NAMIB DESERT LIVING ON THE EDGE

 

BY NANCY PARSON AND KATHY RACKLEY

CLICK FOR PRINTABLE MAP OF THE SKELETON COAST (125k)

Lesson 1

GEOCAM GROUND TRUTHING

MATERIALS: photos of Skeleton Coast, Shuttle orbit maps, world map, washable overhead markers, hand lens, model of Space Shuttle

1. Space photography is similar to taking any picture. Good lighting, direct aim at the subject, and a clear view of the object to be photographed are essential. Demonstrate this to the class: turn off the lights, turn your back to the class, and leave on the lens cap and ask "Now I am going to take your picture. Is there anything wrong with the way I am doing this?" Discuss the necessity of good lighting, direct aim at the subject, and a clear view of your target.

 2. After discussion of taking pictures in the the room, relate this to taking pictures from the space shuttle. The requirements are the same: good lighting and a clear view of the subject. What do we need to take pictures of the Earth from space? The area you want to photograph has to be in daylight. The weather has to be clear or only a few clouds. The shuttle must be directly over the target area and the cargo bay doors must be open and facing the Earth. Demonstrate this with the model of the shuttle. Define remote sensing.

 3. Hand out orbit maps for STS 57. An orbit map shows the paths of the orbits that a space shuttle flies. This map shows the orbits photographed by the Can Do GeoCam cameras from STS 57 in June, 1993. Direct students to trace one of the orbits on the map. The space shuttle, on this mission, traveled between 28 degrees north and 28 degrees south latitudes. Review latitude and longitude with students. Practice finding latitude and longitude of familiar places.

 4. Hand out photographs. Allow students to freely explore for a few minutes. Discuss possible locations of the photo site. Have students locate the position on the orbit map and world map. These GeoCam photos show the Namib Desert in NAMIBIA on the southwest coast of Africa.

5. Identify the following places that appear on the photograph:

6. Examine the photo and identify the following by labeling on the photograph:

Rocky Formations	Surface Water
Fog	Drainage Patterns
Change in Elevation (draw lines)	Clouds (over land)
Sand Dunes	Evidence of Erosion

7. Discuss what this area might look like if we went there. The photo shows the Skeleton Coast of the Namib Desert on the western coast of Africa in NAMIBIA. Guess why this is called "Skeleton"? You will find out in the next lesson.

Lesson 2

Learning About the Namib Desert

 

Skeleton Coast Picture Library outside link

Using National Geographic, January, 1992, pp. 54-85, answer and discuss the following:

 1. What is the age of the Namib Desert?

 2. Describe 3 sources of water in the Namib Desert.

 3. How often is there water in the rivers? What is the annual average rainfall?

 4. How do Namib elephants differ from elephants that live in other places?

 5. How often do Namib elephants need to drink?

 6. How does the fog form and what part does it play in this ecosystem?

 7. List land forms that you see in the photographs in the article.

 8. List some of the animals and plants that live in the Namib Desert.

 9. What are some of the possible food sources in the desert?

 10. Use the lists in #8 and 9 to draw a Namib Desert food web.

11. List water sources in the desert.

12. Look at the map on page 67. What do the red arrows represent? Blue arrows?

In what direction is the wind blowing? What direction does the ocean current flow?

13. How do these animals adapt to surviving in the desert: giraffes, spiders, dune ants, lizards, tenebrionid beetles, people, lions.

 

For additional information: Also see the National Geographic Video - Survivors of the Skeleton Coast

Vocabulary list

• adapt
• detritus
• desert
• ecotype
• poacher
• thermoregulating

  Extension

• Prepare a debate about whether or not a desalinating plant should be built in this desert.
• What impact would available fresh water have on the ecosystem of the Namib Desert?
• Look at the issue from the points of view of conservationists ground water and developers.

Lesson 3

MEASURING THE DEW POINT

PROBLEM:

How can students determine dew point ?

MATERIALS: thermometer shiny can stirring rod room temperature water ice

PROCEDURE:

 Note: You may want to draw a chart to record your data.

 1. Half fill a shiny can with room temperature water. Be sure that the outside of the can is dry when you begin.

 2. Record the temperature of the air and water.

 3. Leave the thermometer in the can. While carefully watching the outside of the can, gradually add ice, stirring with the stirring rod (DO NOT USE THE THERMOMETER TO STIR...IT MIGHT BREAK!). Beads of moisture will appear on the outside of the can giving it a frosted appearance. As soon as moisture appears on the outside of the can, read the thermometer and record. This temperature is the dew point for present conditions.

 4. Repeat the experiment two more times. Always start with room temperature water and a can that is dry on the outside. Record your results.

 5. Find the average of your results.

QUESTIONS:

1. Define dew point.

 2. Define condensation.

 3. What caused moisture to form on the outside of the can?

 4. Do you think the dew point will vary under different conditions? Explain.

 5. Did everyone in the room get the same dew point? Did you get the same in each of your 3 trials? Why would all the answers be the same? Why would they be different? Discuss.

EXTENSION: When would you expect dew to form in the Namib Desert?

Lesson 4

Interpreting the Photo

 PROBLEM: Animals and plants live in the Namib Desert where it rains only about every decade. There is no surface water in the desert. How do plants and animals survive without rainfall?

Use the photo and maps to work through this sheet to help you solve the problem.

1. Use a map to locate the exact position of the photo. Identify the following:

• continent
• country
• large body of water
• latitude and longitude

2. Examine the photo and identify the following by labeling on the photograph (use a washable overhead marker on laminate or plastic overlay):

surface water fog change in elevation sand dunes beach

rocky formations drainage patterns clouds (over land) evidence of erosion surf

Map of Currents

CLICK FOR SMALL MAP OF AFRICAN ATLANTIC CURRENTS

CLICK FOR PRINTABLE MAP OF MAJOR WORLD CURRENTS

3. Using the map, " Major World Currents", identify the current along the Namib coast. Where does this current come from? Is it a warm or cold current? Identify the current to the west of this current. Is it a warm or cold current?

4. Fog - What kinds of conditions over the ocean are needed for evaporation?

• Where does evaporation occur?
• What kinds of conditions are needed for water vapor to condense?
• Where does condensation occur?
• Summarize: what causes fog in the photo to form over the ocean?

In this photo, winds blow from west to east. What effects do the winds have on the fog? How does this relate to our problem of survival without rainfall?

5. What may have caused the drainage and erosion patterns in the photo?

 6. Is there any evidence of people living in this area? Why do people live or not live here? What are some ways that plants and animals could adapt to this environment?

 7. In summary, describe the effect the fog has on the ecosystem of the Namib Desert?