- Position, Shape and Size of Africa
- Major Longitudes and Latitudes
- Rotation of the Earth
- Revolution of the Earth
- Map Reading and Interpretation
- Physical Features
- Climate
Position, Shape and Size of Africa
Position
Africa lies between latitude 37°N and 35°S and on longitute 18°W and 52°E.
Separated by water from all other continent except at the point where it joins Asia.
NOTE; When giving the position start with the latitude and then longitude.
Mostly Easterly point is called ras hafun(cape guardafui)
Mostly westerly is cape verde
Mostly northerly is cape bon
Mostly southerly is cape agulhas
Africa is connected to sinai peninsula by suez canal
Separated from spain by strait of gibraltar
Separated from rabia by strait of bab el-mandeb
Shape
The northern half is very wide while the southern is much narrower
At the cape guardafui extends outwards in the shape of a horn therefore the horn of africa.
Size
Africa is the second largest continent in the world
Has an area of about 30.3 million square kilometres(20% of the total land surface)
It measures 8000 km from north to south and 7400km from east to west
Other continents
- Asia – 43608000km2
- Africa – 30335000km2
- North america – 25349000km2
- South america – 17611000km2
- Antarctica – 13340000km2
- Europe – 10498000km2
- Australia – 8923000km2
Countries of Africa and their Location
Africa has the largest number of countries in the world making a total of 55 countries
The newest country is South Sudan
African countries are given below in alphabetical order:
Algeria 2381741km2
Angola 1246700km2
Benin 115773km2
Botswana 600372km2
Burkina faso 274200km2
Burundi 28490km2
Cameroon 475900km2
Cape verde 7275km2
Central africa republic 622984km2
Chad 1284000km2
Comoros 2117km2
congo 34965km2
cόte d’ ivoire 322463km2
djibouti 23310km2
DR congo 2345409km2
Egypt 1101449km2
Equatorial guinea 28051km2
Eritrea 124320km2
Ethiopia 1221900km2
Gabon 267667km2
Gambia 11369km2
Ghana 238537km2
Guinea 245957km2
Guinea bisau 36125km2
Kenya 582648km2
Lesotho 30460km2
Liberia 111369km2
Libya 1775000km2
Madagascar 592900km2
Malawi 118484km2
Mali 1240192km2
Mauritania 1030700km2
Mauritius 2040km2
Morocco 724730km2
Mozambique 802000km2
Niger 1267000km2
Namibia 824295km2
Nigeria 923773km2
Rwanda 26338km2
Sόo Tome & principe 964km2
Senegal 196192km2
Seychelles 453km2
Sierra leone 72325km2
Somalia 626541km2
South africa 221037km2
South sudan 644329km2
Sudan 1886068km2
Swaziland 17368km2
Tanzania 947419km2
Togo 56785km2
Tunisia 164154km2
Uganda 236036km2
Western sahara 252120km2
Zambia 752618km2
Zimbabwe 390759km2
The largest country in africa is Algeria while the smallest is Sychelle.
Offshore island also form part of africa;
- Seychelle
- Sao Tome and principe
- Mauritius
- Comoros
- Madagascar
- Cape verde
Activity
Draw and label map of africa(including all countries)
Major Latitudes and Longitudes
Major longitude is called prime meridian also called greenwich meridian
In africa it passes through:
- Ghana(Accra)
- Algeria
- Burkina faso
- Mali
All other longitudes are measured and named from prime meridian upto 180° on both sides
Major latitude in are three passing through africa
-
Equator 0°
- divides africa into two parts
- It passes through;
- Gabon
- Congo
- DR congo
- Uganda
- Kenya
- Somalia
-
Tropic of cancer 23½° north of equator
It passes through;- Western sahara
- Mali
- Mauritania
- Algeria
- Libya
- Egypt
-
Tropic of capricorn 23½° south of equator
It passes through:- Namibia
- Botswana
- South africa
- Mozambique
- Madagascar
Other important lines of latitude are far from africa are:
- Arctic circle 66½° N
- Antarctic circle 66½° S
Rotation of the Earth
This is movement of earth on its own axis. One complete rotation is 360°
The direction of the rotation is from west to east i.e.anticlockwise direction. One complete rotation takes 24 hours
Effects of Rotation of the Earth
- Differences in time along different longitudes
- Occurrence of day and night
Effects on time note:
24hrs=360
1hr= ?
