Is just a question of form? Energy, Environment and.....
Massimo Tadi
Professor of Architectural Design
International Master class in Architectural Engineering
Faculty of Building Engineering and Architecture
Politecnico di Milano
Introduction.
This paper sketches out the relationships between urban design and sustainable development". Moreover it emphasises the role of urban design for a sustainable urban development. Over half of greenhouse gas emissions are created in and by cities. 80% of the population lives and works in cities, where up to 80% of energy is consumed. So urban design principle can address the challenges in a comprehensive way, facilitating the conciliation between development and sustainability. The most challenging project for any city is to address both its competitive status and its ecological stewardship. So the paper attempts to establish relationship between energy saving, public transportation development, environmental policies and contemporary urban form searching on some new design principles.
Actually, Energy, Infrastructure, Environment seems to be the new key factors for reaching a sustainable development as well as to better off the quality of contemporary urban life. The paper outlines the profound changes these elements would bring to the urban form.
Global scenario and critical issues.
The demographic increase is a phenomenon that has reached a considerable size during the last century and created, looking forward, a series of questions regarding the overall sustainability of the ecosystem and even some serious doubts as far as its chance for survival is concerned.
Clearly, among the dynamics of our planet, this is the one that, more than others, deeply affects the environment, the availability of natural resources, the organization of the dwelling structures and generally all human activities cumulatively. In order to fully appreciate the size of this problem, simply note that, from the Sixties (1) to the beginning of the 21st century, our planet has recorded its highest rate of demographic increase in its history (2).
It is a trend that, while easing off following its peak in 2003, will lead to double the world population by 2050 compared to the previous 80 years. By then, in fact, the Earth will be populated by 9.2 billion inhabitants, up to 13.2 billion people by 2080 (3).
It is an unstoppable dynamics reminding us of the impacts other processes which are directly or indirectly related to the increase in population will be having on our planet, including some of the most urgent and severe phenomena, such as: the planet's deforestation (4), and its related as well as progressive expansion of the land occupation for agricultural purposes (5); the unstoppable urbanisation processes (6) also associated with the new migration flows, and related to some phenomena of urban sprawling (7) and new land occupation for housing purposes (8); the emissions increasing into the atmosphere (9) and the steady deterioration of the quality of the air, land and water occurring in many regions of the world. It is a series of interconnected phenomena deeply affecting our planet's ecosystem, while changing at the same time the social behaviour in whole groups of people. Such phenomena are global with common characteristics that are shown at a local level with very profound differences and peculiarities in different areas of the world.
Global processes and Local differences.
We will particularly focus on one of the above mentioned phenomena, that is, the acceleration of the urbanisation (10) process occurring in various parts of the world for some years; we will then use such specific observation point in order to understand its relation with the other phenomena and to determine whether and how this phenomenon relates to the increase of energy consumption (11) and emissions into the atmosphere, the urban sprawling as well as the land consumption.
This has the ultimate goal of trying to identify useful principles and tools aiming to direct the increasing world urbanisation towards some sustainable long term models, which are characterised by a better balance between the available resources and the required consumption.
In this respect, it should be underlined that the urbanisation, while being a global phenomenon, can be seen locally in various part of the world, with specific qualities (12) and very different physical results that need to be carefully investigated. In fact, many developing countries, both in Africa and South East Asia are experimenting a fast urbanisation along with a strong population growth (13), whereas in China (14) - where the population growth rate is stable - such phenomenon is mainly boosted by the very strong domestic migration flows generated by the massive economic growth recorded in recent years, which is leading to a great population concentration moving from the countryside to the cities (15).
Conversely Europe, where we will be focusing our attention, appears to be a very peculiar case with many critical elements, while retaining its significant domestic differences mainly between the North-West and South Mediterranean regions. Europe, namely the European Union, shows a significant urbanisation (16) - in line with the global tendencies - that is associated with small increases or demographic decreases, even.
