Background
A green environment includes the geographical area and the natural state that has not yet been developed and development must not negatively impact the existing infrastructure and the environment.
The design of green cities needs various environmental programs and suggestions from a multi-agency perspective. Environmental abuse must be reduced. Abuse is exploitation through extraction of raw materials for production without protective measures to restore nature’s former state.
Most cities now are paved with concrete and asphalt where the grasses, trees and plants are not anymore around. Cities should provide a wholesome green environment emphasizing environmental preservation. There are cities which have developed sustainability plans stressing on those areas, like for example, PlaNYC for New York which is a model environmental plan focusing on the environment, economy and equity (Rosan, 2012, p. 960).
An eco-friendly community is one built on many aspects of environmental preservation, that include cleaning up the surrounding; adequate programs for waste management disposal; the presence of different varieties of species on earth, in short biodiversity; reduction of carbon dioxide emissions and pollution; sustainability and the concern for the future needs of the planet (Maczulak, 2010). All these underline the topic on green cities.
Problems of industrial cities
Pollution
The growth of cities has impacted on global sustainability as can be seen on their environmental effects. Urban areas need large volumes of resources which produce more greenhouse gases in the form of methane and carbon dioxide. Industries have exacerbated air pollution. Greenhouse gas (GHG) emission is the number one problem. City planners should focus on reducing GHG emissions with the use of renewable energy.
Pollution has produced a plume spinning the earth (Balaram as cited in Bugliarello, 2011, p. 4). This plume is composed of toxic substances that warm the environment and destroys the ozone layer, our protection from the sun’s ultra-violet rays. Pollution reduces air quality and increases air temperature, exacerbating global warming. The “heat island effect” is created wherein the temperature of the city is higher than the countryside (Bugliarello, 2011, p. 4).
Urbanization
The urban cycle concept is linked with environmental use and abuse. First, agriculture was invented about ten thousand years ago. Cities were formed, knowledge was improved, alongside material and social capital, and then came the discovery of oil, the so-called black gold. The discovery of fossil fuel impacted on industries, technologies, and other social phenomena.
The urban cycle resulted in the production of “negative products,” environmental degradation, urban migration and poverty and the many social ills as a result of migration. With a large population to feed, agriculture has to be improved which resulted in “the development of energy- and fertilizer-intensive industrialized agriculture” (Bugliarello, 2011, p. 5).
Urban migration exacerbates environmental problems and slum areas continue to grow. The emphasis of environmental justice is to focus on these slum areas since many poor families, ethnic communities and so-called marginalized, live in these areas where risks are higher than in the countryside. These risks may be in the form of epidemics which affect other population in adjacent areas.
Cities are the first to experience economic downturns and financial crisis where unemployment worsens. Natural disasters like hurricanes and tropical cyclones also come in handy. New York was a victim of the worst man-made disaster, the 9/11 terrorist attacks (Bugliarello, 2011, p. 4).
Fig. 1: The urban cycle results in so-called “negative products,” environmental degradation and continuous urban poverty with its diseases and social ills. SOURCE: Bugliarello (2011, p. 5)
Sustainability is the application of continual green innovations for the present and future populations. Sustainability of an entity cannot be permanent since there must be continuous interaction and innovation among the different entities or agencies in the city. Urban sustainability must have security, economics, environment and resources, health, and quality of life (Bugliarello, 2011).
If one of these is missing, there is no sustainability and the city cannot be called “green”. Environmental degradation and destruction of the ecosystem are some of the causes of climate change and global warming. Floods and other natural calamities have become a major problem of cities.
Global sustainability programs have not improved because of the world’s dependence on fossil fuel. Renewable energy must be tapped and should be a priority program for cities because this energy resource protects the environment.
Literature Review
The emphasis here is not purely on cities but on areas where there is large migration, which can be a municipality. Sustainability has become a problem for cities and their neighborhood.
Sustainability became a popular term when the World Commission on Environment and Development promoted it in the context of sustainable development, which refers to “meeting the needs of the present and future generations” (WCED as cited in Koo & Ariaratnam, 2008, p. 565).
Sustainable planning and environmental justice (EJ)
Sustainability planning and environmental justice (EJ) for cities must be a coordinated effort between the government and the various sectors of society. EJ communities are the areas where the poor and minority communities reside.
Most cities have an “unequal distribution of environmental risks” (Rosan, 2012, p. 973), where their environmental plans are mostly focused on areas where the middle class reside. For the city of New York, PlaNYC prioritized EJ to make the city “greener and greater” (Rosan, 2012, p. 973).
