Urban Environments

Green roofs: an analysis on air pollution removal and policy implementation

Evan 30 Comments

 

In October 1948, a thick cloud of air pollution formed above the industrial town of Donora, Pennsylvania. It lingered for five days, killed 20 people and induced sickness in 43% of the town (Environmental Protection Agency, 2007). Pollution poses a serious threat to our environment and health. Nearly one-quarter of the people in the U.S. live in areas with unhealthy short-term levels of particle pollution, and roughly one in ten people live where there are unhealthful levels year-round (American Lung Association, 2010). Air pollution is of particular concern to public health as it is the cause of hazards including upper respiratory irritation, chronic respiratory irritation, heart disease, lung cancer, and chronic bronchitis (Kampa & Castanas, 2008). The most common health-related impacts from air pollution are increased occurrences of respiratory illnesses such as asthma and a greater incidence of cardiovascular disease (Pope, Bates & Raizenne, 1995). Urban environments struggle heavily with air pollution due to the large amount of factories and vehicles that are major sources of air pollutants that accumulate so much that they become a hazard to human health. In Canada, the Ontario Medical Association found air pollution to result in 9,500 premature deaths per year (OMA, 2008) and estimates increased costs of healthcare up to $506.64 million and lost productivity of up to $374.18 as a result of air pollution (OMA, 2005). Conditions will only worsen as pollution grows with population, traffic, industrialization and energy use (Mayer, 1999). There are many pollutants in the air of an urban environment, though particulate matter (PM10), ozone (O?), sulfur dioxide (SO?), and nitrogen dioxide (NO?) are among the most serious to human health (World Health Organization, 2016).

Particulate matter that appears in urban environments is made up of sulfate, nitrates, ammonia, sodium chloride, black carbon, mineral dust and water that exist in the air from human activities such as combustion of fossil fuels, vehicles, and factory emissions. According to The World Health Organization (WHO), the limit for PM10 is 50 ?g/m3 annual mean. This represents how much particulate matter is allowed in the air annually by law. Chronic exposure to particles contributes to the risk of developing cardiovascular, respiratory diseases, and lung cancer (WHO, 2017).  In countries of Europe that have concentrations of PM above guideline levels, it is estimated that average life expectancy is 8.6 months lower than it would be if PM exposure from human sources was regulated (WHO, 2017).

NO2 is most commonly formed from anthropogenic burning of fuel (heating, power generation, and engines in vehicles/ships). The limit for nitrogen dioxide is 40 ?g/m3 annual mean. Epidemiological studies have shown that symptoms of bronchitis in asthmatic children increased in association with long-term exposure to NO2 and at short-term concentrations above 200 ?g/m3, NO2 is a toxic gas which causes significant inflammation of the airways (WHO, 2017). Reduced lung function growth is also linked to NO2 at higher concentrations currently measured in Europe and the US. The US EPA (1998) also focuses on the danger of NO2 by stating that Nitrogen oxides (NOx) resulting from combustion of fossil fuels can form ground level ozone that causes respiratory problems, premature deaths, and reductions in crop yields. (EPA, 1998).

Ozone at ground level, not to be confused with the ozone layer in the upper atmosphere, is formed from vehicle and factory emissions and emissions from solvents and industry. The legal amount that is allowed in cities is 100 ?g/m3 8-hour mean, which means that by law over 8 hours concentrations of ozone cannot exceed 100 ?g per cubic meter of air. In some cases, chemicals like nitrogen oxides (NOx) react with sunlight and also contribute to forms of ozone. The limit for ozone is 100 ?g/m3 8-hour mean and once this threshold is passed, O3 can cause breathing problems, trigger asthma, reduce lung function and cause lung diseases (WHO, 2017). The American Lung Association (2007) reported that annually, over 3,700 premature deaths in the United States (premature death is a death that occurs before a person reaches their expected age) can occur as a result of a 10 parts per billion (ppb) increase in O3 levels (ALA, 2007). Bell (2004) found that increased mortality rates in 95 urban areas within the US are linked to elevated levels in ozone, with one of these urban areas being Chicago, where ALA (2007) found over 2 million people at increased risk for health problems resulting from short-term exposure to O3 and particulate matters (ALA, 2007; Bell, 2004).

SO2 is a colourless gas with a sharp odour that is produced from the burning of sulfur-containing fossil fuels (coal/oil) for heating residences, generating power, and motor vehicles along with the smelting (extraction by melting) of mineral ores that contain sulfur. The limit for sulfur dioxide is 20 ?g/m3 24-hour mean and this means that air in cities will contain on average 20 ?g per cubic meter over the span of 24 hours. When the limit is exceeded, SO2 can affect the respiratory system, lung functioning, and cause irritated eyes. Evidence shows that the effects of sulfur dioxide are felt very quickly and most people would feel the worst symptoms of coughing, wheezing, shortness of breath, or a tight feeling around the chest in 10 or 15 minutes after breathing it in (S02, 2005). Inflammation of the respiratory tract causes coughing, mucus secretion, aggravation of asthma and chronic bronchitis and makes people more prone to infections of the respiratory tract (WHO, 2017).

One policy the U.S. government has in place to control pollution levels is the Clean Air Act (CAA) of 1970 (majorly revised in 1977 and 1990). The CAA’s purpose is to reduce air pollution and its harmful effects by setting limits on pollution. This Act requires states to meet specific air quality standards regarding six common pollutants: particulate matter, ozone, sulfur dioxide, nitrogen dioxide, carbon monoxide, and lead (EPA, 2017b). The Act contains specific provisions to address hazardous or toxic air pollutants, acid rain, chemical emissions that deplete the ozone layer, and regional haze (EPA, 2017b). The six “criteria” air pollutants are regulated based primarily on human health and secondarily on environmental criteria.

The CAA improved the environment which in turn improved the economy and human health. In the 45 years following the installation of the CAA, national emissions of the six common pollutants dropped an average of 70% while gross domestic product grew by 246% (EPA, 2017c). Forty-one areas that previously had unhealthy carbon monoxide levels in 1991 now meet the health-based national air quality standard. In 1990 alone, pollution reductions under the Act prevented 205,000 early deaths, 10.4 million lost I.Q. points in children due to lead exposure, and a multitude of other health effects (Environmental Protection Agency, 2017d). Despite massive improvements in air quality since CAA took effect, millions of Americans still live in areas with pollution levels exceeding the limits (EPA, 2007). Those who struggle to meet CAA air quality standards may find green roofs a useful tool to bring pollutant levels down.