It can also be noted that, in most of the EU, where it assumes the form of a wide urbanisation with a low density, this process is occurring in an environment of economic growth, in a stable economic environment or even during a recession (17).
But "More than a quarter of the European Union's territory has now been directly affected by urban land use; by 2020, approximately 80 % of Europeans will be living in urban areas, while in seven countries the proportion will be 90 % or more".
Source European Commission/Joint Research Centre
Interestingly, while in most of the world's regions the urbanisation is boosted by significant demographic and economical increases and, even when accompanying the already mentioned negative phenomena, it causes increases in the residential density per square kilometre in most cases, we can observe in the European case that the same process of urbanisation, which is instead caused by completely different and sometimes mixed reasons, brings with it also a progressive reduction of the residential density per square kilometre (18) as well as the negative aspects (19) that we mentioned already.
Therefore, the European phenomenon is basically a process of urban diffusion and land occupation occurring when an increase of the general population is lacking (20): "Historically, the growth of cities has been driven by increasing urban population. However, in Europe today, even where there is little or no population pressure, a variety of factors are still driving sprawl. These are rooted in the desire to realise new lifestyles in suburban environments, outside the inner city. Global socio-economic forces are interacting with more localised environmental and spatial constraints to generate the common characteristics of urban sprawl evident throughout Europe today".
Source European Commission/Joint Research Centre
This diffusive process, while changing the substance of the deep foundations of European urban culture, generating a new settlement model (21), for conditions, reasons and arrangements, is actually quite specific and not directly homologous to its low density settlement pattern of North American (22).
A number of existing studies have tried to objectively estimate the social, economical and environmental costs of this new settlement model growingly expanding as well as tried to define, not without some difficulties, any objective and generalizable indicators (23) which are capable of evaluating the social, economical and environmental costs of such model (24).
However, the consensus of most of the same researchers is now that the diffusive model, both in the American and in the more recent European form, has negative consequences in terms of quality of the environment, due to the destruction of biotypes, the fragmentation of ecosystems, the increase of pollutants and CO2 and NOx emissions resulting form the increased use of energy (25), which the model obviously needs.
Also the model requires high social and individual costs, due to building and maintaining infrastructures for private transport (26) as well as the costs of the latter, the high number of road accidents (27) and the ever increasing commuting time.
So "As cities have sprawled ever farther and farther from their cores, this has vastly increased levels of energy consumption (28) not only from transport but even in terms of other sorts of building and household energy distribution costs. Low-density, sprawling cities are two to three times more expensive to provide public services than those cities more densely populated".
Source UN-Habitat Report 2005.
The model proves itself unsustainable in the long term, both in terms of the environment and economically, because of the large amount of energy, environmental and spatial resources it needs and which are unavailable instead.
From a social and cultural point of view, it is incompatible with the sense of urbanity and place that plays an important role in the European culture for shaping any specific cultural identity (29). It is a model that, as well as the physical structure of places, modifies the structure of social relationships too, by reducing the interaction among individuals, amplifying its segregative potential, penalizing some age-related populations such as the elderly and the youth, who are both subjected to the low possibility of individual mobility.
It does it by defining a space which segregates the various human groups (30) according to their ethnicity, age and wealth.
In such space, social cohesion weakens and the individual is emphasized, the weakness in the relationships increases as an inverse proportion of the need for an individual security, a need for security that this model "consumed as a commodity" (F.Munoz) (31).
But then, what is this steadily forming model that, while with its critical elements, seems to be on the verge of replacing the traditional dwelling models of the European city (32)? A model representing a challenge for Europe, according to the European Environment Agency (33): "Urban sprawl is one of the major challenges we face in Europe. A constructive debate and a greater involvement of the EU Institutions in this important field are crucial for the future of our cities" (J. Craig). (34)
The Sprawling process
Squires (2002) defines sprawl as a pattern of urban and metropolitan growth that reflects "low-density, automobile-dependent, exclusionary new development on the fringe of settled areas often surrounding a deteriorating city". He suggested that the term has been used to refer to: patterns of urban development, processes of extending the reach of urbanised areas, causes of particular practices of land use, and to the consequences of those practices. Sprawl is: "a pattern of land use in an urbanised area that exhibits low levels of some combination of eight distinct dimensions of density, continuity, concentration, clustering, centrality, nuclearity, mixed uses and proximity"
(Galster et al 2001, p. 685).
