Examples

• Urban microclimate case study: London and Vancouver


  Urban microclimate case study: London and Vancouver
• What are the highest temperatures in London and where are they found?

  10-11°C found in the city centre
• What are the average temperatures on the rural-urban fringe?

  5°C
• Humidity in London vs surrounding areas

  Much lower in London due to the high temperatures the city experiences. The water is more easily evaporated which results in less humidity.
• Precipitation in London vs surrounding areas

  More precipitation in more hilly areas.

  Saturday rain is built of more pollutants due to the 5 day working week commute.
• Winds in London vs surrounding areas


  Absence of strong winds in London, cannot disperse hot air, or bring in cold air.

  Low pressure causes surface winds to be brought in from rural fringe.

  Urban boundary acts as orthographic uplift.
• What are the highest temperatures in Vancouver and where are they found?

  27°C found in CBD
• How much do temperatures decrease out of Vancouver centre by?

  From 20 to 15°C
• How much does the sea breeze in summer reduce temperatures by?

  5-10°C
• Humidity in Vancouver


  Lower in the day as less surface water is present.

  Rises over harbour.

  At night humidity tends to be higher due to dew deposits.
• Precipitation in Vancouver


  For every increase in 100m, rainfall increases by 100mm.

  Snow falls, however not near the warmer ocean and city centre as it melts.

  Relief is the most common cause of variation of rainfall.
• Wind in Vancouver


  Skyscrapers in CBD cause turbulence.

  Winds are weaker in CBD due to obstructing skyscrapers.

  Canyon streets can experience strong gusts when winds are funnelled between tall buildings.
• Urban microclimates: South Korea and Australia


  Urban microclimates: South Korea and Australia
• What were the changes in Cheong Gye Cheon, South Korea?

  Removal of large elevated motorway.

  Restoration of river and floodplain.

  Decrease in the amount of vehicles passing by.
• What were the impacts to these changes in Cheong Gye Cheon, South Korea?

  Since the river restoration, air temp has decreased by 10-13%, during the hottest days.

  Decrease in vehicles, decreased the temperature.

  River restoration has resulted in wind speed increasing by 2.2-7.1%.
• What were the changes in Melbourne, Australia?

  Green spaces have increased.

  Tree cover in suburbs decreases 2% every 10km from the city centre.

  5% fall in urban tree cover.

  Less trees due to property boom.
• What were the impacts of these changes in Melbourne, Australia?

  1-2°C rise in temperature- health concerns.

  Thinning of trees.

  Melbourne aims to increase to 75% before 2040.
• Components of the energy budgets that influence temperatures in hot deserts and equatorial regions

  Components of the energy budgets that influence temperatures in hot deserts and equatorial regions
• Incoming solar radiation in: equatorial regions vs hot deserts

  High (440 watts/m2 per year) vs Less (about 340 watts/m2 per year)
• Radiation at the earths surface in: equatorial regions vs hot deserts

  150-200 W/m2 vs 250-300 W/m2
• Absorption, scattering and radiation by cloud in: equatorial regions vs hot deserts

  Very high absorption and scattering.

  Outgoing radiation to space is very little.

  vs

  Low because it is cloudless, suns rays are high intensity.

  Outgoing long wave radiation from the warm surface is very large.
• Surface albedo: equatorial regions vs hot deserts

  Low vs high because soils are dry
• Energy absorbed onto the surface: equatorial regions vs hot deserts

  Wet soils conduct energy down vs little energy is transferred down into the rock or dry sand.
• Sensible heat transfer: equatorial regions vs hot deserts


  Strong uplift in daytime and early nighttime vs strong uplift by day and conduction cooling at night.
• Latent heat transfer: equatorial regions vs hot deserts

  Very high due to high air moisture.

  Vs

  Very low as the air is very dry.
• Radiation balance in: equatorial regions vs hot deserts

  Positive with larger surplus vs positive with smaller surplus