Urban heat island - Revision history

Editor at 17:28, 15 September 2020

2020-09-15T17:28:58Z

← Older revision		Revision as of 17:28, 15 September 2020
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	* Thermal comfort.		* Thermal comfort.
	* Thermal optical properties.		* Thermal optical properties.
−	* Types of cool ~~roof~~.	+	* Types of cool roofs.

	=== External references ===		=== External references ===

Editor at 17:27, 15 September 2020

2020-09-15T17:27:56Z

← Older revision		Revision as of 17:27, 15 September 2020
Line 36:		Line 36:
	* Thermal comfort.		* Thermal comfort.
	* Thermal optical properties.		* Thermal optical properties.
		+	* Types of cool roof.

	=== External references ===		=== External references ===
Line 53:		Line 54:
	* Wolf, D. and J. T. Lundholm (2008). "Water uptake in green roof microcosms: Effects of plant species and water availability." Ecological Engineering 33(2): 179-186.		* Wolf, D. and J. T. Lundholm (2008). "Water uptake in green roof microcosms: Effects of plant species and water availability." Ecological Engineering 33(2): 179-186.

−	[[Category:~~Theory~~]] [[Category:~~Standards_/_measurements~~]] [[Category:~~DCN_Standard~~]] [[Category:Sustainability]]	+	[[Category:DCN_Definition]] [[Category:DCN_Guidance]] [[Category:DCN_Research,_Development_and_Innovation]] [[Category:Theory]] [[Category:Standards_/_measurements]] [[Category:Sustainability]]

Designing Buildings at 14:18, 2 March 2020

2020-03-02T14:18:18Z

← Older revision		Revision as of 14:18, 2 March 2020
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	See also: Cool roofs.		See also: Cool roofs.

−	NB The SuDS Manual (C753), published by CIRIA in 2015 refers to the reduction of ~~th eurban heast~~ island effect as 'urban cooling'.	+	NB The SuDS Manual (C753), published by CIRIA in 2015 refers to the reduction of the urban heat island effect as 'urban cooling'.

	-----		-----
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	* Wolf, D. and J. T. Lundholm (2008). "Water uptake in green roof microcosms: Effects of plant species and water availability." Ecological Engineering 33(2): 179-186.		* Wolf, D. and J. T. Lundholm (2008). "Water uptake in green roof microcosms: Effects of plant species and water availability." Ecological Engineering 33(2): 179-186.

−	[[Category:Theory]] [[Category:Standards_/_measurements]] [[Category:Sustainability]]	+	[[Category:Theory]] [[Category:Standards_/_measurements]] [[Category:DCN_Standard]] [[Category:Sustainability]]

Designing Buildings at 14:17, 2 March 2020

2020-03-02T14:17:46Z

← Older revision		Revision as of 14:17, 2 March 2020
Line 14:		Line 14:

	See also: Cool roofs.		See also: Cool roofs.
		+
		+	NB The SuDS Manual (C753), published by CIRIA in 2015 refers to the reduction of th eurban heast island effect as 'urban cooling'.

	-----		-----
−	This article was created by --[[User:Buro_Happold\|Buro Happold]].	+	This article was originally created by --[[User:Buro_Happold\|Buro Happold]].

	= Related articles on Designing Buildings Wiki =		= Related articles on Designing Buildings Wiki =

131.111.185.40 at 19:34, 25 September 2019

2019-09-25T19:34:16Z

← Older revision		Revision as of 19:34, 25 September 2019
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	* Synnefa, A., M. Santamouris, et al. (2007). "Estimating the effect of using cool coatings on energy loads and thermal comfort in residential buildings in various climatic conditions." Energy and Buildings 39(11): 1167-1174.		* Synnefa, A., M. Santamouris, et al. (2007). "Estimating the effect of using cool coatings on energy loads and thermal comfort in residential buildings in various climatic conditions." Energy and Buildings 39(11): 1167-1174.
	* Takakura, T., S. Kitade, et al. (2000). "Cooling effect of greenery cover over a building." Energy and Buildings 31(1): 1-6.		* Takakura, T., S. Kitade, et al. (2000). "Cooling effect of greenery cover over a building." Energy and Buildings 31(1): 1-6.
		+	* [https://doi.org/10.1016/j.buildenv.2019.01.006 Simulation pathway for estimating heat island influence on urban/suburban building space-conditioning loads and response to facade material changes.] Gunawardena et al., 2019.
	* Wolf, D. and J. T. Lundholm (2008). "Water uptake in green roof microcosms: Effects of plant species and water availability." Ecological Engineering 33(2): 179-186.		* Wolf, D. and J. T. Lundholm (2008). "Water uptake in green roof microcosms: Effects of plant species and water availability." Ecological Engineering 33(2): 179-186.

