Urban Climate

Question 1

Albedo

Answer 1

The reflectivity of a surface.

The ratio between the amount of incoming insolation & the amount of energy reflected back into the atmosphere.
Light surfaces reflect more than dark surfaces & so have a greater albedo.

In simple terms, it is the amount of solar radiation (insolation) that is reflected by the Earth`s surface and the atmosphere.

Question 2

Anticyclonic

Answer 2

High atmosphere pressure = fine weather. Dry, calm conditions. In summer, can lead to heat wave conditions. In winter, will be cold, clear with blue skies

Question 3

Channelling

Answer 3

Wind redirected down long, straight canyon-like streets where there is less friction. These are sometimes referred to as urban canyons.

Question 4

Hygroscopic (nuclei)

Answer 4

Water-attracting e.g. dust in the atmosphere around which raindrops can form = hygroscopic nuclei.

Question 5

Insolation

Answer 5

Incoming solar radiation.

Question 6

Isotherm

Answer 6

A line joining places with equal temperature (like contours joining places of equal height).

Question 7

Microclimate

Answer 7

The small-scale variations in temperature, precipitation humidity, wind speed and evaporation than occur in a particular environment such as an urban area

Question 8

Particulates

Answer 8

Microscopic matter referred to as PM10 (from exhausts, cement dust, tobacco smoke and ash) and PM2.4.(fine particulate matter)

Question 9

Photochemical pollution

Answer 9

A form of air pollution that occurs mainly in cities and can be dangerous to health.

Exhaust fumes become trapped by temperature inversions and, in the presence of sunlight, low-level ozone forms. It is associated with high- pressure weather systems.

Question 10

Temperature inversion

Answer 10

An atmospheric condition in which temperature, unusually, increases with height.
As inversions are extremely stable conditions and do not allow convection, they trap pollution in the lower layer of the atmosphere.

Question 11

Urban climate

Answer 11

A set of climatic conditions that prevail in a large metropolitan area, which differ from the climate of the rural surroundings.

Question 12

Urban Dome

Answer 12

This is the area within which the weather is different from that of surrounding rural areas.

The urban microclimate is sometimes called an Urban Dome.

There are 2 levels in the dome: the Urban Canopy & the Urban Boundary layer.

Question 13

Urban heat island (UHI)
Urban heat island effect (UHIE)

Answer 13

The zone around and above an urban area, which has higher temperatures than the surrounding rural areas.