Explain what this picture shows. (your definition of heat island)

Explain what this picture shows. (your definition of heat island)

The term "heat island" refers to urban air and surface temperatures that are

higher than nearby rural areas.

Urban Climate Dome

Outline how these factors work to promote a heat island.

1. Concrete and man made surfaces

2. Less water in the soil and environment

3. Excess energy from buildings

Albedo

• IMPORTANT technical term– How much radiation a surface reflects– Lighter the surface the higher the albedo

Tar, asphalt, brick and concrete absorb insolation from the sun (in different amounts)and release it as heat, rather than reflecting it.

During the day in rural areas, the solar energy absorbed near the ground

evaporates water from the vegetation and soil. Thus, causes evaporative cooling.

In cities, where there is less vegetation, the buildings, streets and sidewalks absorb the

majority of solar energy input.

What about the buildings and the people in them?

We made list of the heat producing parts of a city.

The activities that humans take part in that would be more common in a city….

Cars/buses/air conditioning (we did more?)

Remember, the way the heat island effect works, is that it increases the overall

temperature of the city.

(a bit like the greenhouse effect)

But in particular, it raises night time temperatures (not always day time) by the

slow releasing of heat.

Which makes it an overall increase

Design an experiment so that we could measure if Douglas has a

heat island.

*Plan on paper, be ready to present. Individual work!

[Also, an experiment to see if the heat island is related to urbanisation.]

Create a glossary of important terms-Albedo / Particulates / Urban Heat Island

Cliff / Plateau / Sink / Anthropogenic Why does the Urban Heat Island occur?

When is it most noticeable? Using technical terms describe the pattern of

temperature variations and give possible reasons for such changes.