Application of net-zero buildings
The application of net-zero buildings focuses on the use of sustainable energy resources to reduce greenhouse gas (GHG) emissions. Energy resource in the city should be decentralized and buildings should have their own power generation, using renewable energy in hybridized form (Kilkis (2012, p. 1359).
Fig 2. The energy flow in a building’s energy system. SOURCE: Kilkis (2012, p. 1359)
Figure 1 shows a linear economy model, a strategy usually employed by economists. Kilkis (2012) proposed that this has to be improved because it produces too much waste and “exergy destruction”. This problem can be improved by producing an interlink so that there can be a net-zero status.
A new circular exergy model has to be produced. The term “exergy” is about promoting efficient energy-resource that should be used in buildings determines the generated wastes in the process of producing energy.
Green roof or green roofing is the term applied to buildings with roofs planted with vegetation. Many buildings in urban areas now use green roofing because vegetation and soil can provide coolness in the atmosphere and reduce energy use.
Green roofs serve as catch basin as they reduce “storm water runoff from building surfaces by collecting and retaining precipitation” (Oberndorfer et. al., 2007, p. 824). Green roofs and green buildings have aesthetic and environmental purposes. The U.S. Postal Service building in Chicago has been home to the largest green roof in the country (Stutz, 2010, para. 1-2).
Building designs to bear sustainability principles
Harmony with nature
This means a sound environmental program is to be the main thrust of the building design, which should take into consideration the presence of greenways, like open spaces or parks situated in rivers or historic infrastructure corridors like canals or railroads that connect people with places.
Wholesome environment
A wholesome place to live includes amenities for recreation, health, and fitness through trail activities and people feel like they live in the countryside. The neighborhood should have parks and open spaces that can be used as entertainment areas (Lindsey, 2003, p. 167).
Equity
In cities where the poor and marginalized live, equality and social justice should focus on the lack of the basic necessities for the people to live. Environmental problems in these areas exacerbate social exclusion and social justice.
Sustainable economic development
The Brundtland Commission stressed the need to protect the environment while growth and economic development is ongoing. Providing the basic needs should be a primary concern but must be done in legitimate and democratic ways. Natural systems must not be destroyed in the name of economic development.
Conclusion
The emphasis of making cities greener is to enhance environmental programs. This is related with the concept of sustainability.
Sustainable cities cannot bear the concept of sustainability if they do not focus on the “greening” of the environment. The literature provides many concepts and theories on the greening of cities which are all related to the concept of sustainability. Most cities are focused on economic growth but this has to be environmentally sustainable.
Recommendations
City planning to make the urban areas greener must involve the field of engineering in providing “methodologies, algorithms, and tools for rational decision making” (Sahely et al., 2005, p. 73) since the city usually undergoes continuous changes because of economic development. Cities should promote ecological awareness so that people can actively pursue social and ecological justice.
References
Bugliarello, G. (2011). Critical new bio-socio-technological challenges in urban sustainability. Journal of Urban Technology, 18(3), 3-23. doi: 10.1080/10630732.2011.615561
Kilkis, B. (2012). Net-zero energy cities: A hub for decentralized energy for better environment. International Journal of Energy Research, 36(15), 1358-1365. doi: 10.1002/er.1917
Koo, D. & Ariaratnam, M. (2008). Application of a sustainability model for assessing water main replacement options. Journal of Construction Engineering and Management 134(8), 563-574. doi: 10.1061/(ASCE)0733-9364(2008)134:8(563)
Lindsey, G. (2003). Sustainability and urban greenways. APA Journal 69(2), 165-180. doi: 10.1080/09652110120049271
Maczulak, A. (2010). Sustainability: Building eco-friendly communities. New York: Infobase Publishing.
Oberndorfer, E., Lundholm, J., Bass, B., & Coffman, R. (2007). Green roofs as urban ecosystems: Ecological structures, functions, and services. Architectural Science Publications and Research, 57(10), 823-833.
Rosan, D. (2012). Can PlaNYC make New York City “greener and greater” for everyone?: sustainability planning and the promise of environmental justice. Local Environment, 17(9), 959-976.
Sahely, H., Kennedy, C., & Adams, B. (2005). Developing sustainability criteria for urban infrastructure systems. Canadian Journal of Civil Engineering 32(2), 72-85. doi: 10.1139/L04-072.
Stutz, B. (2010). Green roofs are starting to sprout in American cities. Web.
Wolch, J. (2007). Green urban worlds. Annals of the Association of American Geographers, 97(2), 373-384. doi: 10.1111/j.1467-8306.2007.00543.x