1. L.O: SWBAT explain why we use topographic maps.

2. Do Now: Who remembers why the Earth is NOT FLAT AND SMOOTH?

3. Earth has high places (mountains & hills) and flat places (plains).
L.O: SWBAT explain why we use topographic maps.

4. L.O: SWBAT explain why we use topographic maps.
Earth “holes” in it ( valleys and canyons)!
Earth also has rivers and streams!
L.O: SWBAT explain why we use topographic maps.

5. L.O: SWBAT explain why we use topographic maps.
Topographic map Prefix : Topo: location or place Suffix: Graphic: picture Think Pair Share (1 minute) Based on the pictures below and the hints above make observations about the map or make an inference about what it could be used for?
L.O: SWBAT explain why we use topographic maps.

6. Topographic Maps
Two dimensional model of the Earth’s surface (represents 3-D world)
Topographic maps are also known as
contour maps.
Show elevation above sea level using
contour lines.

11. L.O: SWBAT explain why we use topographic maps.
How to read a topographic map:
L.O: SWBAT explain why we use topographic maps.

12. A contour map shows differences in elevation from one location to another by using contour lines.

13. Contour Lines Several contour lines make up a contour map.
A contour line is a line that connects points of equal elevation.
Several contour lines make up a contour map.
Every point along a given contour line has the same elevation.
100 ft

14. Two contour lines never cross because they connect points of equal elevation.
Overall contour lines show elevation AND show the shape of the land

15. L.O: SWBAT explain why we use topographic maps.
Point to the contour lines then write contour line on or next to line 0,10,20,30
Contour line
Contour line
Contour line
Contour line
Contour line
L.O: SWBAT explain why we use topographic maps.

16. Contour Interval Contour Interval = ??? 50 ft
The difference between two neighboring contour lines is called the contour interval.
100 ft
Contour Interval = ???
50 ft
150 ft

17. Contour Interval Rule: MUST be equal spacing(numbers).
20 feet
580
560
540
520

18. What is the contour interval here?
L.O: SWBAT explain why we use topographic maps.

19. To make reading easier, every 5th line is drawn thicker and the elevation is recorded. These darkened contours are called INDEX CONTOURS.

20. How can we figure out the contour interval if we’re only given index contours?
Step 1: Find the difference in elevation between the two index contours

21. Step 2: Determine how many contour lines you cross from the 1st index contour to the next. Note we do not include the line we start on but we do include the line we finish on. 

22. Step 3: Divide the elevation difference by the number of lines and you get the contour interval. 
Step 4: Check your work! Count up by the contour interval and see if you reach the correct value when you get to the index contour

23. Based on the index contours on the map, what is the contour interval?
Step 1: = 100m
Step 2: 5 lines
Step 3: 100/5 = 20 m
Step 4: check
780
760
740
720

24. Only elevation of points that lie directly on contour lines is known exactly. Any point between the lines has an elevation somewhere between the value of the lines.

25. Using the topographic map above, determine the elevation for the following locations:

26. Contour lines never cross
Rules for Contours
Contour lines never cross

27. 2. Contours form closed loops (even if not shown on the map).
Rules for Contours
2. Contours form closed loops (even if not shown on the map).

28. Rules for Contours
3)The maximum possible elevation for a hill is “1” less than what the next contour “should” be.
The highest possible elevation of the hill is just below the value of  the next line that is not shown 80 70 60 50

29. Let’s Practice some more!

30. 1) WHAT ARE THE INDEX CONTOURS?
700&800
2)WHAT IS THE CONTOUR INTERVAL? 20
3)WHAT IS ONE POSSIBLE ELEVATION OF A?

31. L.O: SWBAT explain why we use topographic maps.
American Soldiers use topographic maps to plan battle strategies.
Topographic maps help the Opportunity probe explore the Planet Mars.
L.O: SWBAT explain why we use topographic maps.

32. L.O: SWBAT explain why we use topographic maps.
Buildings can’t be built properly if we don’t understand the topography of the land.
L.O: SWBAT explain why we use topographic maps.

33. Exit Ticket!
What are the contour indexes
What is the contour interval?
What is the highest contour line
What is the lowest contour line
What is the highest elevation on this map?*hint its not 600*
What is the elevation of A and C?

34. L.O: SWBAT explain why we use topographic maps.
Tomorrow, you will learn how different gradients (slopes), holes and rivers are represented on a topographic map
L.O: SWBAT explain why we use topographic maps.