User talk:Hcps-levetab

Urban Heat Islands

What is an Urban Heat Island? They are areas that include more buildings and higher populations. This extra populations and buildings create an increased temperature when compared to the neighboring rural areas.

Different Categories of Urban Heat Islands The different stages of Urban Heat islands include the canopy layer, the boundary layer, surface layer. The canopy and the boundary layer heat islands refer to the warming of the atmosphere near and around the Urban area. The difference about these two are somewhat different. They are different because the canopy layer is the air that is the air effected nearest the city's streets and buildings. Also the canopy heat island air rise instead of falling like the boundary layer does. The boundary layer also lies above the canopy layer and may reach a thickness of 1 kilometer. Although the boundary level may reach 1 kilometer, it shrinks to hundreds of a meter. On the other the surface of the building and streets are somewhat hotter that the rural areas. These types of heat islands may vary due to the shape and the related time characteristics that contribute to the development of the Urban Heat Island. Finally the warmest air is found downtown with the greatest population of building and people.

Facts About Urban Heat Islands The reason why these hot spots are called heat islands are due to the fact of the isotherms forming a pattern that resembles a island. Normally there are steep rises in the areas right at the boundary near the rural areas. Also the solar heat effect the surface heat causing the already hot area even hotter. Another factor to causing urban heat islands are darker, dry surfaces because the absorb even more heat. CLHI's mean the heat island intensity rises from sunset to sundown where it is hotter near the sunset hours. CLHI's are normally weak or can even create a negative effect. SHI's are strong during the day and through the night.

Factors and Causes Some of these include weather, location,season, functions and for of the city. Also the wind and clouds effect the heat island because the block or trap the heat from reaching the city. Time and day effect the heat island because if it is winter then its cooler and if the sun is at mid day then it will be hotter. Alos building materials are atracted towards the heat. Finally the human reaction could cause a slight change in the heat around the city.A few causes are platlife that doesn't provide shade and dark surfaces such as streets and building that absorb a lot of heat.

Effects of Urban Heat Islands The mean air with about a million people is about 1-3 degrees celcius warmer than the surrounding rural areas. Also the may increase energy demand. These increased summertime heats bump air conditioning prices up and air quality to go down. Also green house gasses and air polutions goes up creating even more heat. Another way the heat island can be found as smog. Also the heat islands may effect your health to and extent.

World's biggest Urban Heat Island The country that contains the largest Urban Heat Island is the USA. It is in Washington D.C.

How to stop an Urban Heat Island There are ways to stop an Urban Heat Island. Like by using reflective roofs on buildings and by having more urban vegetation. Reflective Roofs on buildings reflect some of the sun's rays back and keep them from heating up the ground too much. Also, Urban vegetation, such as trees, providing shade and preventing some of the sun's rays from reaching the ground. This will also save money for the governments and people. Scientists estimate that by the year 2015 if we have the reflective roofing and the urban vegetation that the total amount of money saved in the USA will be around Four Billion Dollars. By: Allen Levet, Chris Marshall, and Vinh Dao

Sources: Rosenfeld, AR. (2000). Heat island group. 1(1), Retrieved from http://eetd.lbl.gov/HeatIsland/ EPA, EPA. (2010). Measuring heat islands. 1(1), Retrieved from http://www.epa.gov/hiri/about/index.htm

Voogt, JAV. (2004). Urban heat islands: hotter cities. 1(1), Retrieved from http://www.actionbioscience.org/environment/voogt.html

The University of Melbourne, UofM. (1994). Urban heat islands and climate change - melbourne, australia. 1(1), Retrieved from http://www.earthsci.unimelb.edu.au/~jon/WWW/uhi-melb.html

Oke, TRO. (2009). World meteorological organization. 1(1), Retrieved from http://www.wmo.int/pages/prog/www/IMOP/publications/IOM-81/IOM-81-UrbanMetObs.pdf

Are you aware...
...that we currently have an article on Urban heat island?

I don't know if your text here is for a class, or a draft for replacement of the article, or what. Syrthiss (talk) 14:23, 10 November 2010 (UTC)

This is for a class snce we couldn't create a normal page.