(360 × 1) ÷ 24 =15
Therefore 1hr=15 or 360 = (24×60)minutes=1440min
1 = 1440 ÷ (360 ×1)= 4min
Example 1
The time in accra 0° is 7.00am.calculate time in bermbera 45°E
1hr =15
? = 45 = (45×1) ÷ 15 =3hrs
So 3hrs is equavalent to 45 then add 3hrs to 7.00am to get 10.00am
Revolution of the Earth
It is the movement of the earth around the sun on its own axis through a path known as orbit
Effects of the Revolution of the Earth
- Causes different seasons
- Summer
- Winter
- Spring
- Autumn
The four seasons follows
Summer → Autumn → Winter → Spring (SAWS)
- Differences in length of day and night
- In December North pole experiences longer hours of darkness than days
- In June south pole experiences longer hours of darkness than day
- In March and September days and night are equal. This is because neither south pole or north pole is facing the sun or away from it.
- Position of the midday sun
- On 21st June the sun is overhead at the tropic of cancer. This is called summer solstice
- On December 22nd the sun is overhead at the tropic of capricon. This is called winter solstice.
- On March 21st and September 23rd the sun is overhead at the equator. This is called Equinox.
Map Reading and Interpretation
A map is a representation of the earth or part of it on a flat surface.
The symbols used in a map help to identify;
- Economic activities
- Population distribution
- Relief
- Drainage of an area
Economic activities
These are things that people engage in to obtain wealthe.g –mining,fishing, farming, livestock keeping,trading,
| Quarry | People keep cattle or livestock |
| Road | People and goods are transported using road |
| Fish trap | People practise fishing |
| National Park | Tourism activities are carried out |
Relief
This is physical appreance of the earth’s surface. They include;
- Hills
- Valleys
- Plateaus
- Mountains
- Plains
High ground or plateaus may be identified by the presence of;
- Mountain
- River source
- Tea
- Coffee
- Pyrethrum
Low attitude or plains may be identified by presence of;
- Swamps
- Direction of flow of rivers
- Cotton
On the atlas colour:
- Light green represent plains
- Yellow represents plateaus
- Brown represents highlands
- Purple represents mountain tops
Drainage
Includes all water features. They are;
- Rivers
- Lakes
- Swamps
- Ponds
- Wells
- Human made lakes
Colour is used to represent drainage
- Seasonal rivers – broken blue lines
- Permanent rivers – continuous blue lines
Swampy areas have few settlement because they are breeding ground for mosquitoes
Population distribution and settlement
Many dots in an area indicate there are many people living there. Such areas are said to be densely populated.
When dots are far apart or scattered the area is said to be sparsely populated.
Physical Features
Main Physical Features of Africa
The main physical features in africa are:
- Plateaus
- Basins
- Valley
- Swamps
- Lakes
- Rivers
- Mountains and highlands
Activity
Our lives today pg 17
Draw map of africa showing main physical features
Plateaus
It is a high area which is generally level or flat ot the top
They are made up of very old and hard rocks
| Plateaus surface | Country where found |
| Fouta Djallon | Guinea |
| Bie plateau | Angola |
| Nyika plateau | East Africa |
| Jos plateau | Nigeria |
Basins
These are broad and shallow depressions. Most prominent ones are:
- Congo
- El Djouf
- Sudan
- Chad
- Kalahari
- Danakil depression
Other smaller basins – qattara in egypt,Lake victoria – kyoga basin
The lowest depression in africa is danakil depression
Valleys
It is a long depression on the earth surface
The world’s biggest and most famous is the great rift valley. It covers a distance of 5600km.
Great rift valley is divided into four sections
- Ethiopia rift valley
- Eastern branch
- Western branch
- Malawi rift valley
Ethiopian rift valley
- It begins from the red sea and extends down to lake turkana
Eastern branch
- Begins from lake turkana through kenya down to tanzania
Western branch
- Starts from lake rukwa in tanzania and runs along the borders of uganda and DRC to south sudan border.lake tanganyika, kivu,goerge,albert and edward are found in this branch.
