mb 1012 mb 1016 mb 1000 mb

9. H L 1004 mb 1000 mb 996 mb 1008 mb 1012 mb 1016 mb

10. H L 1004 mb 1000 mb 996 mb 1008 mb 1012 mb 1016 mb

11. Follow up questions: 1.Describe the wind motion in the H. 2.Describe the wind motion in the L. 3. In what area is the wind speeds the greatest? 4.Winds go from ___ to ____ for pressure.

12. Summary

13. Go to the following website and follow the directions on how to draw isobars on the map. Draw the lines, as drawn on the website, on a copy of the map that you will need to paste into a PowerPoint presentation of your own. http://www4.uwsp.edu/geo/faculty/ritter/geog101/textbook/manuals/in structor_manual/how_to/drawing_isobars.html Do the following on your PowerPoint presentation. 1.Slide one should have a title with your name. 2.Slide two needs to have the answers to the four questions that were on my slide 11. 3.For slide 3, copy the map from my slide 14 and paste it in your PowerPoint as slide 3. If that does not copy, click on the assignment labeled “Isobar Map” from my assignment page. 4.Follow the directions from the website above and continue drawing all of the isobars on the entire map with the tools at the top of the screen, under the home tab.