For Nata_a Pichler-Milanovic: "Besides important differences between Europe and the North America, there are also intra-European variations in urban sprawl because of the great diversity in urban cultures in space and time, ....it is difficult to speak about unique European urban sprawl, despite recent similarities of new "hybrid city(land)scapes" in European cities. We can speak of Anglo-American and North-West European variations of urban sprawl, of Mediterranean, Scandinavian and Central European of Balkan variations, of North African, Middle Eastern, or South-East Asian urban sprawl, but even using these terms we have to be cautious, not only because they are inwardly so diverse, but also because of the multiple spatial and temporal explanations of sprawl, which differ in each and every city, objectively and inter-subjectively, among different social classes and interest groups" (35).
(Nata_a Pichler-Milanovic, 2007, p.127)
Thus while noting the specific differences and the different variations that urban sprawl has taken in relation to specific local conditions and different urban cultures, it is necessary to emphasize the difficulty of a precise definition of "quality" of this multi-dimensional phenomenon, perceived and defined locally differently.
Nevertheless it is possible to agree on the magnitude of the process, which clearly highlights the dissipative characteristic that the model contains in all its different declination. Therefore we can say that every sprawling landscapes, hybrid landscapes as well as the cityscapes has to be considered, unsustainable in a long run.
Energy consumption in the urban sprawl: facts.
The dissipative structure of organization of the Urban sprawl has been highlighted by some specific characteristics that the model contains in its own structure, in particular, it determines:
- increase of the level of use of private car and trip lengths
- increase in fuel consumption
- increase in air pollution
- increase of heating/cooling Energy consumption.
Due to the fact that cities, can be treated "as energy-using systems in their own right, with their own varying levels of efficiency and they are not mere aggregations of disconnected consumers of Energy, we are aware that the distribution of users affects energy consumption required for transportation, transmission efficiency"
Mehaffy M. S. Cowan, D. Urge-Vorsat.
To prove it, it is worth noting that per capita use of the energy required for the private transport increases sensibly where the residential density decreases. For example, we can observe the cases of Oslo and Nantes, two among the European cities with a lower rate of residential density per square kilometre, whose position is among the largest European consumers of per capita energy for private transport and, simultaneously, they show a low rate in the use of public transport, but a very high rate of available motorway kilometres per inhabitant. Conversely, Barcelona and Brussels, whose rates of residential density per square kilometre are among the highest, have, in the case of Barcelona, the lowest level - in absolute terms - of energy consumption, whereas both cities show high levels in the use of public transport and a very low amount of available motorway kilometres per inhabitant. The energy consumption for the transport in relation to the residential density per square kilometre calls for another indicator as significant and as related to the former, i.e. the emission of pollutants in the atmosphere. In particular, a relation can be proved between the density of a population and the amount of CO2 emissions into the atmosphere.
Two different studies (36) aiming to compare the relation between residential density and emissions in some selected cities show that both in Europe and, broadly-speaking, in the world, a reduction of the residential density matches a steady increase in the amount of emissions into the atmosphere. "Sprawl also increases the length of trips require to collect municipal waste for processing at increasingly distant waste treatment plants and this is expected to continue as household waste grows 3-4 % annually".
It is worth remembering that a city, as a complex dynamic system, features an energy behaviour (heating/cooling) which changes according to the changes of its whole formal configuration.
It is indeed proved that the morphology of a settlement can determine specific microclimates as well as soften or worsen any local climate aspects, like it happens, for instance, in the so-called "heat islands" (37). In this case, the morphological structure plays a central role that can direct, from the beginning, the energy consumption of the dwelling system through more or less beneficial arrangements for the specific context.