Malawi rift valley
- It is a continuation of the eastern branch. Starts from lake malawi and ends at port of beira in mozambique
River shire valley, luangwa of zambia and the urema trough of mozambique are found here
Mountains and Highlands
The main highlands in africa include:
- Ethiopian highlands
- Guinea highlands
- Adamawa highlands in cameroon.
| Mountain | Country where found |
| Kilimanjaro | Tanzania |
| Kenya | Kenya |
| Elgon | Kenya/Uganda |
| Cameroon | Cameroon |
| Gimbala | Sudan |
| Ras dashan | Ethiopia |
| Margherita | Uganda/Congo |
| Toubkal | Morocco |
| Mountain Range | Country where found |
| Atlas | Morocco |
| Drankensberg | South Africa, Lesotho, Swaziland |
| Usambara | Tanzania |
| Cape Ranges | South Africa |
| Ruwenzori | Uganda |
| Ahaggar | Algeria |
| Tibesti | Chad |
| Aberdare | Kenya |
Lakes
Natural lakes
Lake victoria, tanganyika, malawi, chad, bangweulu.
- Victoria is the second largest lake in the world
- Tanganyika is the deepest (second)lake in the world
Human made lakes
Volta – ghana, kainji – nigeria, nasser – egypt, kariba on border of zambia and zimbabwe.
Some lakes are salty e.g. magadi, natron, shala, bogoria, nakuru.
Salty lakes have no river flowing out of them.
Rivers
Major rivers include the:nile, congo, niger, zambezi, benue, orange, limpopo, volta, senegal,
River Nile is the longest in africa
Rivers that form delta are; Niger, and Nile
Niger delta is the largest in africa
Other rivers drain into the sea or lake in a single channel called estuary.
Examples: are zambezi, congo and senegal.
Swamps
They are areas of soft,wet land covered with vegetation.
They are named according to the types of vegetation in them e.g.papyrus swamps have papyrus reeds
Mangrove swamps have mangrove trees.
Examples of swamps are;
- Okavango and makarikari in botswana
- Sudd along the nile in south sudan
- Lorian in kenya
- Lake – kyoga in uganda
- Malagasi in tanzania
- Swamp around lake chad
Formation of Mountains
There are four types of mountains
- Block mountain
- Volcanic mountain
- Fold mountains
- Residual mountains
Fold mountains
Formed after sedimentary rock fold at the edges
Examples of fold mountains includes:
- atlas in north africa
- Cape ranges in south africa
- Drankenberg in south africa
Residual mountains
Formed when rock masses are reduced in size after many years of erosion
Examples are namuli – mozambique, homboli – mali
Other smaller features which may be formed in smaller manner are inselbergs
Formation of Lakes
A lake is hollow or depression on the surface of the earth which is filled with water. Lakes are formed in different ways
- Erosion
- Earth movements
- Deposition
- Volcanic actions
- Human activities
Erosion
May be either through action of wind or glaciers
Wind actions
Examples are maghra, birket(lake siwa)both in egypt
Glacier actions
A glacier is a big block of moving ice
It is found on top of high mountains
Glacial lakes are known as tarns or corrie lake. Examples are teleki, hanging, gallary
Materials eroded by ice(moraine)may be deposited to form a barrier in a valley.
Behind such a barrier water may be collected to form a moraine dammbed lake.
Earth movements
They are of two types.these are;faulting and downwarping
- Faulting
Examples are:- Lake tanganyika – tanzania
- Eyasi – tanzania
- Malawi – malawi
- Edwajrd and george – uganda
- Turkana, baringo and magadi – kenya
- Downwarping
Examples of downwarping lakes are:- Victoria
- Kyoga
- Bangweulu
- Chad
Deposition
The lakes formed in this manner are ox-bow lakes
Examples are:
- Utange – on river rufiji in tanzania
- Kanyaboli – on river yala in kenya
- Gambi – on river tana in kenya.
Such lakes can also form in a delta areas e.g. lake manzala on nile delta.