In response to rising air pollutants, people are considering transforming city rooftops into green roofs to mitigate the problem. A green roof is a layer of vegetation installed on top of a roof, either flat or slightly sloped (National Park Service, 2017). The high amount of rooftop space in urban cities creates an opportunity for green roofs to be implemented on a large scale. Roofs represent 21–26% of urban areas and 40–50% of their impermeable areas (Wong, 2005; Dunnett & Kingsbury, 2004). These spaces typically have much unused surface area that could be repurposed to combat the aforementioned effects of harmful air pollutants, a green roof’s main purpose. The plants that compose the roof are able to take up compounds through their natural processes respiration and photosynthesis, which remove the pollutants from the air and improve its quality.WHO has guidelines for the limits of the primary air pollutants that must not be exceeded in urban environments. Green roofs will help keep the levels of PM10 at 50 ?g/m3 annual mean, nitrogen dioxide at 40 ?g/m3 annual mean, ozone at 100 ?g/m3 8-hour mean, and the concentrations of sulfur dioxide in the air of urban environments at 20 ?g/m3 24-hour mean.

Literature surrounding green roofs agrees on their impact of particulate matter removal (Speak, Rothwell, Lindley & Smith, 2012; Currie & Bass, 2008; Rowe, 2011; City of Los Angeles, 2005; Yang, Yu & Gong, 2008; Jayasooriya, Ng, Muthukumaran & Perera, 2017). The range of particulate that is annually reduced by a green roof is 0.42–3.21 g/m2 over 500,000 square meters of rooftops (Speak et al, 2012). Rowe (2011) performed a study where 2000 m2 of uncut grass were planted on a green roof. It was estimated that the green roof could remove up to 4000 kg of particulate matter. In a simulation where green roofs were built over 198,000 square meters of roofs in Chicago, 234.5 kg of particulate matter would be removed by green roofs in one year (Yang et al., 2008).  Yang et. al (2008) also did a study where the concentrations of acidic gaseous pollutants and particulate matters on a 4000 m2 roof in Singapore are measured before and after the installation of a green roof. Research found that the levels of particulate matter was reduced by 6% in the air above the roof after installation of the green roof (Yang et al., 2008). Jayasooriya et al. (2017) state that green roofs annually remove 1.53 g/m2 PM10  (Jayasooriya et al., 2017).Currie and Bass (2008) state that green roofs have the potential to reduce annual amounts of PM10 by .89–9.21 g/m2 (grams per square meter) over 486,000-2,430,000 square meters of green roof coverage in Toronto (Currie & Bass, 2008). Jayasooriya et al. (2017) states that green roofs annually remove 1.53 g/m2 PM10 (Jayasooriya et al., 2017). Another study on green roof remediation in Los Angeles (LA) puts these numbers of removed particulate matter into context. The city of LA found one square meter of green roof able to remove approximately 0.1 kg of particulate matter per year and if a gasoline powered vehicle were to release .01 grams of pm per mile of travel and drive 10,000 miles per year, then the vehicle would emit 100 grams per year (.01 kg/year) and therefore, one square foot of green roof would reduce the pollution of this theoretical car for the whole year (City of Los Angeles, 2005). According to the literature, the annual range of particulate matter reduced by green roofs fall between .42 g/m2 and 9.21 g/m2 (Speak et al., 2012; Currie & Bass, 2008; Rowe, 2011; City of Los Angeles, 2005; Yang et al., 2008; Jayasooriya et al., 2017).

Currie and Bass (2008) state that green roofs have the potential to reduce annual amounts of NO2 by 0.6–2.55 g/m2. Yang et. al (2008) found that if green roofs were built over 198,000 square meters of roofs in Chicago, 452.25 kg of nitrogen dioxide would be removed by green roofs in one year. Rosenfeld, Akbari, Romm, and Pomerantz (2008) calculated that emissions from coal fired power plants to the air could be reduced by 350 tons of NOx per day in Los Angeles by implementing green roofs. This value of energy saved from the installation of green roofs relates to a 10% reduction in the causes of smog to the city of Los Angeles, with an active NOx trade program, and results in a savings of one million dollars per day (Akbari, Pomerantz & Taha, 2001; Rosenfeld et al.,1998;  Clark, Talbot, Bulkley & Adriaens, 2005) estimate that if 20% of all industrial and commercial roof surfaces in Detroit, MI, were traditional extensive sedum green roofs, over 800,000 kg per year of NO2 , 0.5% of that area’s emissions, can be removed. Yang et. al (2008) states that green roofs annually remove 2.33–3.57 g/m2, NO2 in an urban environment. Jayasooriya et al. (2017) states that green roofs annually remove .37 g/m2 NO2. In a study done in Singapore, 21% of nitrous acid, a byproduct of nitrogen dioxide, was reduced directly above a green roof (Rowe, 2011). One study implementing green roofs in Kansas City, MO, used by the EPA, estimated that by 2020, green roofs would reduce 1800 pounds (816 kg) of NOx (EPA, 2016). After reviewing the literature, it is found that a green roof can reduce a range of 0.37-3.57 g/m2 (Currie & Bass, 2008; Yang et. al., 2008; Jayasooriya et al., 2017; Rosenfeld et al., 2008) Clark, Adriaens, and Talbot (2008) reported that green roofs yield an annual benefit of $0.45–$1.70 per m2 ($0.04–$0.16 per square foot) in terms of nitrogen oxide uptake. Clark et al. (2005) estimates that NOx reduction from a 2000 ft2 green roof would provide an annual benefit of $895–$3392, resulting in the green roof being 24.5-40.2% cheaper than a conventional roof without vegetation.

Currie and Bass (2008) state that green roofs have the potential to reduce annual amounts of O3 by 1.2–3.58 g/m2. Yang et al. (2008) state green roofs have the potential to annually reduce 4.49–7.17 g/m2 O3 and in their simulation of Chicago, green roofs were built over 198,000 square meters of roofs, the results were measured over the course of just one year, with 871 kg of O3 removed by green roofs. Jayasooriya et al. (2017) state that green roofs annually remove 1.24 g/m2 O3 . Since ozone is formed by the reaction of sunlight with pollutants such as nitrogen oxides (NOx), green house reduction in nitrogen oxides also reduce concentrations of ozone in the urban environment. According to the literature, the annual range of ozone reduced by green roofs fall between 1.2 g/m2 and and 7.17 g/m2 (Currie & Bass, 2008; Yang et. al., 2008; Jayasooriya et al., 2017).

