1. How does human activity affect climate?
Urban Climates
How does human activity affect climate?

2. The Effects of the Urban Climate in the U.K.
WHY?

3. Urban Heat Island Where highest? London night – May Where lowest?
Range?
London night – May
Why best at night?
In high pressure?
Draw a cross-section

4. Urban heat Island cross-section – USA City

5. Albedos Nearer to 1 = more energy reflected Car engines / exhausts
Impact of parks?
when greatest?
Buildings with central heating

6. Urban Rainfall Sun’s energy absorbed by buildings
Decreased air pressure
Increased air pressure
Cumulus cloud where rising warm air meets colder air
Convectional rain
More dust particles for condensation nuclei

7. Urban Winds Wind is funnelled by tall buildings Prevailing wind
Gusty winds may be two or three times stronger than average
‘canyon’ effect of tall buildings

8. Future Trends – different cities
What are the advantages and disadvantages of the urban microclimate for a city dweller?
What trends can we see for ‘all’ cities?