Understanding Geography: Map Skills and Our World - Level 452

11 Climate and Precipitation

When you were little you probably learned these rhymes: “It’s raining, it’s pouring, the old man is snoring,” and, “Rain rain, go away, come again another day.”

Rain is one form of precipitation. Precipitation is the moisture that falls to the Earth. Rain, snow, sleet, and hail are all forms of precipitation. Precipitation is an important part of a region’s climate. Climate is the pattern of weather in a place over a long time.

Some places get more precipitation than others. For example, a rain forest gets more than 100 inches of rain each year—enough to fill a normal room from floor to ceiling. But a desert gets less than ten inches of rain each year—not even enough to reach your knees. Some areas of the world get a lot of rain in one season but very little rain during the rest of the year. In other areas, precipitation falls a little at a time all year long.

The amount of rain a place gets makes a big difference in its plant life. Places that get very little rain have fewer plants than places that get a lot of rain. More kinds of plants and trees grow in tropical rain forests than anywhere else on Earth.

Key Words: precipitation, rain forest, desert, climograph

A rainforest in central Afr ica

People adapt to dr y climates in Afr ica by building huts made of earth and grass.

Wildebeests roaming the dry, hot plains of southern Africa

53Understanding Geography: Map Skills and Our World - Level 4

The map below shows amounts of precipitation in Africa. The precipitation in Africa is mainly rainfall. The map shows the average precipitation in each year in different parts of Africa.

1. The word Sahara means “desert.” What color is the Sahara on the map? Find that color on the map key. How much rain does this region get?

2. Find the Democratic Rebublic of the Congo, near central Africa. How much rain does the city of Kinshasa get?

3. Find Libya in northern Africa. How much rain does Tripoli get?

4. Find Kenya in eastern Africa. How much rain does Nairobi get?

5. Next to Kenya is Somalia. How much rain does Mogadishu get?

6. Find Liberia on the west coast of Africa. How much rain does Monrovia get?

7. On the map, do you see many cities in the Sahara? Why not?

SOUTHSUDAN

Understanding Geography: Map Skills and Our World - Level 454

Graphs and ClimographsA graph can show information about the climate of a place. For example, the graph below tells you about precipitation in three African cities.

On the left, you see the number of inches of rain. On the bottom, you see the months of the year. The black line is for Cairo, the pink line for Johannesburg, and the yellow line for Lagos. Use the graph to answer these questions.

8. Which city gets the least rainfall?

9. Which is the rainiest month in Lagos?

10. About how many inches of rain does Johannesburg get each January?

11. Find the three cities on the map on page 53.

20

15

10

5

0

Inch

es

of

rain

MonthsJa

nuar

y

Febr

uary

Mar

chApr

ilM

ayJu

ne July

Augus

t

Sept

embe

r

Octob

er

Novem

ber

Decem

ber

Cairo, Egypt

Johannesburg, South Africa

Lagos, Nigeria

Annual Precipitation in African Cities

The modern city of Johannesburg, South Africa

55Understanding Geography: Map Skills and Our World - Level 4

Look at the climographs above for the cities of Cairo and Lagos. Red dots show temperature, while blue bars show precipitation.

12. Based on a quick look at the blue bars, which city would you say is in a desert?

13. In which city does the temperature vary more between cooler and warmer?

14. Based on the average temperatures, which city would you say is closer to the equator?

15. In which three months does Lagos usually receive the most rain?

16. Cairo receives very little rain. Where do you think the people get their water? (Look at the map on page 53. Pay attention to the rivers.)

Skill Builder

Review1. Rain, snow, and sleet are forms of .

2. More kinds of plants and trees grow in than anywhere else on Earth. These places get more than 100 inches of rain each year.

3. The Sahara is an example of a , a dry place that gets very little rain.

4. Name two things a climograph can show you.

Try It YourselfGo to www.weather.com. Enter your city or a city near you. Search for information about your city, such as average temperature and rainfall. Choose another city anywhere in the world that you would like to visit. Enter this city’s name in the website and compare its data to the data for your city.

There is a special kind of climate graph called a climograph. A climograph usually shows the average temperature and precipitation in a certain place during a year.

Climograph ofCairo

Climograph ofLagos