Yang et. al (2008) found that if green roofs were built over 198,000 square meters of roofs in Chicago, 117.25 kg of sulfur dioxide would be removed by green roofs in one year. Currie and Bass (2008) state that green roofs have the potential to reduce annual amounts of SO2 by 0.2–0.84 g/m2. Yang et al. (2008) state that green roofs annually remove 0.65–1.01 g/m2 SO2. Jayasooriya et al. (2017) state that green roofs annually remove 0.1 g/m2 SO2. In a study done in Singapore, 37% of sulfur dioxide was reduced directly above a green roof (Rowe, 2011). One study implementing green roofs in Kansas City, MO, used by the EPA, estimated that by 2020, green roofs would reduce 2600 pounds (1179.34 kg ) of SO2 (EPA, 2016). In one field study, the concentrations of acidic gaseous pollutants and particulate matters on a 4000 m2 roof in Singapore are measured before and after the installation of a green roof. Research found that the levels of SO2 were reduced by 37% in the air above the roof after installation of the green roof (Yang et al., 2008). After reviewing the literature, it is found that a green roof can reduce a range of 0.10-1.01 g/m2 (Currie & Bass, 2008; Yang et al., 2008; Jayasooriya et al., 2017; Rowe, 2011, EPA, 2016)

As an example of the costs of building a green roof in a U.S. city, the installation costs to install green roofs on every roof in Chicago were estimated to be $35.2 billion (Yang et al., 2008). This brings up a high cost of green roofs that deters many cities from considering installation. The EPA projected in 2009 that extensive green roof installation costs, which were ranging from $15-$20/sq. foot should drop to $8-$15/sq. foot as installations increased, and soil substrate and plants became more available (EPA, 2009). Not everyone considers green roofs for their own homes, however, with the amount of pollution removed and human health improvements and the inherent existent pollution in cities, green roofs are critical to pollution removal in urban environments and should therefore be installed. In fact, having a green roof reduces more pollution in an urban environment than simply not having one at all. Agra, Klein, Vasl, Kadas, and Blaustein (2017) compared green roofs to other roofs of buildings with no vegetation at all (control roofs) and found that the control roofs had a CO2 concentration 50 cm above the ground of almost 375 ppm while the three types of green roofs in the study ranged from maintaining concentrations of 365-370 ppm of CO2 50 centimeters above surface (Figure 1). With green roofs being confirmed to be more effective With costs of green roofs accounted for and their associated improvement of human health via reduction in air pollution, green roofs can become even more desirable with the inclusion of governmental incentives/policies for cost reduction.

Seeing cost as one of the main obstacles standing in the way of green roofs, we urge government action to alleviate this issue. The U.S. government must make green roof installation less expensive through an incentive system. Funding should be granted to all major U.S. cities for the installation of green roofs. Depending on design, plant type, and climate conditions the price of green roof construction typically ranges from $15-20 per square foot, though the EPA projects that extensive green roof installation costs should drop to $8-$15/sq. foot as installations increase, and soil substrate and plants became more available (EPA, 2009). The U.S. Government should offer $10 per square foot of green roof for commercial, residential, and private properties. In target areas where pollution is most concentrated, the government should offer $15 per square foot. This proposal makes the initial up-front cost of green roofs more feasible, if not directly profitable.

Green roofs become more attainable and widespread with the help of government incentives, as shown by successful policies in Washington D.C. Currently, Washington D.C. has over 3 million square feet of green roof (Department of Energy & Environment, 2017a). The district set a goal that by 2020, 20% of its buildings will have green roofs. In 2006, the D.C. Department of Energy and Environment (DOEE) launched the “RiverSmart Rooftops Green Roof Rebate Program” to give grants that encourage the installation of green roofs on private property. The grants offer $10 per square foot and up to $15 per square foot if the building is in target watersheds. With no cap on project size, all properties are eligible including residential buildings. To encourage small buildings to install green roofs as well, the program gives funds to offset costs of structural assessments to buildings of under 2,500 square feet (DOEE, 2017a). This incentive plays a large role in the growth in green roof installation per year in D.C. In 2005, building owners installed 0 square feet of green roof as compared to 104,068 sq feet of green roof installed in 2006, the first year of this initiative (DOEE, 2017b). In 2015, D.C. implemented a whopping 712,493 square feet of green roof. Though there is some variation, there is a general increase in total green roof area in Washington D.C. (DOEE, 2017c). An incentive program similar to this on the federal level would increase the total area of green roofs on a broader scale.

Installing green roofs in urban environments is cost-effective. They reduce the amount of pollution in air, improve the health of people living in urban cities, and can be less expensive to install with the implementation of governmental incentives & policies. If all rooftops in Chicago were covered with intensive green roofs, a projected 2046.89 metric tons of pollutants would be removed (Yang et al., 2008).

When discussing the green roofs ability to improve human health, the concentrations of pollutants most commonly discussed in the literature are O3, SO2, particulate matter, and NOx   (Agra, 2017; Clark et al., 2005, 2008; Rowe, 2011; City of Los Angeles, 2006; Rosenfeld, 1998; EPA, 1998) By installing green roofs, the four main pollutants would decrease in concentration enough to create improvements in human health and economic benefits in the reduction of human mortality.  Worker productivity and health is improved along the way, as employees that have a view of nature scenery were less stressed, had lower blood pressure, reported fewer illnesses, and experienced greater job satisfaction (Kaplan et al., 1988; Ulrich, 1984).

The cost-benefit analyses discussed how implementing green roofs would result in savings of a million dollars a day from decreased air conditioning, an overall annual benefit of $895–3392 for each 2000 ft2 green roof, and a reduction in the particulate emissions of one car for a whole year per square meter of green roof. Green roof financial incentives in Washington D.C. greatly increased the total area of green roofs in the area (DOEE, 2017b). An incentive program paired with indirect incentives would be successful if emulated on a federal level. The U.S. has proven that federal environmental policies can be effective as show by the Clean Air Act (EPA, 2015).

Even though green roofs cost 2-3 times as much as a bare roof to install, government incentives can alleviate these costs to bring installation prices down. With the upfront costs lowered, we can reap the benefits of financial, health, and environmental pay-off by green roofs.

