2. CONCEPT
Anabatic winds : Warm winds that blow up a valley slope
during the day.
Anticyclone (high pressure) Forms as a result of sinking air. Air
movement is anticlockwise, divergent (outwards), subsiding
(sinking) in the southern hemisphere, e.g. South Atlantic High,
South Indian High and Kalahari High.
Aspect : The direction in which a slope faces.
Berg winds : Hot, dry winds that blow from the interior of South
Africa to coastal areas.
Climate change : Long-term changes to the global climate,
resulting in unusual and extreme (stronger) weather conditions
3. 1 Synoptic
weather map
interpretation
On a synoptic weather map there are lines
called isobars:
• These lines join points of equal pressure (all
along one isobar the pressure is the same).
• The pressure is measured in hectopascals
(hpa)/millibars (mb).
• The isobars form patterns (shapes formed
by many isobars). Figures 1.1.1A and B show
a low pressure and a high pressure cell.
5. Factors affecting the
South African climate
There are three factors that have the greatest impact
on South Africa’s climate:
• South Africa is surrounded by oceans and ocean
currents.
• South Africa is mostly found on a plateau.
• South Africa is affected by the subtropical high
pressure belt
