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Mitigation of Urban heat islands[edit]

  • White roofs: Painting rooftops white has become a common strategy to reduce the heat island effect[1]. In cities, there are many dark colored surfaces that absorb the heat of the sun in turn lowering the albedo of the city[1]. White rooftops allows high solar reflectance and high solar emittance, increasing the albedo of the city or area the effect is occurring[1].
  • Green roofs: Green roofs are another method of mitigation of the urban heat island effect. Green roofery is the practice of having vegetation on a roof; such as having trees or a garden. The plants that are on the roof increase the albedo and decreases the urban heat island effect[1]. This method has been studied and criticized for the fact that green roofs are affected by climatic conditions of green roof variables are hard to measure, and are very complex systems [1]
  • Planting trees in Urban cities: Planting trees around the city can be another way of increasing albedo and decreasing the urban heat island effect. Trees absorb carbon dioxide and provide shade. It is recommended to plant deciduous trees because they can provide many benefits such as more shade in the summer and not blocking warmth of winter [2]

Mitigation policies, measures and other strategies[edit]

AB32 scoping plan[edit]

AB32 required the California Air Resources Board to create a scoping plan. This plan is California’s approach on how to carry out their goal of combatting climate change by reducing greenhouse emissions by 2020 to levels from the 1990’s. The scoping plan had four primary programs, advanced clean cars, cap and trade, renewables portfolio standard and low carbon fuel standard all geared toward increased energy efficiency. The plan has main strategies to reduce green house gases such as having monetary incentives, regulations and voluntary actions. Every five years the scoping plan is updated. [3]

  • The advanced clean car rules program was made to reduce tail pipe emissions. The Air Resources Board approved the program to control emissions for newer models from the year 2017 to 2025. Some of their goals by 2025 are to have more environmentally superior cars to be available in different models and different types of cars. New automobiles will emit 34 percent fewer global warming gases and 75 percent fewer smog-forming emissions. And if fully implemented consumers can save an average of $6,000 over the life of the car.[4]
  • The renewable portfolio standard mandates to increase renewable energy from a variety of sources such as solar power and wind. Investor-owned utilities, community choice aggregators and electric service providers are required to increase procurement to 33% by 2020.[5]
  • Low carbon fuel standards is administered by the California Air Resources Board and attempts to make wider choice of cleaner fuels to Californians. Producers of petroleum-based fuels are required to reduce the carbon intensity of their products to 10 percent in 2020.[6]
  • Cap and trade is designed to reduce the effects of climate change by setting a cap on greenhouse gases released into the atmosphere. The cap will decline approximately three percent each year in 2013. The trading will create incentives to reduce the effects of climate change in California communities by reducing greenhouse gases through investments in clean technologies.[7]

AB32 and urban heat islands[edit]

  • Urban heat islands increase demand for energy consumption during the summer when temperatures rise. As a result of increased energy consumption, there is an increase in air pollution and greenhouse gas emissions. This policy focuses on lowering greenhouse emmissions, which contributes to lowering the heat island effect.[8]

EPA Compendium of Strategies[edit]

This compendium focuses on a variety of issues dealing with urban heat islands. They describe how urban heat islands are created, who is affected, and how people can make a difference to reduce temperature. It also shows examples of policies and voluntary actions by state and local governments to reduce the effect of urban heat islands[9]


  • Sacramento Municipal Utility District (SMUD) and the Sacramento Tree Foundation have partnered to provide the city of Sacramento shade trees for free. The program allows citizens to receive trees from four to seven feet tall. They also give them fertilizer, and delivery, all at no cost.[10]They encourage citizens to plant their trees to benefit their home by reducing air conditioning costs. Approximately more than 450,000 shade trees have been planted in the Sacramento area.[11]
  • The Eco-Roof Incentive Program: In Canada, grants are distributed throughout Toronto for installing green and cool roofs on residential and commercial buildings. This will reduce usage of energy and lower green house gas emissions.[12]
  • Tree vitalize: This program is a partnership with multiple entities that focuses on helping restore tree cover in the city, it also educates citizens about the positive effects of trees on climate change and the urban heat island effect.[13] And another goal they have is to build capacity among local governments to understand, protect and restore their urban trees. Because there is a need for educating citizens about the maintenance of trees, Treevitalize provides nine hours of classroom and field training to community residents. The classes cover a variety of topics such as tree identification, pruning, tree biology, and proper species selection. [14]