AUTHORS

Matas Rudzinskas – Environmental Science

Aaron Lutz – Turf Grass Science

Tara McElhinney- Natural Resource Conservation

 

REFERENCES

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Akbari, H., Pomerantz, M., & Taha, H. (2001). Cool surfaces and shade trees to reduce energy use and improve air quality in urban areas. Solar Energy, 70(3), 295-310. doi:10.1016/s0038-092x(00)00089-x

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Clark, C., Adriaens, P., & Talbot, F. B. (2008). Green Roof Valuation: A Probabilistic Economic Analysis of Environmental Benefits. Environmental Science & Technology, 42(6), 2155-2161. doi:10.1021/es0706652

Clark, C., Talbot, F.B., Bulkley, J., & Adriaens, P.. (2005). Optimization of green roofs for air pollution mitigation Proc. of 3rd North American Green Roof Conference: Greening Rooftops for Sustainable Communities, Washington, DC. 4–6 May 2005, The Cardinal Group, Toronto (2005)

Currie, B. A., & Bass, B. (2008). Estimates of air pollution mitigation with green plants and green roofs using the UFORE model. Urban Ecosystems, 11(4), 409-422. doi:10.1007/s11252-008-0054-y

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Department of Energy and Environment. (2017d). RiverSmart rewards and clean rivers IAC incentive programs. Retrieved from https://doee.dc.gov/greenroofs

Department of Energy and Environment. (2017e). Stormwater retention credit trading program. Retrieved from https://doee.dc.gov/src

Dunnett, N., & Kingsbury, N. (2010). Planting green roofs and living walls. Portland: Timber Press.

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Green the Heat

Evan 95 Comments

 

Image result for green roofs

Green roof in city (Klinkenborg, 2009).

 

Tall buildings consisting of dark roofs and roads with black asphalt remove much of the vegetation that used to thrive there. It is now evident that these changes in the landscape caused severe environmental challenges. Urban areas became vulnerable to the impacts of climate change and the rapid expansion of the population only worsened the cause because of the demand for new accommodation made it normal to ignore existing problems. According to the U.S Census Bureau, 62.7 percent of the U.S. population now live in urban areas (“U.S. Cities are Home to 62.7% of the U.S. Population but Comprise 3.5% of Land Area”, 2015). Many of the environmental challenges in urban areas can be seen in forms of temperatures rising, worsening the urban heat island effect, and pollution from the release of CO2 into the atmosphere. All causing major health threats to citizens living in these areas and more sadly affecting children and the elderly who in many cases were diagnosed with heat related illnesses. Continue Reading →

Green Roofs Effects on Urban Environments

Evan 18 Comments

 

 

Green roof, in France

Isabelle Kendall, Hasan Sabri & Bailey Michell

People over 65 make up a significant portion of the United States population, and the number increases every year. By 2040, the amount of people 65 and older in our population will go from 41 million to around 80 million (Kenney, Craighead, & Alexander, 2014, p. 6). This demographic is at great risk for heat related illnesses and death due to the increasing heat indices of our planet (Conti et al., 2005). A heat index is what the combination of temperature and humidity feel like to human beings, and as temperatures rise so do indices (National Oceanic and Atmospheric Administration [NOAA], 2016). Although the elderly are the most afflicted by heat induced mortality, it can happen to anyone: young or old, rich or poor. Heat waves in Chicago, Tokyo and many other cities have caused fatalities among a variety of individuals. For instance, in the summer of 2003, over 70,000 Europeans passed away during a single heat wave (Knox, 2007). Heat waves are becoming more frequent and more devastating. During a heat wave in Chicago there were nearly 700 more heat related deaths recorded than during a heat wave one year before (Whitman et al., 1997). The increased temperatures that lead to heat related fatalities and other heat related injuries are caused by the expansion of cities across the globe, and more specifically, the materials used to construct these expansions. Materials used include gravel, cement, and asphalt. These impermeable substances that make up urban surfaces like sidewalks, roads, and traditional buildings’ roofs absorb and retain solar radiation during the day then release heat gradually at night increasing surrounding air temperatures into the next day (Knox, 2007). This temperature phenomenon is called the urban heat island (UHI) effect because it causes temperatures in urban areas to be much higher than those in the rural areas around them (Environmental Protection Agency [EPA], 2016). During summer months, the surface of a conventional roof can be as much as 50 º C (90 º F) hotter than ambient air temperatures (Liu & Baskaran, 2003). An article from the Population Reference Bureau (PRB) states that in the 1800s, only three percent of the world’s population lived in cities. By 2008, half of the global population lived in cities, and by 2050, almost 70% of the world’s population will be urbanized (Population Reference Bureau, n.d.). Since the population is continuously growing, it is plain to see that any problems facing cities now will affect a staggeringly larger proportion of people over time. Thus, finding solutions to those problems like heat waves, which occur most frequently in cities, will be an integral part of future city living. Continue Reading →

The Importance of Being Green: Green Roofs Help Urban Inhabitants Breathe Easier

Evan 16 Comments

 

Green roofs have become a popular amenity in cities as city dwellers seek environmentally friendly places to work, live and breathe.

 

Rachel Eckenreiter, Animal Science

Justin Esiason, Environmental Science

Patrick Meehan, Building Construction Technology

 

     As the sun rises in Beijing, the workforce can be seen flowing into the arteries of the city to start the day. The streets steadily fill with people, some whizzing by on bicycles, others on foot as the sun fights through toxic haze and dust. A father and daughter navigate through the dense crowd, completely unfamiliar with the language spoken around them and written on street signs, the young girl quickly glances around her, confused and overwhelmed. Faces of many sizes, ages and shapes glide by, most clad in white medical masks. Her eye catches something they’ve seen before: the welcoming sign of their hotel.  The bright and quiet lobby is cool and clean as they head toward the elevator. Once in the room, she wastes no time and heads straight for the bathroom sink, with the sensation that her face is covered in grime as if she had worked in a dry dirt field all day. After washing her face, she glances down to find that the pristine white hand towel had turned mostly dark grey and brown. Although their stay in China was only three weeks long, it was enough time to recognize that the city of Beijing had a major air pollution problem. (Rachel Eckenreiter, Personal Communication, April 6, 2017). Continue Reading →

Building Green Cities: Mitigating the Urban Heat Island Effect with Green Roofs

Evan 17 Comments

Authors: Jill Banach (Environmental Science), Michael Mason (Building Construction Technology), Mitchell Good (Urban Forestry, Natural Resource Conservation), Sydney McGrath (Horticulture)

A short film, Brooklyn Farmer documents a group of urban farmers growing food on the rooftops of New York City. The head farmer, Ben Flanner, kneels in the dirt cutting fresh salad greens to send to restaurants later that day. As he glances up, the earthy green plants and brown soil contrasts starkly with the concrete skyscrapers on the horizon. He acknowledges that “the city itself has made it possible to do this by being so overbuilt and having all these impermeable surfaces that need sponges on them” (Cherrie & Tyburski, 2013, 6:24). Ben and his team set out to build the world’s largest rooftop farm. With success, two rooftops in the city are now abundant with tomatoes, herbs, root vegetables, and even beehives. Qwen Schantz, another essential person of the operation, describes the potential for future innovation: “When I look out at New York City rooftops and I see thousands of acres of empty space, I truly am moved to cover them with vegetation. And I think that this is something that has to happen. And I think it’s something that will happen” (Cherrie & Tyburski, 2013, 24:47). As the sun sets behind the New York skyline, Ben knows that this farm is making a difference in people’s lives. He is bringing the people of Brooklyn closer to their food, increasing vegetation in a way that is “flashy and weird and interesting” (Cherrie & Tyburski, 2013, 6:57), and contributing to the greater movement of green roofs to reduce the impacts of urbanization. Continue Reading →

