3. General Instructions
• Slide Show is required to teach.
• Students must keep their microphones off/mute while the
teacher is teaching.
• Students can unmute their microphones to answer the
question asked by the teacher.
• The teacher may also use lolly sticks.
• Answers in the following slides are animated based on
mouse clicks.
• Prior preparations: Reference materials to be downloaded
and/or to be used in sync with lesson presentation, shall
be kept open and minimized.
• Home assignment and homework worksheet to be solved
and uploaded in the Google classroom.
4. Learner's Outcome
Period 1
Sub-topic:
• Tropical Desert – Sahara: climate, natural
vegetation
The students will be able to:
• discover the climate, natural vegetation, of the
tropical desert Sahara
9. The deserts are barren lands, they are
characterized by extreme
temperatures, less annual rainfall and
scanty vegetation.
In this period, we shall study about:
• Tropical Desert – Sahara: climate,
natural vegetation
10. Has anyone of you ever visited
any desert? If yes, then share
your experience.
11. State any two feature of Tropical
Desert Vegetation.
12. In these areas, heat is oppressive and
rainfall is scanty. Mostly shrubs occur
in patches. The plants consist of long
roots, thick stems, thorns and wax
coated leaves. Loss of moisture is
prevented by these features. The
important plants are cactus, thorny
bushes, date palms and coarse
grasses. On the margins of desert,
some acacia trees are also found.
13. The Sahara Desert
• The Sahara is the
largest hot desert
in the world.
• The Sahara Desert
covers a vast
expanse of nearly 9
million square
kilometres. It is
almost as large as
the USA and nearly
thrice the size of
India.
14. With the help of the political map of Africa in
your atlas, find out the names of the countries
that lie entirely or partially within the Sahara
Desert.
16. Any accumulation of sand grains
shaped into a mound or ridge by the
wind under the influence of gravity is
called dune
17. The Sahara Desert is not a uniform stretch of only dunes as we
usually visualize when the name desert is mentioned. The Sahara is
a sea of sand with shifting dunes.
18. In some parts, we can see crescent-shaped dunes called barchans.
19. In parts of Egypt, the dunes are longitudinal and are called siefs.
20. The dunes grow and creep forward with
the constant movement of the wind in the
same direction.
21. The rest of the Sahara is rugged and rocky with
mountains and plateaus.
22. Lake Chad is the only freshwater lake in this
region.
23. Emi Koussi
Qattara Depression
The highest point of the Sahara desert is Mt. Emi Koussi in Tibesti
Mountain and the lowest point is Qattara Depression.
25. Oases are water sports in the desert-like depressions where the
groundwater is exposed on the surface or natural springs or river,
around which settlements grow up due to opportunity for
agriculture and pastures.
27. Climate
The climate of Sahara is one of
the harshest in the world. It has a
hot and dry climate with
extremes of temperature. After
long intervals, torrential rain of
short durations may fall at
places, but the water disappears
immediately or dries up fast due
to the sandy soil and high rate of
evaporation.
28. Xerophytic plants
In the actual desert areas of the
Sahara xerophytic plants are
found. They have long roots that
tap groundwater. The succulent
stems store food and water.
Leaves are transformed into
spines to reduce the loss of
moisture. Cacti and acacia are
common vegetation.
Natural Vegetation
30. What did you learn today?
• Sahara is the largest and
hottest tropical desert in the
world.
31. Points to remember
• Sahara lies in northern half of Africa.
• The climate of Sahara desert is extremely hot and dry.
• Since water is scarce, plants have developed the ability to
preserve their water.
