Relief in Africa and the World
Senior 3 · Geography
Relief in Africa and the World
Lesson 1 of 4
25 min
Let's begin
From Cape Agulhas at the southern tip of Africa to Ras ben Sakka on the Tunisian coast is about 8,000 km: farther than from Kigali to London (about 6,600 km). Rwanda, which you studied closely in S2, is a small part of this huge continent. This unit widens the view: first to Africa as a whole, then to the other continents. We begin with three questions a geographer asks about any continent: where is it, how big is it, and how many people live there?
Figure 1. Africa and the other continents. Drawn by Ganzaa from Natural Earth data.
Definition
Continent: one of the very large land masses of the Earth. In the seven-continent model they are Asia, Africa, North America, South America, Antarctica, Europe and Oceania (Australia and the Pacific islands).
Absolute location: the position of a place given by latitude and longitude, e.g. Cape Agulhas at 34°51′S, 20°E.
Relative location: the position of a place described by what lies around it, e.g. "Africa lies south of Europe, across the Mediterranean Sea".
Figure 2. Africa's position and its four extreme points. Drawn by Ganzaa from Natural Earth data.
| Extreme point | Place | Position |
|---|---|---|
| Northernmost | Ras ben Sakka, Tunisia | 37°21′N |
| Southernmost | Cape Agulhas, South Africa | 34°51′S |
| Westernmost | Cap-Vert, Senegal | 17°31′W |
| Easternmost | Ras Hafun, Somalia | 51°27′E |
Absolute location. Mainland Africa stretches from about 37°N to 35°S and from about 17°W to 51°E. That is roughly 8,000 km from north to south and 7,400 km from west to east.
Relative location. Africa is bordered by the Mediterranean Sea to the north, the Atlantic Ocean to the west, and the Indian Ocean and the Red Sea to the east. It is joined to Asia only by the narrow Isthmus of Suez, now cut by the Suez Canal, and it is separated from Europe by the Strait of Gibraltar, about 13 km wide at its narrowest.
The great lines of the globe. The Equator, the Tropic of Cancer, the Tropic of Capricorn and the Prime Meridian all cross Africa. Because the Equator runs almost through its middle, most of Africa lies between the two tropics: it is the most tropical of the continents. Rwanda lies just south of the Equator, between about 1° and 3°S.
Tip
Two ways, every time. When an exam question says "describe the location of…", give both: the absolute location (latitudes and longitudes) and the relative location (seas, oceans and neighbouring continents).
Figure 3. Area and population of the continents. Drawn by Ganzaa.
| Continent | Area (million km²) | Population, 2023 (millions) | Density (people per km²) |
|---|---|---|---|
| Asia | 44.6 | 4,777 | 107 |
| Africa | 30.4 | 1,480 | 49 |
| North America | 24.2 | 609 | 25 |
| South America | 17.8 | 433 | 24 |
| Antarctica | 14.2 | no permanent population | 0 |
| Europe | 10.0 | 747 | 75 |
| Oceania | 8.5 | 46 | 5 |
| World | 149.7 | 8,092 | 54 |
Africa is the second largest continent (about 20% of the world's land) and the second most populous (about 18% of the world's people), after Asia in both.
Definition
Population density: the average number of people living on each square kilometre of land.
Example: Africa, people per km².
Worked example
Worked example 1: Africa's share of the world. Use the table to find the percentage of the world's land area and of the world's population that Africa has.
Answer: about one fifth of the land and a little under one fifth of the people.
Worked example
Worked example 2: Africa and Rwanda. Rwanda covers 26,338 km² (Rwanda Development Board). The 2022 census counted 13,246,394 people, a density of 503 people per km² (NISR). (a) How many times larger than Rwanda is Africa? (b) Compare the two densities.
Warning
Averages hide the pattern. A density of 49 per km² does not mean people are spread evenly over Africa. Millions crowd the Nile valley and delta, the coasts of West Africa and the East African highlands, while large parts of the Sahara and Kalahari have almost nobody. Also note that the area and population figures in the table come from different sources, which draw some continental boundaries (for example across Russia and the Middle East) slightly differently, so the densities are approximate.
Practice
Sources and credits
Figures 1 to 3, the worked examples and the practice exercises are written by Ganzaa.
This lesson adapts CC BY-SA material and is shared under CC BY-SA 4.0.