In this respect, the density associated with the compactness proves to define an extremely efficient dwelling system, both in relation to the efficiency of the public transport and the reduction of traffic; it also proves to represent a very efficient organisation where the energy saving of the system exceeds the total of the potential efficiency from its individual components/buildings (38). A dense and compact urban structure, in fact, has in itself an energy efficiency value acting as a multiplier of the performance of its single components. At the same time, the hybrid use of the urban space allows to realize a urban environment whose characteristics are particularly favourable to the light mobility and pedestrianability of travelling. A life-cycle analysis found that CO2-equivalent emissions are 60% less for high-density than for low-density development (39). So "the best policy response seems to be one of selective density increases and mixing of compatible land uses, especially around areas of high public transport accessibility". Kenworthy (40)
So reducing sprawl, play a fundamental role for saving energy, decreasing emissions (41) and improving the social cohesion between its inhabitants, and an importance role for addressing climate change.
The role of the cities between policies and urban design.
Home to 80% of EU citizens and 70% of greenhouse gas emissions, urban areas play a key role in fighting climate change; but cities' access to funding for green policies is proving a major stumbling block.
"Although cities embody environmental damage, namely, increasing emissions due to transportation, energy consumption and other factors, policymakers and experts increasingly recognize the potential value of cities for long-term sustainability, after all, the majority of energy is consumed in cities. Therefore, it is an urban issue." UN-Habitat Report
So how the city can contribute to overall urban sustainability? Can the urban form offer a useful approach to climate mitigation and reducing emission in atmosphere? How to address both its competitive status and its ecological stewardship?
Key factors for reaching a sustainable development.
Jacqueline McGlade, director of the European Environment Agency, speaking to CORDIS News, identified the key issue for energy efficiency and cutting emissions as being urban sprawl. Compact cities, she said, should be preferred over the current practice of planning polycentric developments. urban sprawl could be managed by limiting developments to corridors served by train networks and discouraging car use. In our opinion basic principle for urban design and development of cities environmentally oriented has to adopt design solutions characterized by principles of compactness and densification, supported by the centrality to the collective infrastructures for mobility. Basic environmentally oriented principles such as:
- Promote Density and Compactness.
- Facilitate Mixed used.
- Encourage an efficient Public Transportation System.
- Advance Local Energy production and efficiency.
- Improve relationship between Urban Morphology and Building Typology.
Conclusion
Due to the fact that cities are energy-using systems in their own right, and that they can use energy in dramatically more or less efficient ways. The urban settlement forms can have a disproportionately large effect over the Energy consumption and consequently on any effective long term strategy for reducing C02 emission in atmosphere.
For this reason the compactness of urban settlement forms related with increases in settlement density, mixed uses and by integration of space and supported by a collective hierarchical and highly integrated infrastructure, can generate a settlement model environmentally sustainable in the long period.
This means a city, heir to the European urban tradition, which will be able to combine economic development, quality of life, culture with a strong sense of responsibility towards the environment. A form of settlement in which compactness is a consistent condition and scheme of aggregation between the different parts, structural link for the space components (individually recognizable) which apply the most advanced manufacturing technologies for energy efficiency and emissions cutting. This is a daunting challenge, but a most necessary one
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Notes
(1) The growth rate of the human population has been steadily declining since peaking in 1962 and 1963 at 2.20%. In 2009 the estimated annual growth rate was 1.10%.
(2) "World population is projected to reach 7 billion early in 2012, up from the current 6.8 billion, and surpass 9 billion people by 2050, reveals the 2008 Revision of the official United Nations population estimates and projections, released today. Most of the additional 2.3 billion people will enlarge the population of developing countries, which is projected to rise from 5.6 billion in 2009 to 7.9 billion in 2050, and will be distributed among the population aged 15-59 (1.2 billion) and 60 or over (1.1 billion) because the number of children under age 15 in developing countries will decrease. In contrast, the population of the more developed regions is expected to change minimally, passing from 1.23 billion to 1.28 billion, and would have declined to 1.15 billion were it not for the projected net migration from developing to developed countries, which is projected to average 2.4 million persons annually from 2009 to 2050". From: 2008 Revision of World Population Prospects. See the full results of the 2008 Revision will be issued online at the website of the UN Population Division (www.unpopulation.org).
