Grade 12
This is the original work of the Answer
Series Grade 12 Geography textbook
summarized only by school_notes.
It may not resell / distribute or
sold under a new license.
, Skool Instagram : @skool_notas
Email :
Notas
Website : https://skoolnotas.company.site/
Whatsapp : 081 369 9131
These notes may not be resold, copied, distributed or sold under a new license.
Climate and weather .........................................................................................................................................................2
Mid-Latitude cyclones ....................................................................................................................................................... 2
Tropical cyclones ................................................................................................................................................................... 7
Geomorphology .................................................................................................................................................................. 18
Drainage basins in South Africa .............................................................................................................................18
Fluvial processes ...................................................................................................................................................................21
Rural and Urban settlemant ..................................................................................................................................... 31
Study of settlements ..........................................................................................................................................................31
Classification of settlements according to size and complexity, pattern and
function .........................................................................................................................................................................................32
Rural settlements ..................................................................................................................................................................32
Rural settlement issues .................................................................................................................................................. 34
Urban settlements...............................................................................................................................................................37
Urban hierarchies............................................................................................................................................................... 38
Urban structure and patterns .................................................................................................................................39
Urban settlement issues ............................................................................................................................................... 44
Economic geography of South Africa ............................................................................................................. 47
The structure of the economy ................................................................................................................................. 47
Secondary and tertiary sectors ............................................................................................................................. 53
The informal sector ............................................................................................................................................................60
Geographical skills and techniques .................................................................................................................. 62
Mapwork skills .........................................................................................................................................................................62
Map scale ....................................................................................................................................................................................63
Orthophoto maps .............................................................................................................................................................. 65
Map Interpretation .............................................................................................................................................................66
Geographical Information System (GIS) ...........................................................................................................67
Map Projections ................................................................................................................................................................... 68
1
,Skool Instagram : @skool_notas
Email :
Notas
Website : https://skoolnotas.company.site/
Whatsapp : 081 369 9131
These notes may not be resold, copied, distributed or sold under a new license.
General characteristics
→ They move from west to east.
→ Air moves in a clockwise direction around the centre of a low pressure in the
Southern Hemisphere; but moves in an anticlockwise direction in the Northern
Hemisphere.
→ They often occur in "families" of 3 to 4 mid-latitude cyclones.
Areas of formation
→ Mid-latitude cyclones develop at the Polar front between 40º and 60º N and S.
→ The warmer westerly winds meet the cold polar easterly winds at the Polar front.
Conditions necessary for formation
→ At about 50º N and S, a transition zone called the Polar front, separates the
warm tropical air from the cold polar air.
→ This colder air pushes in underneath the warmer air while the warmer air gets
pushed up over the colder air.
→ A change in the conditions at the Polar front can be caused by the jet stream, a
mountain range or the shape of a coastline.
→ The isobars form in a circular pattern and a cell of low pressure begins to form.
Stages in the formation of a mid-latitude cyclone
Initial stage
→ The Polar front separates the cold Polar air from the south (polar easterlies) and
the warmer subtropical air from the middle latitudes (westerlies).
→ There is no movement across the line of separation between the two air masses.
→ The two air masses do not mix easily because of their different characteristics :
cold air is heavy and dense; warm air is light and less dense.
Development stage
→ A frictional drag occurs between the cold and the warm air masses, disturbing
the front.
→ The warm, less dense air is pushed up by the cold, dense air.
→ This results in a low pressure forming.
2
, Skool Instagram : @skool_notas
Email :
Notas
Website : https://skoolnotas.company.site/
Whatsapp : 081 369 9131
These notes may not be resold, copied, distributed or sold under a new license.
Mature stage
→ The air begins to rotate in a clockwise direction around
the low pressure (Southern Hemisphere).
→ The cold air pushes in under the warm air ahead of it and
uplift occurs.
→ A cold front leads the cold air.
→ The warm air rises up over the cooler air ahead of it and
uplift occurs.
→ A warm front leads the warm air of the warm sector.
Occluded stage
→ This stage is reached when all the warm air has been
lifted off the surface by the colder air.
→ The warm sector becomes narrower as the cold front
catches up with the warm front.
→ In time, the warm sector will be displaced above the cold
air.
Dissipating stage
→ This is the last stage of a mid-latitude cyclone - the system weakens.
Weather patterns associated with cold, warm and occluded fronts
Occluded weather conditions
→ An occlusion takes place when the cold front catches up with the warm front.
→ It closes the warm sector and isolates it from the earth's surface.
→ There are cold front occlusions and warm front occlusions.
