Name: ____________________
GIS Introduction
Geographic Information Systems (GIS) are computerized information systems used to store and
analyze map data. GIS combine data collected from many different sources, including
satellites, topographical maps, photographs and many others. GIS combines data from many
maps to give detailed information about an area. Our goal today is to get an introduction to GIS
so we can continue to use this technology in the future. You will be using two different map sets
for your introduction.
NOTE Bold Items - are background information.
Italicized Items - ask you to manipulate the map in some way.
Questions (paraphrased or restated as part of your answer) and Answers should be recorded in
your journals. Make sure to label Part I and Part II.
____________________________________________________________________________
Part I - Topography and our national heritage
- Interpret the landscape using topographic maps of a well-known national park.
Map URL: http://esriurl.com/earthgeoinquiry1
How did Yosemite inspire the institution of the National Park System?
Investigate the pins that show on the map.
1.
Why is it important to dedicate these areas as national parks?
2. What do the smooth brownish parallel lines around the map represent?
3. What do the blue squiggly lines represent?
4. What type of landform is most visible on the map?
What do the brown contour lines tell us about the landscape?
Use the bookmarks to zoom to Half Dome.
5. Why do contour lines rarely touch or cross?
6. What pattern do contour lines make around the hills and mountains?
When you get to the edge, what does it look like?
Zoom to the El Capitan bookmark
7. What is the pattern of contour lines for very steep areas like this cliff?
Zoom to the Camp Ground – near the Glacier Point bookmark, and turn off the USA Topo Maps
layer. (Press Contents and then uncheck USA Topo Maps).
8. What is your hypothesis if this area does not have concentric circles or parallel lines that are
very close together?
9. What is the elevation of this area in feet?
10. What do index contours have periodically along their lengths that other lines do not?
How do you show tall things on flat paper?
Turn on the USA Topo Maps layer back on.
Zoom back to Half Dome, and then find two index contours closer together, with clearly marked
elevations.
11. How many lines are there between these two index contours?
12. Determine the contour interval.
13. What is the elevation of the contour line directly below the “e” in the label “Half Dome?”
14. Use the Measure tool to measure the distance from the top of Half Dome down to where
the trail meets the river. How far is it?
How difficult would the Half Dome trail be?
15. Looking at Half Dome, which side of the hill would be easiest to climb?
16. Which stream would be less strenuous to hike from the campground: a couple of miles up
Tenaya Creek to the north of Half Dome, or a couple of miles up the Merced to the south of Half
Dome?
Pan south until you find the Merced River.
17. Which way is the stream flowing?
Part II - Using Remote Sensing to Avoid Disasters
- Considering hazards using remote-sensed data.
Map URL: http://esriurl.com/earthgeoinquiry2
What does an area prone to landslides look like?
When the map opens, there are brown lines that show elevation.
1.
What types of maps include this information?
Click Modify Map, and then choose the Hills and Mountains bookmark.
2. What do contour lines look like around hills or mountains?
Click the Steep Hills and Flat Areas bookmark.
3. What is the difference between steep hills and flat areas?
How many people can a landslide impact?
Switch the basemap to Imagery, and click the River bookmark. Zoom and pan around the area,
counting the houses.
4. How many houses were in the area of interest?
Click the Content button.
Turn on the OSO Image After Landslide Layer.
Measure from the top of the slide to the southern edge of the rubble field.
5. How far did the hill move?
Click the Area button, and measure the total area that the slide covered.
6. How far did the slide cover.
Could they have seen it coming?
Several factors may have contributed to the slide. The area had received twice the normal rain
in the prior two weeks.
Turn on the LIDAR data for the Hillside Post Slide layer.
7. How does this change the look of the picture?
8. Can you find other areas in this stretch of river that failed and slid? Make sure to zoom back
far enough….
What part might the river have played in the slide?
Faster moving water erodes better than slower moving water.
9. On a curve, where is the water moving the fastest?
10. What does the river look like directly under the hill that failed?
Switch the basemap back to Topographic.
Zoom in to the hillside that failed until you can read the contour lines.
11. How tall was this hill from the base contour line to the river?
Where is a safer place to live while still staying near the river?
Now that you can see that this area had slides in the past, look for a place along the river that
you think would be safer.
12. Can you find a place where the hills are less steep and river is not present to erode the hill?
(Please list distance and direction from the original Oso site in your answer.)