(3) World population considering the highest scenarios, 2000-2300 World opulation in 2300. Highlights. By Department of Economic and Social Affairs Population division, United Nation.
(4) Statistics on Deforestation by the United Nations Food and Agricultural Organization reveal that the rapid declines could bring the global forest cover to the size of the Asia Sub-continent by 2050. Every year more than 8.5 million hectares of tropical rainforests are being razed. More than 12 million hectares of forest land is lost to urbanization or allied activities each year. This has resulted in a rapid global decline in some regions as Nigeria, Brazil ,Central America, India, Mexico, Philippine, Thailand, Indonesia, Bangladesh, but also China, Sri Lanka, Congo and Ghana have lost much more than 50% of their rainforest cover.
(5) see www.fao.org
(6) see WORLD URBANIZATION PROSPECTS: THE 2005 REVISION. Department of Economic and Social Affairs Population Division, United Nations New York, 2006, United Nation publication.
(7) "A recent study commissioned by the World Bank shows that modern patterns of city growth are increasingly land-intensive. Average urban densities (that is, the number of inhabitants per square kilometre of built-up area) have been declining for the past two centuries. As transportation continues to improve, the tendency is for cities to use up more and more land per person. The built-up area of cities with populations of 100,000 or more presently occupy a total of about 400,000 km2, half of it in the developing world. Cities in developing countries have many more people but occupy less space per inhabitant. In both developing and industrialized countries, the average density of cities has been declining quickly: at an annual rate of 1.7 per cent over the last decade in developing countries and 2.2 per cent in industrialized countries". Source: UNFPA, United Nations Population Fund. See: http://www.unfpa.org
(8) see the World Bank research Programme, 2005-2007 which highlight the dynamics of global urban expansion.
(9) Total emissions of carbon dioxide, excluding land-use, represents the mass of carbon dioxide (CO2) produced during the combustion of fossil fuels, as well as from gas flaring and the manufacture of cement.
Roughly 75% of global CO2 emissions are from the burning of fossil fuels and cement manufacturing. These emissions, together with CO2 from land-use changes and the emissions of five non-CO2 gases--methane (CH4), nitrous oxide (N2O), hydrofluorocarbons (HFCs), perfluorocarbons (PFCs), and sulfur hexafluoride (SF6)
constitute the main sources contributing to climate change. sources: the Carbon Dioxide Information Analysis Center (CDIAC), the International Energy Agency (IEA), and the Energy Information Administration (EIA).
(10) The twentieth century witnessed the rapid urbanization of the world's population. The global proportion of urban population increased from a mere 13 per cent in 1900 to 29 per cent in 1950 and, according to the 2005 Revision of World Urbanization Prospects, reached 49 per cent in 2005. Since the world is projected to continue to urbanize, 60 per cent of the global population is expected to live in cities by 2030. The rising numbers of urban dwellers give the best indication of the scale of these unprecedented trends: the urban population increased from 220 million in 1900 to 732 million in 1950, and is estimated to have reached 3.2 billion in 2005, thus more than quadrupling since 1950. According to the latest United Nations population projections, 4.9 billion people are expected to be urban dwellers in 2030. source:
http://www.un.org/esa/population/publications/WUP2005/2005wup.htm see also the urban agglomeration 2005 Wall Chart by Department of Economic and Social Affair, Population Division; and the UN-Habitat annual Report 2005: Responding to the challenges of an urbanizing world. Published by: United Nations Human Settlements Programme (UN-HABITAT)
(11) In the IEO 2009 reference case, world energy consumption increases from 472 quadrillion Btu in 2006 to 552 quadrillion Btu in 2015 and 678 quadrillion Btu in 2030Ña total increase of 44 percent over the projection period (Figure 10 and Table 1). Total world energy use in 2030 is about 2 percent lower than projected in the International Energy Outlook 2008 (IEO2008), largely as the result of a slower overall rate of economic growth in this year's reference case. The current economic downturn dampens world demand for energy in the near term, as manufacturing and consumer demand for goods and services slow. IEO2009 assumes, however, that most nations will begin to return to trend growth within the next 12 to 24 months. Source: US Energy information Administration . http://www.eia.doe.gov
(12) see: World Urbanization Prospects: The 2007 Revision Population DatabaseUrbanisation to see the differences between geographical areas. http://esa.un.org/unup/
(13) More than 90 percent of future population growth will be concentrated in cities in developing countries and a large percentage of this population will be in underdeveoped country. In Africa and Asia where urbanization is still considerably lower (40 percent), both are expected to be 54 percent urban by 2025 (UN 1995; 2002).