Economic Benefits of Urban Green Spaces

Evan 21 Comments

 

 

 

 

 

 

 

 

 

 

 

 

 

Persuasive Research Paper

Of

Economic Benefits of Urban Green Spaces

Luke Fontes, Kevin O’Halloran, William Reich

 

NATSCI 397A Professional Writing

Evan Ross

December 4, 2014

 

 

 

 

 

 

 

 

Urban Green Spaces and the Green Industry

The economic and ecological benefits of urban green spaces are undeniable. The green industry is one of the fastest growing segments of the nation’s agricultural economy and has produced roughly 1,964,339 jobs, according to a USDA-funded research report (Hall, Haydu, & Hodges, 2011). The green industry is made up of green roof construction, sustainable landscaping, waste reduction services, arborists, garden centers, lawn care services, and many more (Hall, Haydu, & Hodges, 2011). In the most simplistic terms, the green industry are economies that striving towards a more sustainable development. Adopting policies that advocate for the green industry and green spaces in Springfield, MA would improve the economy and environmental health of the city and its inhabitants. These policies would act as solutions to some of the environmental problems that municipalities encounter, due to the natural benefits of green spaces.

The development of our natural environment into an urban landscape has eliminated vegetation that is crucial to a healthy and sustainable environment (Carter & Fowler, 2008). There are a number of ways in which green spaces can be effectively implemented into a urban environment. Ranging from green roofs to rain gardens between roadways, each serves an important purpose in a larger system. The Environmental Protection Agency (2014) defines green spaces as areas with any type of vegetation, whether it is grass, shrubs, or trees. However, for the sake of this paper, we will be referring to solely green roofs and sidewalk rain gardens when discussing urban green space. Urban green spaces are often made for recreational areas or for simple aesthetics, but there are a number of ways in which green infrastructure can also contribute to assist in resolving many environmental issues, such as storm water runoff and greenhouse gasses, while also having a monetary gain through savings (Gale, 2014).

Often when people envision green roofs they imagine a flourishing green garden. While sometimes this may be the case, the design and construction of green roofs vary depending on many factors. For example, the climate, orientation, location, and building characteristics are all considered when deciding the appropriate green roof to implement (Hilary, 2014). Green roofs are broken down into two different types, extensive and intensive. Extensive green roofs follow more simplistic requirements, and are often used on single and multi family residential homes. The planting medium usually ranges between 2-4”, and minimal vegetation is used to limit roof loads and maintenance needs. According to Hilary, the benefits of extensive green roofs are mainly water use and thermal advantages, with the intention of keeping overall weight low and requiring access only during maintenance. Hilary continues to discuss how intensive green roofs are more lavish and aesthetically pleasing, and typically are used on commercial buildings. Planting mediums range between 6-10”, and includes vegetation such as grasses, ground covers, shrubs, flowers, and even trees. Some intensive green roofs even include walkways and sitting areas, encouraging people to utilize the gardens. Intensive green roofs require additional maintenance because of the diverse variety of vegetation they support. Commercial buildings are ideal for intensive green roofs because they have higher roof loads that allow for human activity and higher abundance of materials. Intensive green roofs are often referred to as “rooftop gardens”(Hilary, 2010).

Municipal Problems

Xie, Zhang, Zhang, Zhang, & Zhang (2012) argue that urbanization has interfered with the natural process of rainwater filtration, and in turn has lead to polluted runoff that is re-entering our waterways. There are a number of environmental circumstances that affect rainwater runoff. For example, type of precipitation (rain, snow, sleet), intensity of precipitation, duration of the precipitation, and amount of precipitation, to name a few (Speak, Rothwell, Lindley, Smith (2013) . Also, the buildings and structures in urban environments are predominantly made of impervious surfaces. Impervious surfaces are artificial structures such as sidewalks, roads and buildings made of materials that prevent rainwater to infiltrate into the ground (Xie et. al 2012). Impervious surface interrupt the natural filtration cycle of water, which leads to storm water pooling that gets redirected to the municipal sewage systems. The storm water collects pollutants as it runs down the buildings and flows along these impervious surfaces. In the process, unwanted contaminants are collected in the runoff and directed into the sewage systems as well (Xie et. al 2012). Our sewer systems are intended to divert rainwater from the streets, directing it to wastewater treatment plants and our natural waterways, ensuring that lakes and rivers remain at a capacity able to sustain life. However, these wastewater treatment plants are directing contaminated water from these urban areas into these lakes and rivers, harming the natural environment. MAKE BLOCK FORMAT- Why is storm water pollution so bad? As polluted water makes its way to the oceans, water quality can be affected, which often results in the closing of local beaches due to unhealthy water conditions. Storm water carries disease-causing bacteria and viruses. Swimming in polluted waters can make you sick. A study in Santa Monica Bay showed that people who swim in front of flowing storm drains are 50 percent more likely to develop certain symptoms than those who swim 400 yards from the same drain. Illnesses generally associated with swimming in water contaminated with urban runoff include earaches, sinus problems, diarrhea, fever and rashes. Polluted storm water can also hurt aquatic life. Cigarette butts, the number one most littered item in America, have been found in the stomachs of fish, birds, whales and other marine creatures that mistake them for food. The plastic loops that hold six-packs of beer or soda together can strangle seabirds. (United States Environmental Protection Agency, 2014)

Urbanization not only takes away the landscapes ability to absorb water; it has caused problems within our atmosphere and environment with the reduction of vegetation in favor of large buildings, structures, and streets (e.g. impervious surfaces). Without the vegetation we lose carbon sink, which causes an abundance of unwanted greenhouse gas.   A “sink” is a naturally occurring part of the environment that absorbs gases and particulates from the air, with the largest being the worlds oceans and vegetation (“Trees Reduce Air Pollution”, 2011). Sinks are the opposite of “sources”, which add carbon and other gases to the air, such as the burning of fossil fuels. Urbanization indirectly causes a net increase of carbon dioxide and other greenhouse gases, which contributes to global warming. There is typically more air pollution in urban and developed areas caused by burning fossil fuels with the extra amount of activity. Therefore, resulting in high emissions from industrial and manufacturing processes to contribute with pollution coming from households. The added air pollution and the lack of vegetation to remove the particulates and gases from the atmosphere results in what is called the heat island effect.