	[[Category:Theory]] [[Category:Standards_/_measurements]] [[Category:Sustainability]]		[[Category:Theory]] [[Category:Standards_/_measurements]] [[Category:Sustainability]]

131.111.185.40 at 19:25, 25 September 2019

2019-09-25T19:25:24Z

← Older revision		Revision as of 19:25, 25 September 2019
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	* CIBSE (2007). Green roofs. Plymouth.		* CIBSE (2007). Green roofs. Plymouth.
	* Erlandsson, M. and M. Borg (2003). Generic LCA-methodology applicable for buildings, constructions and operation services--today practice and development needs. 38: 919-938.		* Erlandsson, M. and M. Borg (2003). Generic LCA-methodology applicable for buildings, constructions and operation services--today practice and development needs. 38: 919-938.
		+	* [https://doi.org/10.1016/j.scitotenv.2017.01.158 Utilising green and bluespace to mitigate urban heat island intensity], Gunawardena et al., 2017.
	* Getter, K. L., D. B. Rowe, et al. (2007). "Quantifying the effect of slope on extensive green roof stormwater retention." Ecological Engineering 31(4): 225-231.		* Getter, K. L., D. B. Rowe, et al. (2007). "Quantifying the effect of slope on extensive green roof stormwater retention." Ecological Engineering 31(4): 225-231.
	* Roberts, S. (2008). "Effects of climate change on the built environment." Energy Policy.		* Roberts, S. (2008). "Effects of climate change on the built environment." Energy Policy.

Editor at 14:31, 9 November 2018

2018-11-09T14:31:17Z

← Older revision		Revision as of 14:31, 9 November 2018
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	This has a significant impact on thermal comfort in city environments. During a summer heatwave in the UK employers lost an estimated £168 million per day in productivity in one week (Roberts 2008).		This has a significant impact on thermal comfort in city environments. During a summer heatwave in the UK employers lost an estimated £168 million per day in productivity in one week (Roberts 2008).

−	In addition to this, heat islands are an energy efficiency concern due to increased air conditioning requirements which raise energy consumption, peak electricity demand and energy prices (Synnefa, Santamouris et al. 2007). Typically electricity use in cities increases 2-4% for every temperature increase of one degree Celsius (Akbari, Pomerantz et al. 2001) . These costs are likely to increase further if global temperatures rise and increasing urbanisation makes the Urban Heat Island effect more significant.	+	In addition to this, heat islands are an energy efficiency concern due to increased air conditioning requirements which raise energy consumption, peak electricity demand and energy prices (Synnefa, Santamouris et al. 2007). Typically, electricity use in cities increases 2-4% for every temperature increase of one degree Celsius (Akbari, Pomerantz et al. 2001) . These costs are likely to increase further if global temperatures rise and increasing urbanisation makes the Urban Heat Island effect more significant.

	Hotter urban environments will lead to an increase in the use of air conditioning. It follows that there will be a further increase in city temperatures from the dumping of heat from buildings heating ventilation and air conditioning (HVAC) systems and so more air cooling will be required (Takakura, Kitade et al. 2000). In other words, this process could be described as a vicious circle or negative reinforcing loop. There will also be an impact from increased emissions from cooling if this cooling is provided by fossil fuel based electricity. This will lead to an increased rate of global warming.		Hotter urban environments will lead to an increase in the use of air conditioning. It follows that there will be a further increase in city temperatures from the dumping of heat from buildings heating ventilation and air conditioning (HVAC) systems and so more air cooling will be required (Takakura, Kitade et al. 2000). In other words, this process could be described as a vicious circle or negative reinforcing loop. There will also be an impact from increased emissions from cooling if this cooling is provided by fossil fuel based electricity. This will lead to an increased rate of global warming.
Line 18:		Line 18:
	This article was created by --[[User:Buro_Happold\|Buro Happold]].		This article was created by --[[User:Buro_Happold\|Buro Happold]].