U.S. Department of Energy Weatherization Assistance Program helps low income recipients by covering their heating bills and helping the families to make their homes energy efficient.[15] In addition, this program allows states to also use the funds to install cooling efficiency measures such as shading devices.[14]

Outreach and education[edit]

  • Tree Utah: a statewide non-profit organization is dedicated to educating communities about the environmental and social benefits provided by trees.[16]They are also committed to planting thousands of trees throughout the state of Utah.[17]

Tree Protection Ordinances[edit]

  • A variety of local governments have implemented tree and landscape ordinances, which will help communities by providing shade during summer. Tree protection is an ordinance that does not allow someone to prune or remove trees without a city permit. An example is the city of Glendale in California: Through the Indigenous Tree Ordinance, the city of Glendale protects the following species of trees, the California Sycamore, the Coast Live Oak,Mesa Oak, Valley Oak,Scrub Oak,California Bay. Anyone who is planning on removing or trimming the trees has to obtain an indigenous tree permit. Within the permit they have to provide detailed information about the number of trees affected, trunk diameter and the health of the tree itself. They also have to submit photographs of the site, and a site plan sketch.[19]
  • Another example is the city of Berkeley in California. The tree protection ordinance prohibits the removal of Coast Live Oak trees and any excessive pruning that can cause harm to the tree is also prohibited. The only exception is if the tree is poses a danger to life or limb and danger to the property.[20]

Co Benefits of mitigation strategies[edit]

Trees and gardens aid mental health[edit]

  • A large percentage of people who live in urban areas have access to parks and gardens in their areas, which are probably the only connections they have with nature. A study shows that having contact with nature helps promote our health and well-being. People who had access to gardens or parks were found to be healthier than those who did not.[22]
  • Another study done investigating whether or not the viewing of natural scenery may influence the recoveries of people from undergoing surgeries, found that people who had a window with a scenic view the had shorter post operative hospital stays and less negative comments from nurses.[23]

Tree planting as empowerment and community building[edit]

  • Los Angeles tree people, is an example of how tree planting can empower a community. Tree people provides the opportunity for people to come together, build capacity, community pride and the opportunity to collaborate and network with each other.[24]

Green roofs as food production[edit]

Green roofs and wild life biodiversity[edit]

  • Green roofs are important for wildlife because they allow organisms to inhabit the new garden. To maximize opportunities to attract wildlife to a green roof, one must aid the garden to be as diverse as possible in the plants that are added. By planting a wide array of plants, different kinds of invertebrate species will be able to colonize, they will be provided with foraging sources and habitat opportunities.[25]

Urban Forests and a cleaner atmosphere[edit]

  • Trees provide benefits such as absorbing carbon dioxide, and other pollutants.[26] Trees also provide shade and reduce ozone emissions from vehicles. By having many trees, we can cool the city heat by approximately 10 degrees to 20 degrees, which will help reducing ozone and helping communities that are mostly affected by the effects of climate change and urban heat islands.[27]


