pg.+461

**__#20)__**

a) The albedo of a city is higher than that of a forest because of the following: First of all, in cities, you find materials like concrete, asphalt, and roof shingles that absorb radiation. Also, the colours of these materials are normally dark shaded colours, making them absorb heat, rather than reflecting it. Not only do these substances absorb radiation, but the tall buildings in cities block the infrared radiation, keeping it from escaping. On the other hand, forest areas include much lighter coloured surfaces that reflect radiation. Therefore, these rural areas have a lower albedo than that of cities.

b) White rock.

c) I would choose white rock because of its colour - white. White reflects heat/radiation rather than absorbing it.

d) Tar

e) Tar would take the longest because first of all, it is dark coloured which means that it absorbs heat and radiation for a long period of time. Secondly, the thickness of the substance makes it harder for it to cool down quickly.

f) Conduction is the transfer of heat from one substance to another, meaning that in an urban heat island, the rays from the sun hit different materials that absorb the heat and then transfer it to the materials around it. The transfer of heat creates the urban heat island.

g) In an urban heat island, convection would help because it would transfer the heat within liquids. For example, in lakes the heat would be transferred as well as the solar radiation in a city.