−	~~= Find out more =~~	+	= Related articles on Designing Buildings Wiki =
−		+
−	=== Related articles on Designing Buildings Wiki ===	+

	* Albedo.		* Albedo.
Line 26:		Line 24:
	* Emissivity.		* Emissivity.
	* Green roofs.		* Green roofs.
		+	* Green space.
	* Overheating.		* Overheating.
	* Preventing overheating.		* Preventing overheating.

Editor at 15:51, 22 November 2017

2017-11-22T15:51:11Z

← Older revision		Revision as of 15:51, 22 November 2017
Line 3:		Line 3:
	The Urban Heat Island effect is primarily caused by the replacement of natural surfaces with hard impervious surfaces that are generally dark and absorb large amounts of solar radiation. Urban hard surfaces are significant in the built environment in the form of roads, paved areas, and roof tops (Getter, Rowe et al. 2007).		The Urban Heat Island effect is primarily caused by the replacement of natural surfaces with hard impervious surfaces that are generally dark and absorb large amounts of solar radiation. Urban hard surfaces are significant in the built environment in the form of roads, paved areas, and roof tops (Getter, Rowe et al. 2007).

−	It is estimated that pavements and roofs account for 60% of urban surfaces, roofs 20-25% and pavements approximately 40% (Akbari, Menon et al. 2009). Presently these surfaces have relatively low albedo values (the fraction of incoming radiation reflected by a body) and high thermal conductivities, typically absorbing and re-radiating around 90% of the total incident solar radiation (Wolf and Lundholm 2008). This contributes to an Urban Heat Island effect that can result in a rise in summer temperatures of 4-~~7oC~~ (CIBSE 2007; Wolf and Lundholm 2008) in comparison with adjacent vegetated areas.	+	It is estimated that pavements and roofs account for 60% of urban surfaces, roofs 20-25% and pavements approximately 40% (Akbari, Menon et al. 2009). Presently these surfaces have relatively low albedo values (the fraction of incoming radiation reflected by a body) and high thermal conductivities, typically absorbing and re-radiating around 90% of the total incident solar radiation (Wolf and Lundholm 2008). This contributes to an Urban Heat Island effect that can result in a rise in summer temperatures of 4-7°C (CIBSE 2007; Wolf and Lundholm 2008) in comparison with adjacent vegetated areas.

	This has a significant impact on thermal comfort in city environments. During a summer heatwave in the UK employers lost an estimated £168 million per day in productivity in one week (Roberts 2008).		This has a significant impact on thermal comfort in city environments. During a summer heatwave in the UK employers lost an estimated £168 million per day in productivity in one week (Roberts 2008).
Line 9:		Line 9:
	In addition to this, heat islands are an energy efficiency concern due to increased air conditioning requirements which raise energy consumption, peak electricity demand and energy prices (Synnefa, Santamouris et al. 2007). Typically electricity use in cities increases 2-4% for every temperature increase of one degree Celsius (Akbari, Pomerantz et al. 2001) . These costs are likely to increase further if global temperatures rise and increasing urbanisation makes the Urban Heat Island effect more significant.		In addition to this, heat islands are an energy efficiency concern due to increased air conditioning requirements which raise energy consumption, peak electricity demand and energy prices (Synnefa, Santamouris et al. 2007). Typically electricity use in cities increases 2-4% for every temperature increase of one degree Celsius (Akbari, Pomerantz et al. 2001) . These costs are likely to increase further if global temperatures rise and increasing urbanisation makes the Urban Heat Island effect more significant.

−	Hotter urban environments will lead to an increase in the use of air conditioning. It follows that there will be a further increase in city temperatures from the dumping of heat from buildings heating ventilation and air conditioning (HVAC) systems and so more air cooling will be required (Takakura, Kitade et al. 2000). In other words this process could be described as a vicious circle or negative reinforcing loop. There will also be an impact from increased emissions from cooling if this cooling is provided by fossil fuel based electricity. This will lead to an increased rate of global warming.	+	Hotter urban environments will lead to an increase in the use of air conditioning. It follows that there will be a further increase in city temperatures from the dumping of heat from buildings heating ventilation and air conditioning (HVAC) systems and so more air cooling will be required (Takakura, Kitade et al. 2000). In other words, this process could be described as a vicious circle or negative reinforcing loop. There will also be an impact from increased emissions from cooling if this cooling is provided by fossil fuel based electricity. This will lead to an increased rate of global warming.