The heat island effect is a phenomenon that occurs in more developed and urban areas in which the temperature is hotter than in the surrounding suburban and rural areas. In some cases the difference in temperatures can be as high as 22 degrees Fahrenheit (Environmental Protection Agency, 2014). The urban heat island effect can result in numerous negative side effects for residence of the community. For example, higher temperatures result in greater energy consumption and air conditioning costs, and in the most extreme conditions can even result in health complications (EPA, 2014).

Our Proposal

Urban green spacing is economically beneficial due to the positive effects it can have on the environment and human health. We chose Springfield to be the location that we work toward making a greener city. We felt that Springfield would be an appropriate city to implement this plan because its is still a developing city. To do so we want to use both green roofs and sidewalk planter boxes because they are the beneficial economically and environmentally. We want to install two policies in the city of Springfield to enforce the use of green roofs, with the first being that any new buildings should be required to have green roofs. This makes it so that owners have no choice of not using green roofs, whether it is for a preference of other sustainable rooftop system or opposition due to cost. The second policy is that every street should implement green space in the form of storm water retaining planter boxes. This encourages natural filtration of the rainwater into the soil rather than redirecting the water along the street into the municipal sewage system. Along with the resulting economic and environmental benefits of these policies, there will also be an aesthetic benefit. Much like what was done in the city of Toronto, green roof projects will be given grants at a value of $50.00 per m2 of green roofs up to a total of $100,000 to assist with construction costs (Toronto.ca).

How This Affects You

As we have discussed thus far urban development has been the cause of many environmental downfalls. Therefore, it is important that the people living in these communities are well educated about the problem, and also how they can partake in the solution. An effective way in any situation to create awareness amongst a community is when there is opportunity for economic benefit. The impacts of green roofs economically affect residents in many ways. By implementing green roofs and other vegetation you are reducing energy consumption through heating and cooling costs .In a study conducted by the City of Chicago Department of Environment (2003), green roofs were found to reduce roof temperature fluctuations by about 8 degrees compared to traditional roofing materials, making for a more consistent interior temperature.   This of course would be dependent on the type of green roof being used. Intensive green roofs range from 6-10” of soil with vegetation, while extensive green roofs range from 2-4” and have minimal vegetation. In a study conducted by Carnegie Mellon University (2011) about the thermal performance of green roofs on two campus buildings, they were able to conclude that the green roof improved the thermal performance of the roof by reducing heat gain in cooling months and reducing heat loss in heating months. In the heating months of 2009 and 2010, it was found that on average, 26% less heat was lost from the green roof than was lost from the control roof (Becker & Wang, 2011). Also, the presence of plants and growing media reduces the amount of solar radiation reaching the roof’s surface. In doing so, you are also decreasing roof surface temperatures and heat influx during warm-weather months (Becker & Wang, 2011). This again is dependent on the type of green roof and the consistency.

The hidden and more indirect benefits of having green spaces that we cannot put a price tag on, is our health. There are two sides to this, your mental and physical health. Urban areas are usually characterized by cement buildings, asphalt roads, and virtually no trees or other forms of vegetation. In a project put together by Ph.D. K. Flora and K. Wolf (2010) they claim that “urban nature, when provided as… walkways and incorporated into building design, provides calming and inspiring environments and encourages learning, inquisitiveness, and alertness… Planter [boxes], gardens, green roofs, and other features can be incorporated into building design to address mental health and cognitive function.” This study shows that having planter boxes on the side of the road would be conducive to improving people’s mental health. Also, in a study published in BMC Public Health (2010) it was found that, compared to walking or running in urban environments, physical activity in green spaces led to decreased anger, fatigue, and feelings of depression in addition to increased attention levels. The benefits to your mental health are less documented and recognizable than physical benefits, but studies have been done to conclude the benefit.

Urban green spaces also help to increase workplace satisfaction and productivity. One study found that Employees with an outside view of plants experience less job pressure and greater job satisfaction that workers viewing man made objects. These same workers also reported fewer headaches and other health conditions that workers without a natural view. Another study by the Virginia Cooperative Extension (2009) claimed that psychologists have found that access to plants and green spaces provides a sense of rest and allows workers to be more productive, thus bringing in more money for the company

The physical health benefits that come from green roofs and planters boxes are mostly respiratory, and again, hard to give a monetary value. This can be attributed to the better air quality that results from more vegetation in urban areas. The vegetation isn’t just a carbon sink; the particulates that you can breathe in can be in the form of smoke, ash, dust, pollen, and pollen (Maryland DNR, 2009). All of these particulates can harm your lungs, and there are many gases and other particles that are absorbed through trees that could proven to be carcinogenic. Some of the gases that are absorbed from the atmosphere are known to be harmful such as carbon monoxide and sulfur dioxide, and in turn oxygen is released leaving our air more fresh and healthy for us to breathe (“Trees reduce Air Pollution”, 2011). Having more vegetation around would lead to fewer people with respiratory diseases and other illnesses.

 

What Has Worked Elsewhere

Some cities such as Toronto have already began to make progress towards a more sustainable future by implementing green strategies and policies. In 2008, the City Council put in place a strategy for climate change adaptation, as well as placed an increasing importance on the creation of a city that is “resilient to the projected effects of climate change”(City of Toronto, 2009). In doing so, the city changed and introduced environmental policies into their official plan. The following year in 2009 the City Council approved the Toronto Green Standard, a two-tier set of environmental performance measures applied during the planning process to create more sustainable developments and help build a resilient city. The Toronto Green Standard is an important performance management tool for new development, aimed at lessening future infrastructure demands and environmental impacts. Also during 2009, Council adopted the City’s Green Roof By-law, making Toronto the first City in North America to have a by-law to require and govern the construction of green roofs on new development. Overall, Toronto has paved the way for other cities when it comes to innovative and progressive sustainable strategies. The Toronto Green Standard integrates environmental performance requirements established through City policy, guidelines and regulations (City of Toronto, 2008). By making sustainability part of the Official plan of the city, they have set the precedent for others that are interested in striving towards a more resilient and sustainable community.

Urban green spaces can also help increase the property value of a building. The additional aesthetic benefit of the green space is attributive to its other functions. The increase in property value as a result of green space has been proven and documented in numerous studies. In an article by Smart Money Magazine (2003) it is shown that consumers value a landscaped home up to 11.3% higher than its base price. This is an incentive for business owners and municipalities to get excited and involved with sustainability movement. Also, in the study The Freeway Roadside Environment (2000), conducted by the University of Washington College of Forest resources, three neighborhoods in Boulder Colorado indicated that property values decreased by $4.20 for each foot away from a green space.