3
This is the original work of the Answer
Series Grade 12 Geography textbook
summarized only by school_notes.
It may not resell / distribute or
sold under a new license.
, Skool Instagram : @skool_notas
Email :
Notas
Website : https://skoolnotas.company.site/
Whatsapp : 081 369 9131
These notes may not be resold, copied, distributed or sold under a new license.
Climate and weather .........................................................................................................................................................2
Mid-Latitude cyclones ....................................................................................................................................................... 2
Tropical cyclones ................................................................................................................................................................... 7
Geomorphology .................................................................................................................................................................. 18
Drainage basins in South Africa .............................................................................................................................18
Fluvial processes ...................................................................................................................................................................21
Rural and Urban settlemant ..................................................................................................................................... 31
Study of settlements ..........................................................................................................................................................31
Classification of settlements according to size and complexity, pattern and
function .........................................................................................................................................................................................32
Rural settlements ..................................................................................................................................................................32
Rural settlement issues .................................................................................................................................................. 34
Urban settlements...............................................................................................................................................................37
Urban hierarchies............................................................................................................................................................... 38
Urban structure and patterns .................................................................................................................................39
Urban settlement issues ............................................................................................................................................... 44
Economic geography of South Africa ............................................................................................................. 47
The structure of the economy ................................................................................................................................. 47
Secondary and tertiary sectors ............................................................................................................................. 53
The informal sector ............................................................................................................................................................60
Geographical skills and techniques .................................................................................................................. 62
Mapwork skills .........................................................................................................................................................................62
Map scale ....................................................................................................................................................................................63
Orthophoto maps .............................................................................................................................................................. 65
Map Interpretation .............................................................................................................................................................66
Geographical Information System (GIS) ...........................................................................................................67
Map Projections ................................................................................................................................................................... 68
1
,Skool Instagram : @skool_notas
Email :
Notas
Website : https://skoolnotas.company.site/
Whatsapp : 081 369 9131
These notes may not be resold, copied, distributed or sold under a new license.
General characteristics
→ They move from west to east.
→ Air moves in a clockwise direction around the centre of a low pressure in the
Southern Hemisphere; but moves in an anticlockwise direction in the Northern
Hemisphere.
→ They often occur in "families" of 3 to 4 mid-latitude cyclones.
Areas of formation
→ Mid-latitude cyclones develop at the Polar front between 40º and 60º N and S.
→ The warmer westerly winds meet the cold polar easterly winds at the Polar front.
Conditions necessary for formation
→ At about 50º N and S, a transition zone called the Polar front, separates the
warm tropical air from the cold polar air.
→ This colder air pushes in underneath the warmer air while the warmer air gets
pushed up over the colder air.
→ A change in the conditions at the Polar front can be caused by the jet stream, a
mountain range or the shape of a coastline.
→ The isobars form in a circular pattern and a cell of low pressure begins to form.
Stages in the formation of a mid-latitude cyclone
Initial stage
→ The Polar front separates the cold Polar air from the south (polar easterlies) and
the warmer subtropical air from the middle latitudes (westerlies).
→ There is no movement across the line of separation between the two air masses.
→ The two air masses do not mix easily because of their different characteristics :
cold air is heavy and dense; warm air is light and less dense.
Development stage
→ A frictional drag occurs between the cold and the warm air masses, disturbing
the front.
→ The warm, less dense air is pushed up by the cold, dense air.
→ This results in a low pressure forming.
2
, Skool Instagram : @skool_notas
Email :
Notas
Website : https://skoolnotas.company.site/
Whatsapp : 081 369 9131
These notes may not be resold, copied, distributed or sold under a new license.
Mature stage
→ The air begins to rotate in a clockwise direction around
the low pressure (Southern Hemisphere).
→ The cold air pushes in under the warm air ahead of it and
uplift occurs.
→ A cold front leads the cold air.
→ The warm air rises up over the cooler air ahead of it and
uplift occurs.
→ A warm front leads the warm air of the warm sector.
Occluded stage
→ This stage is reached when all the warm air has been
lifted off the surface by the colder air.
→ The warm sector becomes narrower as the cold front
catches up with the warm front.
→ In time, the warm sector will be displaced above the cold
air.
Dissipating stage
→ This is the last stage of a mid-latitude cyclone - the system weakens.
Weather patterns associated with cold, warm and occluded fronts
Occluded weather conditions
→ An occlusion takes place when the cold front catches up with the warm front.
→ It closes the warm sector and isolates it from the earth's surface.
→ There are cold front occlusions and warm front occlusions.
3
