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Temperature Variations
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| Insulation Warm colours, cool colours Land and sea | ||
| Energy... | As described on the previous page, temperatures and climates can vary considerably around the world. These differences are caused by a number of factors, such as how close the area is to oceans and mountains, as well as its height above sea level. The nature of the material involved and it's colour are also important - and these factors will be looked at in more detail below. There are more experiments for you to carry out in this section too! |
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Insulation |
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| Insulation... | Do you know what insulation is? An insulator is a material that prevents the flow of heat. (It is the opposite of a conductor – something like metal – which allows heat to pass through it very easily and quickly. That is why metal saucepan handles can get very hot when you are cooking). | |
| A good insulator is something that keeps warm things warm and cool things cool – the idea behind vacuum flasks. These flasks have an empty space (vacuum) between the inside and the outside walls that prevents heat from travelling from one side to the other. Air itself can also act as an insulator – and we can see this with a simple experiment. |
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| Experiment... | Take two
thermometers and wrap one in a towel. Put them both into a You should find that the thermometer that was wrapped in the towel
has a higher temperature than the other one. This is because the towel will have trapped a
layer of air around the thermometer. As air is a good insulator, the cold air from the
fridge could not pass through easily and the temperature therefore did not get as low. What |
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Warm colours, cool colours |
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| Colours... | Although it may sound surprising, even colours react differently to the sun’s rays. Let’s use our two thermometers again to test this out. | |
| Experiment... | Place one thermometer
under a white sheet of paper, and one |
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| When you have found the difference, you will see why houses in hot countries are often painted white. What colour clothes would you be cooler in on a hot summers day? |
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Land and sea, soil and water |
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| Soil and water... | It is not just different colours that are affected differently by heat. Different materials can also heat up and cool down at different rates – and two of the most obvious examples are soil and water. Shall we have a closer look? | |
| Experiment... | Place two thermometers in
containers of soil and water and leave Now move the containers into the shade. After an hour, have a look You should have noticed that the thermometer in the soil will first be warmer and then cooler than the one in the water. This is because soil warms up and cools down more quickly than water. |
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| Land and sea... | These differences can actually have important consequences on a larger scale. If we change the words soil and water to land and sea, we can use the experiment to explain one of the main regional climatic variations found around the world. |
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| Coasts... | Coastal areas often have a more constant climate and experience less dramatic temperature changes than neighbouring inland regions. This is because the sea is keeping the coastal area warm in winter and cool in summer. |
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| Now that we have learnt about sunshine, it is time to move on in our look at the features that power the weather. |
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fridge for 30 minutes, and when you take them out compare the two readings.
What is the difference in the two temperatures?
under a black or dark coloured sheet of
paper. After they have both been left in the sunshine for 30 minutes, what is the
difference between the temperatures on the two thermometers? 
both in the sun for an hour.
What is the difference in temperature after that time? 
at the two temperatures again.