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Urban heat islands affect human

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health and it affects energy consumption. Those two things alone are

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enough to drive worldwide interest. (Zhang) When we

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build an urban area, we're replacing the vegetated surface and also

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the soil surface with this imperious surface like the

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paving material and the building material. By doing this, we're basically

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warming the urban areas, and this will generate a temperature difference.

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And that's what we can the urban heat island. We find out

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that the urban heat island affected by several factors.

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The first factor will be the surrounding ecological context.

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And then will be the size of the city. When talking about size, we can

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we mean both the area of the city and also the population size

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of the city. And then will be the shape of the city

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and also the development patterns of the city.

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(Imhoff) We used a variety of satellite data, both land surface data

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from MODIS and also impervious surface data from the

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Landsat satellite. Inpervious surface data essentially tells us

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how much building material is on the land surface in order to study the urban

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heat island. The urban heat island is much larger if you

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convert a forested area into an urban. And this is because the urban

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heat island is a relative measure. So, urban areas in forests

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are much warmer than the surrounding landscape than they are in deserts

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for example, because the surrounding landscape is already warm.

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I think the general public should be interested in urban heat islands because of the

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fact that it's where most of the people live and in the next

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50 years, we're going to see 80% of the global population living in

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cities. And the urban heat island matters for

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everything from health, like asthma and heart conditions,

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to how much heating and air conditioning you need to use to