Activity
draw diagrams on our lives today pg 24.
Volcanic activity
- Crater lakes
Examples of crater lakes are:- Lake shala – ethiopia
- Lake nyos – cameroon
- Lake paradise – kenya
- Lava – dammed lakes
Formed when water accumulates behind the lava barrier to form a lake
Examples:
- Lake kivu – uganda
- Lake tana – etiopia
- Lake itasy – madagascar
- Lake bunyoyi – uganda
Human activities
Lakes formed as a result of human activities are called artificial lakes
Examples:
- Lake nasser
- Lake kariba
- Lake volta
Relief Regions of Africa
Relief regions in africa are
- Plateaus
- Rift valley
- Highlands and mountains
- Coastal and lowlands
Plateaus
Is high and generally level ground
They lie between 400 – 2600 m above sea level
They have residuals hills (inselbergs)and valleys\
They are separated by short steep slopes known as scarps or escarpments.
The rift valley
The great rift valley enters africa from the red sea to beira in mozambique.
The narrowest part is about 30km wide while the widest is about 100km.
There are depressions occupied by lakes; e.g. bogoria and malawi etc
There are hills and mountains e.g. mt.longonot, suswa and ruwenzori
Some rivers flow along the floor of the rift valley .e.g. kerio, ewaso nyiro, and semliki
Highlands and mountains
Areas lying above 2000m can be described as highlands
Areas lying aove 2600m form mountains
The main highlands and mountains in africa
- Atlas mountains – morocco
- Ethiopia highlands – ethiopia
- East african highlands
- Ahaggar and tibesti mountains – chad
- Adamawa highlands – cameroon.
- Drankens berg and cape ranges – south africa
- Guinea highland – guinea
Mt.kilimanjaro is the highest in africa 5895m
Mt kenya – 5199m
Mt ruwenzori – 5109m
Coastal plains and lowlands
These are low – lying areas that border coast
They lie 0 – 400m above sea level.
They are narrow
Many parts are covered by sandy beaches
Climate
Climate is the average weather conditions of a particular place over a long period of time normally 30-35years
Factors Affecting Climate
- Relief and altitude
- Wind
- Latitudes
- Ocean currents
- Shape of the coastline
- Distance from the sea
Relief and Altitude
It influences the temperatures, the higher you go the cooler it becomes. The rate for every 100m of vertical height is 0.6
It also affects rainfall
Winds
Onshore wind absorbs water vapour from the sea and therefore bring rain to the land.
Offshore wind are dry winds and bring no rainfall.
The wind which influenceclimate in africa are;
- Westerly winds – bring rainfall to mediterranean
- North-east trade winds – they are offshore wind since they originate from asia.
- South-easttrade winds – they bring alot of rainfall to eastern africa
- South-westerly winds – they bring alot of rain to west africa and congo basin.
- Hamarttan winds – they are hot and dry. They cause dry conditions to the north and west africa.
Activity
Draw map of africa showing the winds.our lives today bk 7 pg 29
Latitude
This is the distance from equator.
Places near the equator experiences high temperatures while those far awy expriences lower temperatures
Africa lies within the tropics that is 23½° N and 23½° S. This region does not experience big change in
temperature during the different seasons.
Places outside the tropics experience winter and summer seasons. This is because the farther away one moves
from the tropics the cooler it gets.
Ocean Currents
These are the horizontal movements of water in the ocean.
They can be either be cold or warm.
Cold moves toward the equator while warm away from the equator.
The cold ocean currents are;
- Canary current
- Benguela current
Cold current cause fog and mist to land
Warm currents are;
- Somali current
- Mozambique current
- Guinea current
Warm currents causes rainfall to the land
Distance from the sea
Places that are far away from the sea receive low rainfall than those that are near.
This rainfall is called convectional rainfall
The sea also helps in the formation of cool sea breezes and land breezes
Shape of the coast line
When winds blow parallel to the coastline, they bring no rainfall to the land e.g. coast of ghana
Example axim town receives more rainfall than accra.
