Heat Budget

View mindmap
  • Heat Budget
    • energy is from the sun in the form of shortwave solar radiation also known as insolation
    • 50% of insolation is absorbed by the surface of the Earth and then released as longwave radiation. i.e. infrared.
      • this radiation heats up the traposphere
      • OTHER 50% of incoming solar radiation is split into three ways
        • 20% absorbed by air and clouds
        • 25% reflected back into space by air and clouds
        • 5% reflected back into space by earths surface
      • Horizontal Heat transfer
        • 80% of heat transferred away from tropics is carried by the winds in the jet stream, hurricanes and depressions
          • rest is transferred by movement of warmer ocean currents towards the poles
      • Vertical Heat transfer
        • radiation transferred by radiation conduction and convection. Latent heat also helps
          • E.G. additional energy is required to change ocean into vapour which rises condenses as water droplets e.g.cloud.
            • precipitation will release energy and warm the upper atmosphere. this vertical motion transfers heat from areas of positive hear budget by cooling as it rises to help transfer warm air to poles
    • Factors Affecting Amount of Solar Radiation recived
      • Solar Constant
        • the amount of solar radiation from sun
        • varies slightly with suns activity when sun is more active earth receives more solar radiation
      • Earths distance from Sun
        • as sun changes its orbit
        • when earth is closer to sun receives more solar radiation
      • Height of Sun
        • varies with latitude
        • near the Equator the sun is higher in the sky and incoming radiation is spread over smaller surface area
        • Near the poles the sun is lower in the sky and incoming solar radiation is spread over a larger surface area
          • =less solar radiation per m2 at higher latitudes
      • Length of Day and Night (Diurnal)
        • varies with seasons
        • winter there are fewer hours of daylight - less solar radiation
      • proportion of land and sea
        • land and sea react differently to insolation.
          • Land heats up quicker than the sea(water has greater specific heat capacity) but oceans retain heat for longer
      • Aspect
        • slopes alter the angel at which the sun strikes the earth
          • South facing slopes in N hemisphere receive more of the available insolation than S facing
      • Urbanisation
        • Urban surfaces tend to absorb more heath than natural surfaces during day and radiate more at night =urban heat island


No comments have yet been made

Similar Geography resources:

See all Geography resources »See all Weather systems resources »