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• Absolute location


  The exact spot at which the place is found on the globe
• Determining absolute location


  Use imaginary lines around the earth
• Latitude


  Degrees north or south of the equator (0-90°)
• Longitude


  Degrees east or west of the Prime Meridian (0-180°)
• Equator


  Divides the earth into Northern and Southern hemispheres
• Prime Meridian

  Divides the earth into Eastern and Western hemispheres (Greenwich, England)
• Climatology is the science of climate which study the physical and spatial state of the atmospheric conditions averaged over a period of time
• Climatology


  From Greek κλίμα, klima, "place, zone"; and -λογία, -logia
• Branches of climatology


  • Physical and Dynamic climatology
  • Regional Climatology
  • Applied Climatology
• Climate


  The average range of weather experienced at a place or in a region over a long period of time
• Weather


  What you get
• Climate


  What you expect
• Climatology studies the physical state of the atmosphere over a specific region during a specific period on the basis of climatic data
• Geography studies the Earth as the habitat of Man


  It is closely related with climatology
• Physical Geography studies the spatial distribution of climatic conditions
• Understanding the climate and how it's changing (and the potential results of those changes) affect people now and can help plan for the future
• Atmosphere can be categorised based on

  • Composition
  • Temperature variation with height
  • Functions
• Composition of the atmosphere

  • Permanent Gases
  • Variable Gases
• Permanent gases in dry air

  • Nitrogen (78.08%)
  • Oxygen (20.95%)
  • Argon (0.93%)
  • Neon (0.0018%)
  • Helium (0.0005%)
  • Hydrogen (0.00006%)
  • Xenon (0.000009%)
• Variable gases in dry air

  • Water vapour (0 to 4%)
  • Carbon Dioxide (0.038%)
  • Methane (0.00017%)
  • Nitrous oxide (0.00003%)
  • Ozone (0.000004%)
  • Chlorofluorocarbons (CFCs) (0.00000002%)
• For CO2, 385 ppm means that out of every million air molecules, 385 are CO2 molecules
• Stratospheric ozone values at altitude between 11 km and 50 km are about 5 to 12 ppm
• Layers of the Earth's Atmosphere based on Atmospheric Composition


  • Homosphere
  • Heterosphere
• Layers of the Earth's Atmosphere based on Temperature variation with height

  • Troposphere
  • Stratosphere
  • Mesosphere
  • Thermosphere
  • Exosphere
• Troposphere


  Lowest and thinnest layer, 16 km at equator, 8 km at poles, 90% of the atmosphere's mass, temperature decreases with altitude, where weather occurs
• Tropopause

  Boundary between the troposphere and the stratosphere
• Stratosphere


  Extends from 10 km to 50 km above the ground, less dense (less water vapor), temperature increases with altitude, almost no weather occurrence, contains high level of ozone (ozone layer)
• Stratopause

  Upper boundary of the stratosphere
• Mesosphere

  Extends to almost 80 km high, gases are less dense, temperature decreases as altitude increases, gases in this layer absorb very little UV radiation
• Thermosphere


  Above the mesosphere and extends to almost 600 km high, temperature increases with altitude, readily absorbs solar radiation, temperature can go as high as 1,500 °C, reflects radio waves
• Exosphere


  The interface between Earth and space, atoms and molecules can escape to space
• Atmosphere can be categorised based on function

  • Ionosphere
  • Ozonosphere (ozone layer)
• Ozonosphere (ozone layer)


  The concentrated layer of ozone found in the stratosphere, ozone (O3) absorbs ultraviolet light between 0.1 - 0.3 micrometer (µm)
• Ionosphere


  Not really a layer of the atmosphere, but an electrified field of ions and free electrons, absorbs cosmic rays, gamma rays, X-rays, and shorter wavelengths of ultraviolet radiation, the spectacular display of aurora lights is generally found in this region
• Stratospheric ozone is good ozone, protects Earth from harmful UV radiation, depletion is detrimental to life
• Tropospheric ozone is bad ozone, in the troposphere ozone is a pollutant
• CFCs are pollutants
• Global Warming


  An increase in Earth's average surface temperature caused by an increase in greenhouse gases
• Greenhouse Effect


  The trapping of heat by gases in the atmosphere
• Greenhouse gases


  • Carbon dioxide
  • Sulfur dioxide
  • Ozone
  • CFCs
  • Water vapor