The ability of these practices to deliver multiple ecological, economic and social benefits or services has made green infrastructure an increasingly popular strategy in recent years (Philadelphia Water Department, 2014). While many cities have already made giant steps towards a healthier, more sustainable environment, others are now following having seen the benefits these cities are experiencing. The industry association Green Roofs for Healthy Cities announced last fall in a press release that Toronto’s green roof requirements had already resulted in more than 1.2 million square feet (113,300 square meters) of new green space planned on commercial, institutional, and multifamily residential developments in the city (Benfield, 2012). According to the association, the benefits will include more than 125 full-time jobs related to the manufacture, design, installation and maintenance of the roofs; reduction of more than 435,000 cubic feet of storm water (enough to fill about 50 Olympic-size swimming pools) each year; and annual energy savings of over 1.5 million KWH for building owners (Benfield 2012). On the other hand, cities such as Philadelphia are following Toronto’s lead and have began to take part in the process.

The city of Philadelphia has a vision to “protect and enhance our watersheds by managing storm water runoff with innovative green storm water infrastructure throughout our city, maximizing economic, social, and environmental benefits for Philadelphia”(Philadelphia Water Department, 2014). Philadelphia has also taken some big strides towards getting the community involved In the process of doing so. Philadelphia put into effect a number of different strategies to get the community engaged. Businesses committed to storm water reduction and management can earn storm water credits, recognition, and other rewards. Community groups, institutions, neighborhood associations and others are invited to partner on watershed protection programs. Toronto’s initiative to strive towards a more sustainable future has hopefully began a revolution. What Toronto has accomplished, and what Philadelphia is currently working in the direction of is admirable. By encouraging the participation of both the municipality and the community, we hope to make sustainability part of every city’s Official Plan.

 

Resistant Audience

When it comes to green roofs like any innovative technology, you are going to face opposition. While the benefits of green roofs seem to outweigh the downfalls, there are still some opposition that needs to be addressed. One opposing argument against green roofs is going to be costs. The initial estimated costs of installing a green roof start at $10 per square foot for simpler extensive roofing, and $25 per square foot for intensive roofs. Annual maintenance costs for either type of roof may range from $0.75–$1.50 per square foot (Environmental Protection Agency, 2013). While the initial costs of a green roof is more than that of a conventional roof, you will soon begin to see the payback through lower energy consumption, storm water management costs, and potentially through a longer life cycle than that of a conventional roof.   A University of Michigan study (2008) compared the expected costs of conventional roofs with the cost of a 21,000-square-foot (1,950 m2) green roof and all its benefits, such as storm water management and improved public health from the absorption of unwanted greenhouse gases. The green roof would cost $464,000 to install versus $335,000 for a conventional roof. However, over its lifetime, the green roof would save about $200,000,nearly two-thirds of these savings would come from reduced energy needs for the building with the green roof (Environmental Protection Agency, 2013). However, when installing a green roof you are doing it for the environmental value rather than the monetary value, but not everyone follows these same morals. Another opposing argument is the effectiveness of green roofs. However, this argument is easily rebutted by factual evidence and numerous case studies, and is equivocal to people arguing the legitimacy of global warming.

The implementation of these environmental policies and strategies into the overall plan of our cities is necessary. Green roofs are becoming popular in the United States, with roughly 8.5 million square feet installed or in progress as of June 2008(Environmental Protection Agency, 2013). With the levels of energy consumption and pollution that are a result of our urban environments, we need standards in place to assure we are working towards a more sustainable future. The benefits of going forward with urban green space is undeniable, and outweighs the opposing argument. In conclusion, we are involved in the beginning of a movement something that is essential to the well being of our future environment. With the education and participation within each local community, we can begin to move in the right direction.

 

Reference List

 

Becker, D. & Wang, D. (2011, May 12). Retreived from http://www.cmu.edu/environment/campus-green-design/green-roofs/documents/heat-transfer-and-thermal-performance-analysis.pdf

 

Benfield, K. (2012, April 25). Toronto’s leadership for green roofs. [Web log comment]. Retrieved from http://switchboard.nrdc.org/blogs/kbenfield/torontos_leadership_for_green.html

 

Bowler, D., Buyung-Ali, L., Knight, T,.& Pullin, A. (2010) A systematic review of evidence for the added benefits to health of exposure to natural environments. BMC Public Health 10. doi:10.1186/1471-2458-10-456

 

Carter,T. & Fowler, L. (2008). Establishing green roof infrastructure through environmental policy instruments.Environmental Management 42, pp.151-164. doi: 10.1007/s00267-008-9095-5

Evans, E. (n.d.). Trees of Strength. Retrieved from http://www.ncsu.edu/project/treesofstrength/benefits.htm

 

Hall, C., Haydu, J., & Hodges, W. (2011). Economic impacts of the green industry in the United States. Retrieved from http://edis.ifas.ufl.edu/fe566

 

Featured story: Stormwater runoff. (2013, November 25).Retrieved from http://www.epa.gov/region9/water/npdes/stormwater-feature.html

 

Flora, K. & Wolf, K. (2010, December 10). Mental health & function. Retrieved from

http://depts.washington.edu/hhwb/Thm_Mental.html

 

Green roof bylaw. (n.d.).Retrieved from http://www1.toronto.ca/wps/portal/contentonly?vgnextoid=83520621f3161410VgnVCM10000071d60f89RCRD&vgnextchannel=3a7a036318061410VgnVCM10000071d60f89RCRD

 

Green stormwater infrastructure. (2014).Retrieved fromhttp://www.phillywatersheds.org/what_were_doing/green_infrastructure

 

Heat island effect. (2014, July 31). Retrieved from http://www.epa.gov/heatisland/

 

Hilary, D. (2010, July 31). Intensive vs extensive green roofs: what’s the difference? Retrieved December 3, 2014, from http://www.greenroofplan.com/intensive-vs-extensive-green-roofs/

 

Lindley, S., Rothwell, J., Smith, C., & Speak, A. (2013, January). Rainwater runoff retention on an aged intensive green roof. Science of the Total Environment, 461, pp. 28-38.

