Social Sciences Geography Term 2

• Climate


  The general conditions of the atmosphere a place can expect
• Weather


  The day-to-day conditions in the atmosphere
• Climate region


  A large area that has similar climate conditions
• Climate describes the general weather conditions that a place can expect. It is possible to divide the world into a number of climate regions. Each of the regions has a particular kind of climate.
• Descriptions about climate are made after looking at climate information over a long period, usually about 30 years. The two most important parts of climate are rainfall and temperature.
• Temperature

  How hot or cold a place gets, measured in degrees Celsius
• Rainfall


  How much rain falls over a particular time, measured in millimetres
• Climate graphs are a way of presenting climate information about temperature and rainfall. Climate data provides information about the average amount of rain that falls each month, as well as the average total rainfall for a year.
• Factors that influence temperature and rainfall

  • Distance from the equator (latitude)
  • Distance from the sea
  • Height above sea level
  • Ocean currents
  • Mountains (relief)
• Solar radiation

  Heat from the sun
• Latitude


  • Generally, temperature decreases with latitude. Places close to the equator have higher temperatures than places close to the poles.
• The shape of Earth and the tilt of its axis cause the poles to receive less solar radiation than the equator, resulting in lower temperatures at the poles.
• Distance from the sea

  Places far from the sea have hotter summers and cooler winters than places close to the sea. The sea helps to cool coastal places in summer and warm them in winter.
• Solids and liquids heat up and cool down differently. Solar radiation heats the land to a higher temperature than it heats water.
• Altitude

  Height above sea level
• The higher a place is, the lower the temperature. Temperature decreases with altitude at an average rate of 6.5°C for every 1000 metres of altitude.
• Air is thinner at higher altitudes, resulting in less efficient heat transfer and cooler temperatures.
• Ocean currents


  Large masses of water that constantly move in the top 100-200 metres of the world's oceans
• The main causes of ocean currents are winds, differences in water temperature, and the rotation of the Earth.
• Warm ocean currents

  Air over them is warmed, absorbing moisture and releasing it as rain. Places next to warm currents often have warm temperatures and high rainfall.
• Cold ocean currents


  Air over them is cooled, causing moisture loss as rain. Areas next to cold currents tend to have cool, dry climates.
• Relief


  The shape of the land
• Mountains can affect temperature by receiving more or less solar radiation, and can affect rainfall by forcing air to rise and release moisture or creating rain shadow areas.
• South Africa has diverse physical features including plateaus, mountains, escarpments, river valleys, and coastal plains.
• Factors influencing temperature and rainfall in South Africa

  • Distance from the equator (latitude)
  • Distance from the sea
  • Altitude
  • Ocean currents
  • Mountains (relief)
• A physical map focuses on physical features rather than human-made features such as roads and settlements
• Physical maps use colour to show the different height of the land, rivers and oceans
• Factors that influence temperature and rainfall in South Africa

  • Distance from the equator (latitude)
  • Distance from the sea
  • Altitude
  • Ocean currents
  • Mountains (relief)
• The temperature and rainfall of every place in South Africa is influenced by more than one of the five factors shown in Figure 2
• One factor usually has more influence than the other four
• Altitude


  Has the greatest influence on temperatures in Gauteng
• Johannesburg would have warmer temperatures and greater rainfall if it was at sea level next to the Indian Ocean
• The warm Agulhas ocean current has the greatest influence on Durban's climate
• The inland areas of KwaZulu-Natal are affected by the following factors: latitude, altitude, mountains, and distance from the sea
• The importance of each factor depends on the location of a particular place
• Extreme

  At the high or low end of a scale, far from the centre
• Average temperature (also referred to as mean temperature)

  Calculated by adding several amounts together, finding a total, and dividing the total by the number of amounts
• Temperature range


  The difference between high and low temperatures
• Maximum temperature

  The highest temperature recorded in a given time
• Minimum temperature

  The lowest temperature recorded in a given time