Microclimates

Question 1

What is a microclimate?

Answer 1

The small scale variations in temperature, precipitation, humidity, wind speed and evaporation that occur in a particular environment.

Question 2

What is temperature inversion?

Answer 2

An atmospheric condition in which temperature increases with height
- not the norm

Question 3

What is the urban heat island effect?

Answer 3

The characteristics of urban areas and activity within them cause the areas to produce and retain more heat than the surrounding areas

Question 4

Reasons that urban heat islands develop (x5):

Answer 4

1. Wasted heat from urban activities
   - traffic, factories, homes (air conditioning, heating systems), higher concentration of people
2. Urban materials
   - building surfaces are darker so have a lower albedo so absorb and store more solar energy
   - tarmac, concrete, brick emit absorbed heat as long wave radiation = warms surroundings
3. Less vegetation
   - so less heat energy is lost via evapotranspiration
4. Urban drainage systems
   - reduce amount of surface water as rain is transported elsewhere via drains
   - so less energy lost in evaporation

Question 5

Reasons that temperatures can fluctuate in urban areas?

Answer 5

• seasons
• weather conditions
• size of the city
• ground cover
• sun intensity

Question 6

Name-drop example: Atlanta?

Answer 6

Urban sprawl - gets rid of green areas
Heat kills more people than any other event

Mitigation:
- tree canopy
- white roofs in new buildings
- green roofing

Question 7

Name-drop example: Phoenix?

Answer 7

Where the heat is felt the most correlated with where there’s the most child poverty
Poorer areas: no pavements, hardly any trees, more concrete, darker surfaces
Trees can lower temps by 8 degrees C
Reflective roofs can help