DOI: 10.1016/j.scitotenv.2013.04.085

Net Benefits and Costs of a Green Roof on John Crerar Library over 40 Years at a 6% Discount Rate. (n.d.). [Graph illustration of cost and benefit analysis] Global Reference on the Environment, Energy, and Natural Resources Online Collection. Retrieved from http://find.galegroup.com/grnr/infomark.do?&source=gale&idigest=f1eac380167b7605799a391ef47d98d2&prodId=GRNR&userGroupName=mlin_w_umassamh&tabID=T011&docId=GD3208730906&type=retrieve&contentSet=GREF&version=1.0

 

What is open space/green space? (2014, May 6). Retrieved from http://www.epa.gov/region1/eco/uep/openspace.html

 

Relf, D. (2009, May 1). The value of landscaping. Retrieved from http://www.dnr.state.md.us/forests/publications/urban2.html

 

Temperature fluctuations at membrane horizon by roof type. July 15-20, 2003. (2004). [Graph illustration of temperature fluctuations on roofs]. Global Reference on the Environment, Energy, and Natural Resources Online Collection. Retrieved from http://find.galegroup.com/grnr/infomark.do?&source=gale&idigest=f1eac380167b7605799a391ef47d98d2&prodId=GRNR&userGroupName=mlin_w_umassamh&tabID=T011&docId=GD3208730905&type=retrieve&contentSet=GREF&version=1.0

 

The value of green infrastructure. (2010). Retrieved from http://www.cnt.org/repository/gi-values-guide.pdf

 

Trees reduce air pollution. (n.d.) Retrieved from http://www.dnr.state.md.us/forests/publications/urban2.html

 

Wolf, K. (2010) The freeway roadside environment: Testing visual quality at the road edge.Retrieved from http://www.naturewithin.info/Roadside/Rsd-Prefs-FS9.pdf

 

Xie, G., Zhang, B., Zhang, C., & Zhang, J. (2012). The economic benefits of rainwater-runoff reduction by urban green spaces: A case study in Beijing, China. Journal Of Environmental Management, 100, pp. 65-71.

DOI: 10.1016/j.jenvman.2012.01.015

 

Integrating Green Spaces Into the Urban Environment

Evan 16 Comments

wynnpic

Christopher Tran, John Waters, Dario Kantardzic

Prof. Evan  Ross

NATSCI 397A

December 2, 2014

 

As the human population grows within cities, the issue of overpopulation leads to increased urbanization. In a study titled, Effects of spatial form on urban commute for major cities in China (2014) , Zhao et al claim, “City compactness can be measured simply using urban spatial form or morphology: the more concentrated the built-up area, the more compact the city is” which shows the more people per square footage leads to a more crowded city. The many conveniences that buildings within cities offer attract large crowds of people in order to live, work, and attend school. Continue Reading →

A Proposition to Decrease Urban Obesity through Aquaponics and Urban Repurposing

Evan 19 Comments

We hear about them all the time: Food crises across the world. From the comfort of our couches, we’ve all seen the commercials with the host explaining the plight of starving children; their environment and lack of food, school, and many basic necessities. These people come from places that we couldn’t find on a map if we tried. Half paying attention, we’re looking at our Facebook feed, walking over to the thermostat and turning it up to a comfortable seventy degrees. During the drive to work or school, a story is on the radio about food riots in Libya as we take another sip of our Starbucks Iced Hazelnut Macchiato. So far away, it seems almost like a dream, these places we’ve never come close to experiencing; we believe that this is the one and only face of starvation and malnutrition, how fortunate we are to live in a country that doesn’t have that problem. Continue Reading →

Green roof designs with major American cities

Evan 36 Comments

Brianna Ramsey – Environmental Science

Brandon Parker – Sustainable Horiculture

Richie Frend – BCT

Chicago city hall initiates green roof implementation within U.S. cities (McDonough, 2004).

Chicago city hall initiates green roof implementation within U.S. cities (McDonough, 2004).

 

The Urban Heat Island Effect is not a newly found issue, yet America has done little to combat the main causes of this problem.  The Urban Heat Island (UHI) effect is only becoming more and more evident as cities continue to grow.  Fighting this issue with real action is essential to improving the living quality in large American cities.  Yilmaz et. al. (2009) gets to the root of this problem by stating that “as cities continue to grow and develop under climate change, identifying and assessing practical approaches to mitigate high urban temperatures is critical to help provide thermally comfortable, attractive and sustainable urban environments.”  Much of the reason the Urban Heat Island effect has passed by under the radar is that during day to day activities the threat is not eminent, therefore is goes unchecked.

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Urban Heat Island Effect in Los Angeles: Using Albedo to Reverse the Trend

Evan 15 Comments
Retrieved from: http://www.lternet.edu/research/keyfindings/urban-heat-island-effects

Retrieved from: http://www.lternet.edu/research/keyfindings/urban-heat-island-effects

By: Sana Jameel and Daniel Scorpio

2003 European Heat Wave

Natural disasters, such as floods, lightning strikes, tornadoes, and hurricanes have devastated human lives across the world. These types of weather events often make headline news and, depending on the severity of the incident, take extended amounts of time to recover. However, heat waves, on average, take more lives than floods, tornados, hurricanes, and lightning strikes combined (National Oceanic and Atmospheric Administration, n.d). August 2003 was unusually warm for the continent of Europe. A heat wave impacted the region for many weeks, taking approximately 35,000 lives. The most affected by the increased temperatures were the young and the elderly, with heat stroke being the major cause of death. According to Campbell (2009), August 10th was the hottest day of the month with a temperature of 37° C (p. 6). This particularly devastating weather event is attributed to increased global warming (Campbell, 2009, p. 7).

What is The Urban Heat Island Effect?

            Although the 2003 European heat wave seems like an extreme example of elevated global temperature, developed worlds are experiencing similar warming trends in a number of cities known as the urban heat island effect. As stated by the Environmental Protection Agency (2003), the urban heat island effect is the phenomena that urban settings are becoming increasingly warmer than their surrounding rural areas. Atmospheric temperatures in cities experiencing an urban heat island can be as much as 5.6° C warmer than their rural counterparts (p. 2). This occurs because there are large amounts of grey spaces when compared to the scant amount green spaces in cities. Unlike vegetation and trees, which transfer heat into energy and provide shade to surfaces, structurally developed areas absorb heat to only slowly release it later in the day.  When solar radiation reaches the surface of an urban environment during the day, the heat is more readily absorbed by pavement, building walls, and rooftops. At night, the heat is slowly released from the materials that absorbed it during the day, warming the urban atmosphere as well. On the contrary, rural landscapes with more green space, are able to reflect more sunlight back into the atmosphere or use the solar energy for photosynthesis, turning the heat into energy and allowing the area to remain relatively cooler (Environmental Protection Agency, 2003, p. 2). As the Environmental Protection Agency (2003) explains,  the urban heat island effect poses a public health issue because, as the European heat wave of 2003

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