Climate

• Climate vs. Weather:

  • Climate refers to the sum total of weather conditions and variations over a large area for a long period of time (more than thirty years)
  • Weather refers to the state of the atmosphere over an area at any point of time
• Elements of weather and climate:

  • Temperature, atmospheric pressure, wind, humidity, and precipitation
• Climate of India:

  • Described as the 'monsoon' type
  • Found mainly in the south and southeast of Asia
  • Perceptible regional variations in climatic conditions within the country
• Six major controls of climate:

  • Latitude
  • Altitude
  • Pressure and wind system
  • Distance from the sea (continentality)
  • Ocean currents
  • Relief features
• Latitude and solar energy:

  • Amount of solar energy received varies according to latitude
  • Air temperature generally decreases from the equator towards the poles
• Altitude and temperature:

  • As one goes from the surface of the earth to higher altitudes, the atmosphere becomes less dense and temperature decreases
  • Hills are cooler during summers
• Pressure and wind system:

  • Depend on the latitude and altitude of the place
  • Influence temperature and rainfall pattern
• Sea's moderating influence on climate:

  • As distance from the sea increases, moderating influence decreases
  • Experience extreme weather conditions known as continentality (very hot summers, very cold winters)
• Ocean currents and coastal climate:

  • Ocean currents along with onshore winds affect coastal areas
  • Warm or cold currents flowing past a coastal area will warm or cool it if winds are onshore
• Relief features and climate:

  • High mountains act as barriers for cold or hot winds
  • High mountains may cause precipitation if they lie in the path of rain-bearing winds
  • Leeward side of mountains remains relatively dry