Urban microclimate, wind and precipitation

Urban areas have a lower albedo than surrounding rural areas

• True

• False

What percentage more cloud is there in an urban area than a rural area?

• 1-5%

• 5-10%

• 10-15%

• 15-20%

Select the correct causes of increased precipitation in urban areas

• Greater density of condensation nuclei

• Updraughts caused by unstable air

• Greater rates of evapotranspiration from vegetation

• Convection caused by urban heating

The zone around and above an urban area which has higher temperatures than the surrounding rural areas is known as the

How much more precipitation do urban areas receive than surrounding rural areas?

• 2-3%

• 5-15%%

• 15-20%

• 20-30%%

Which of these is the correct definition for the Venturi effect?

• Wind directed down long straight canyon-like streets where there is less friction

• The squeezing of wind into an increasingly narrow gap resulting in a pressure decrease and velocity increase

• Urban and suburban areas experience higher temperatures than the surrounding rural areas and this is the difference between them

• The reflectivity of a surface - the ration between incoming insolation and the amount of energy reflected back into the atmosphere

What is this a definition of 'an atmospheric condition in which temperature, unusually, increases with height.'

Give the key term for this definition: 'This the heat released by human

activity. Metabolic heat (body heat)is negligible, but the heat released from vehicles, central heating (alternatively, in some warmer areas, from air conditioning systems) and industrial activities is substantial.'

Is the sky-view factor increased or decreased by tall buildings in cities?

• increased

• decreased

Insolation can warm surfaces – the

degree of warming depends on the

amount of insolation absorbed by the

surface. This in turn depends on how

much is reflected off that surface.

This reflectance is the ______