Climatic Regions of Africa
Africa has the following climatic regions
- Equatorial
- Tropical/savannah
- Mediterranean
- Mountain
- Desert and semi desert
- Humid sbtropical
- Warm continental
Characteristics of climatic regions of africa
Equatorial Climate
Also called hot and wet climate It is experienced in;
- Nigeria
- Liberia
- Cote d ivoire
- Sierra leone
- Gabon
- Cameroon
- Congo
- Democratic repblic of congo
Characteristics
- Receives heavy rainfall – highest rainfall between April to June and lowest rainfall between september to october
- Have double maxima rainfall
- Most of the rainfall is convectional
- Rainfall is accompanied by thunder and lightning
- Temperatures are high throughout the year
- No dry season
- Dinurnal temperature range is small
- High humidity
Savannah Climate
Also called tropical climate.
Mainly found within the tropics
Characteristics
- Experiences hot rainy season and acool dry season
- Temperature range is between 15 C to 25 C.
- When the rainy season is being experienced in the north of the equator, the dry season inthe south of africa and vice versa
- Rainfall ranges from 380mm to 2000mm p.a.
Mediterranean Climate
It is experienced to the north africa along coast of;morocco, algeria, tunisia and around benghazi in libya.
Also experienced in south africa around cape town.
Characteristics
- Experience hot, dry summer and cool, wet winter
- During the winter season, winds are on shore hence rain , while during summer winds are offshore hence no rain.
- Annual rainfall varies from 500 – 750mm
- Most rainfall is brought by westerly winds
- Temperatures range between 13 C and 24 C.
Semi – desert Climate
Experienced in kalahari and the sahal regions
This region have low rainfall and high temperatures
Characteristics
- Rainfall between 380-500mm p.a.
- Temperature between 22 C to 27 C
- The skies are generally clear
Desert or Arid Climate
True desert are experienced in sahara in north africca and in the namib in namibia
Characteristics
- Lands are dry
- Highest temperatures 58°C and lowest 4°C
- The skies are normally cloudless
- Diurnal
- Temperature range is very big.
- Rainfall is less than 250mm p.a. it fall within short period accompanied by storms.
Humid Subtropical Climate
Experienced in the coastal areas of eastern cape province and natal in south africa and also in mozambique.
Is influenced by warm mozambique currents and south east trade wind.
Characteristics
- Rainfall between 900 to 11500mm
- Most rainfall falls in summer.
- Both convectional and relief rainfall are recieved.
- Temperature range betwwen 13°C to 26°C.
Warm Continental Climate
Also known as the high veld climate
Experienced between the mediterranean climate zone of cape region in south africa and the humid subtropical
zone.
Characteristics
- Rainfall received all year
- Annual rainfall between 780mm in the east and 400mm in the west
- Winds from the indian ocean influence the rainfall.
- Temperature from 10°C to 19°C.
Mountain Climate
Also known as alpine climate
It is influenced by altitude
Characteristics
- Temperature decreases with increase in altitude
- High rainfall is received in mountain areas due to rising of moist air.
- Seasons exprienced in africa
Activity draw the diagrams on our lives today bk 7 pg 37
Places outside the equatorial regions but within the tropics, we have tropical region.these regions experience dry seasons and rainy seasons during other parts of the year.
Places farther away from equatorial and tropical regions experiences the four seasons
Mediterranean lands experiences hot and dry summer and cool, wet winter
Arid and semi-arid regions experiences hot and dry seasons throughout the year.
Influences of Climate on Human Activities
- Savannah are used for grazing
- Wild animals in savannah encourage tourism
- In the hunid subtropical region of south africa sheep are reared for meat and wool.
- Sawmilling is common in equaltorial regions
- Nomadic pastralism is practised in desert and semi desert regions
- Farming is practised in equatorial, modified equatorial, tropical and subtropical climatic zone.
- Tourism is practised at the top of mt.kenya, kilimanjaro and ruwenzori mountain because of snow.
- Climate influences types of houses to be built e.g.in wet areas the roof is steep for water to drain while flat tops are built in hot areas e.g. manyatta among the maasai.
- Areas that encourages breeding of mosquitoes and tsetse discourage settlement e.g.miombo woodland in tanzania and lambwe valley in kenya
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