	Successfully modelling the Urban Heat Island effect is an ongoing process. In the UK this research is looking at the effect in London and is been investigated by University College London (UCL). Their work under the [http://www.homepages.ucl.ac.uk/~ucftiha/index.html LUCID] project is looking at how to develop a Local Urban Climate Model and apply it to the Intelligent Design of Cities.		Successfully modelling the Urban Heat Island effect is an ongoing process. In the UK this research is looking at the effect in London and is been investigated by University College London (UCL). Their work under the [http://www.homepages.ucl.ac.uk/~ucftiha/index.html LUCID] project is looking at how to develop a Local Urban Climate Model and apply it to the Intelligent Design of Cities.
Line 30:		Line 30:
	* Solar reflectance index.		* Solar reflectance index.
	* Smart cities.		* Smart cities.
		+	* Solar shading.
	* Sustainability.		* Sustainability.
	* The benefits of urban trees.		* The benefits of urban trees.

Editor at 10:09, 4 July 2016

2016-07-04T10:09:54Z

← Older revision		Revision as of 10:09, 4 July 2016
Line 27:		Line 27:
	* Green roofs.		* Green roofs.
	* Overheating.		* Overheating.
		+	* Preventing overheating.
	* Solar reflectance index.		* Solar reflectance index.
	* Smart cities.		* Smart cities.

Designing Buildings at 11:28, 16 May 2016

2016-05-16T11:28:26Z

← Older revision		Revision as of 11:28, 16 May 2016
Line 1:		Line 1:
−
	The Urban Heat Island (UHI) effect is the term given to localised higher temperatures that are experienced in urban environments compared with the temperatures of surrounding green spaces (Akbari and Konopacki 2005).		The Urban Heat Island (UHI) effect is the term given to localised higher temperatures that are experienced in urban environments compared with the temperatures of surrounding green spaces (Akbari and Konopacki 2005).

	The Urban Heat Island effect is primarily caused by the replacement of natural surfaces with hard impervious surfaces that are generally dark and absorb large amounts of solar radiation. Urban hard surfaces are significant in the built environment in the form of roads, paved areas, and roof tops (Getter, Rowe et al. 2007).		The Urban Heat Island effect is primarily caused by the replacement of natural surfaces with hard impervious surfaces that are generally dark and absorb large amounts of solar radiation. Urban hard surfaces are significant in the built environment in the form of roads, paved areas, and roof tops (Getter, Rowe et al. 2007).

−	It is estimated that pavements and roofs account for 60% of urban surfaces, roofs 20-25% and pavements approximately 40% (Akbari, Menon et al. 2009). Presently these surfaces have relatively low albedo values (the fraction of incoming radiation reflected by a body) and high thermal conductivities, typically absorbing and re-radiating around 90% of the total incident solar radiation (Wolf and Lundholm 2008). This contributes to an Urban Heat Island effect that can result in a rise in summer temperatures of 4-~~7<sup>o</sup>C~~ (CIBSE 2007; Wolf and Lundholm 2008) in comparison with adjacent vegetated areas.	+	It is estimated that pavements and roofs account for 60% of urban surfaces, roofs 20-25% and pavements approximately 40% (Akbari, Menon et al. 2009). Presently these surfaces have relatively low albedo values (the fraction of incoming radiation reflected by a body) and high thermal conductivities, typically absorbing and re-radiating around 90% of the total incident solar radiation (Wolf and Lundholm 2008). This contributes to an Urban Heat Island effect that can result in a rise in summer temperatures of 4-7oC (CIBSE 2007; Wolf and Lundholm 2008) in comparison with adjacent vegetated areas.

	This has a significant impact on thermal comfort in city environments. During a summer heatwave in the UK employers lost an estimated £168 million per day in productivity in one week (Roberts 2008).		This has a significant impact on thermal comfort in city environments. During a summer heatwave in the UK employers lost an estimated £168 million per day in productivity in one week (Roberts 2008).
Line 16:		Line 15:
	See also: Cool roofs.		See also: Cool roofs.

−	----	+	-----
		+	This article was created by --[[User:Buro_Happold\|Buro Happold]].