  1. ^ a b c d e Zinzi, M., and S. Agnoli. "Cool and green roofs. An energy and comfort comparison between passive cooling and mitigation urban heat island techniques for residential buildings in the Mediterranean region." Energy and Buildings. 55. (2012): 66-76. Print.
  2. ^ Rosenfield, Arthur, Joseph Romm, Hashem Akbari, and Alana Lloyd. "Painting the Town White -- and Green." MIT Technology Review. N.p., 14 07 1997. Web. 25 Feb 2014.
  3. ^ AB 32 Scoping Plan." Scoping Plan. N.p., n.d. Web. 06 Apr. 2014. <>.
  4. ^ "California's Advanced Clean Cars Program." Advanced Clean Cars. N.p., n.d. Web. 06 Apr. 2014. <>.
  5. ^ "California Renewables Portfolio Standard (RPS)." California Publics Utilities Commission. N.p., n.d. Web. 06 Apr. 2014. <>.
  6. ^ "Low Carbon Fuel Standard." Low Carbon Fuel Standard. N.p., n.d. Web. 06 Apr. 2014. <>.
  7. ^ "Cap-and-Trade Program." Air Resources Board. N.p., n.d. Web. 06 Apr. 2014. <>.
  8. ^ AB 32 Scoping Plan." Scoping Plan. N.p., n.d. Web. 06 Apr. 2014. <>.
  9. ^ "Reducing Urban Heat Islands: Compendium of Strategies | Heat Island Effect | US EPA." EPA. Environmental Protection Agency, n.d. Web. 06 Apr. 2014. <>.
  10. ^ "Reducing Urban Heat Islands: Compendium of Strategies | Heat Island Effect | US EPA." EPA. Environmental Protection Agency, n.d. Web. 06 Apr. 2014. <>.
  11. ^ "SMUD." SMUD Video Player. N.p., n.d. Web. 06 Apr. 2014. <>.
  12. ^ Ecoroof Incentive Program." Live Green Toronto, n.d. Web. <>.
  13. ^ "Reducing Urban Heat Islands: Compendium of Strategies | Heat Island Effect | US EPA." EPA. Environmental Protection Agency, n.d. Web. 06 Apr. 2014. <>.
  14. ^ a b "TreeVitalize." TreeVitalize. N.p., n.d. Web. 06 Apr. 2014.
  15. ^ "Reducing Urban Heat Islands: Compendium of Strategies | Heat Island Effect | US EPA." EPA. Environmental Protection Agency, n.d. Web. 06 Apr. 2014. <>.
  16. ^ "Reducing Urban Heat Islands: Compendium of Strategies | Heat Island Effect | US EPA." EPA. Environmental Protection Agency, n.d. Web. 06 Apr. 2014. <>.
  17. ^ "About." TreeUtah. N.p., n.d. Web. 06 Apr. 2014.
  18. ^ "Global Systems Science." Global Systems Science. N.p., 2012. Web. 06 Apr. 2014.
  19. ^ "Indigenous Tree Program." City of Glendale, CA :. N.p., n.d. Web. 06 Apr. 2014. <>.
  20. ^ "Tree Protection Program - City of Berkeley, CA." Planning and Development-City of Berkeley, CA. N.p., n.d. Web. 06 Apr. 2014. <>.
  21. ^ "City of Visalia - Street Tree Ordinance." Street Tree Ordinance. N.p., n.d. Web. 06 Apr. 2014. <>.
  22. ^ Maller, C. "Healthy Nature Healthy People: 'contact with Nature' as an Upstream Health Promotion Intervention for Populations." Health Promotion International 21.1 (2005): 45-54. Print.
  23. ^ Ulrich, R. "View through a Window May Influence Recovery from Surgery." Science 224.4647 (1984): 420-21. Print.
  24. ^ Wilmsen, Carl. Partnerships for Empowerment: Participatory Research for Community-based Natural Resource Management. London: Earthscan, 2008. Print.
  25. ^ a b Dunnett, Nigel. Small Green Roofs: Low-tech Options for Greener Living. Portland, Or.: Timber, 2011. Print.
  26. ^ Hilltop Arboretum. “Nature the Changing Climate and You: Act Locally!” 5.4 (2007). Web. <$Content/Newsletters/$file/07winter.pdf>
  27. ^ McPherson, Gregory, James Simpson, Paula Peper, Shelley Gardner, Kelaine Vargas, Scott Maco, and Qingfu Xiao. “Coastal Plain Community Tree Guide: Benefits, Costs, and Strategic Planting”. USDA, Forest Service, Pacific Southwest Research Station. (2006). Web.