−	~~This article was created by --[[User%3ABuro%20Happold\|Buro Happold]].~~	+	= Find out more =
−		+
−	= ~~'''~~Find out more~~'''~~ =	+

	=== Related articles on Designing Buildings Wiki ===		=== Related articles on Designing Buildings Wiki ===
−	*Albedo.	+
−	*Cool roofs.	+	* Albedo.
−	*Emissivity.	+	* Cool roofs.
−	*Green roofs.	+	* Emissivity.
−	*Overheating.	+	* Green roofs.
−	*Solar reflectance index.	+	* Overheating.
−	*Smart cities.	+	* Solar reflectance index.
−	*Sustainability.	+	* Smart cities.
−	*Thermal comfort.	+	* Sustainability.
−	*Thermal optical properties.	+	* The benefits of urban trees.
		+	* Thermal comfort.
		+	* Thermal optical properties.

	=== External references ===		=== External references ===
−	*The [http://www.homepages.ucl.ac.uk/~ucftiha/index.html LUCID] project.
−	*Akbari, H. and S. Konopacki (2005). "Calculating energy-saving potentials of heat-island reduction strategies." Energy Policy 33(6): 721-756.
−	*Akbari, H., S. Menon, et al. (2009). "Global cooling: increasing world-wide urban albedos to offset CO2." Climatic Change 94(3): 275-286.
−	*Akbari, H., M. Pomerantz, et al. (2001). "Cool surfaces and shade trees to reduce energy use and improve air quality in urban areas." Solar Energy 70(3): 295-310.
−	*CIBSE (2007). Green roofs. Plymouth.
−	*Erlandsson, M. and M. Borg (2003). Generic LCA-methodology applicable for buildings, constructions and operation services--today practice and development needs. 38: 919-938.
−	*Getter, K. L., D. B. Rowe, et al. (2007). "Quantifying the effect of slope on extensive green roof stormwater retention." Ecological Engineering 31(4): 225-231.
−	*Roberts, S. (2008). "Effects of climate change on the built environment." Energy Policy.
−	*Synnefa, A., M. Santamouris, et al. (2007). "Estimating the effect of using cool coatings on energy loads and thermal comfort in residential buildings in various climatic conditions." Energy and Buildings 39(11): 1167-1174.
−	*Takakura, T., S. Kitade, et al. (2000). "Cooling effect of greenery cover over a building." Energy and Buildings 31(1): 1-6.
−	*Wolf, D. and J. T. Lundholm (2008). "Water uptake in green roof microcosms: Effects of plant species and water availability." Ecological Engineering 33(2): 179-186.

−	[[Category:Theory]]	+	* The [http://www.homepages.ucl.ac.uk/~ucftiha/index.html LUCID] project.
−	[[Category:Standards_/_measurements]]	+	* Akbari, H. and S. Konopacki (2005). "Calculating energy-saving potentials of heat-island reduction strategies." Energy Policy 33(6): 721-756.
−	[[Category:Sustainability]]	+	* Akbari, H., S. Menon, et al. (2009). "Global cooling: increasing world-wide urban albedos to offset CO2." Climatic Change 94(3): 275-286.
		+	* Akbari, H., M. Pomerantz, et al. (2001). "Cool surfaces and shade trees to reduce energy use and improve air quality in urban areas." Solar Energy 70(3): 295-310.
		+	* CIBSE (2007). Green roofs. Plymouth.
		+	* Erlandsson, M. and M. Borg (2003). Generic LCA-methodology applicable for buildings, constructions and operation services--today practice and development needs. 38: 919-938.
		+	* Getter, K. L., D. B. Rowe, et al. (2007). "Quantifying the effect of slope on extensive green roof stormwater retention." Ecological Engineering 31(4): 225-231.
		+	* Roberts, S. (2008). "Effects of climate change on the built environment." Energy Policy.
		+	* Synnefa, A., M. Santamouris, et al. (2007). "Estimating the effect of using cool coatings on energy loads and thermal comfort in residential buildings in various climatic conditions." Energy and Buildings 39(11): 1167-1174.
		+	* Takakura, T., S. Kitade, et al. (2000). "Cooling effect of greenery cover over a building." Energy and Buildings 31(1): 1-6.
		+	* Wolf, D. and J. T. Lundholm (2008). "Water uptake in green roof microcosms: Effects of plant species and water availability." Ecological Engineering 33(2): 179-186.
		+
		+	[[Category:Theory]] [[Category:Standards_/_measurements]] [[Category:Sustainability]]