"One significant feature of the urbanization process in Africa is that, unlike Asia and Europe, much of the growth is taking place in the absence of significant industrial expansion. Although, Africa is fast urbanizing, mega-cities defined as cities with 10 million inhabitants or more are few" Panel Contribution to the PERN Cyberseminar on Urban Spatial Expansion by Kwasi Nsiah- Gyabaah, PERN Steering Committee member and Principal, Sunyani Polytechnic, Sunyani, BA, Ghana.
According with Un Habitat report by 2030, Asia and Africa will both have higher numbers of urban dwellers than any other major area of the world. Urban Agglomerations, or More Mega Cities. By 2015, it is expected that there will be 23 cities with a population over 10 million. Of the 23 cities expected to reach 10 million plus by 2015, 19 of them will be in developing countries.
(14) At the end of 2008, China's total population was 1.33 billion, with 723 million (54%) and 607 million (46%) residing in the rural and urban areas respectively (not including Hongkong, Macau, Taiwan). By 2025 China's urban population is expected to rise to 926 million from 572 million in 2005. By 2030 that number will increase to a billion. Source wikipedia
(15) "Since China started its economic reform in 1978, rural to urban migration became a particularly important social phenomenon. The principal reason for migration from primarily rural to urban areas is to seek non-agricultural work opportunities and escape poverty. By 2020, it is estimated that another 100 to 150 million"surplus"rural laborers will join the rural labor migration. From the National 1% population sampling survey in 2005, the number of rural migrant laborers reached 147 million, accounting for around 30 per cent of 490 million rural laborers of china".
(16) To hightlight the urbanisation in EU see at Urban sprawl; a European challenge by European Commission/Joint Research Centre. Copenhagen, 2006
(17) "Athens and Warsaw show population growth combined with increase in the sprawling process, Ljubljana, Stockholm and Vienna are experiencing growth in the urban area but with modest sprawling, Leipzig and Liverpool show the case of declining in the urban area linked with urban sprawling process. Source: URBS PANDENS calculations from the URBAN AUDIT data.
(18) the European cities between 1990- 2000 have become much less compact see picture 6.
(19) the growth of built-up areas in Europe reached its peak in 1950s-1960s, when the average annual growth rate reached 3.3 %. Between 1990-2000 the growth of urban areas increate to 5.4 %, consuming more than 8000 km2 equivalent to the entire territory of Luxembourg. Source EEA
(20) "Although the population is decreasing in many regions of Europe, urban areas are still growing in those areas, notably Spain, Portugal and some parts of Italy. Conversely, moderate increases of population accompanied by a large expansion of urban areas can be observed in Spain, Portugal, Ireland and the Netherlands. Major gains of population (> 10 %, through immigration) can only be observed in western Germany, where the average annual expansion of built-up areas is 47 000 ha/year, growth equivalent over 5 years to the area of Greater Copenhagen" Source: Urban sprawl; a European challenge by European Commission/Joint Research Centre. Copenhagen, 2006. Pag.11.
(21) Therefore, urban sprawl in Europe requires a different definition and theoretical explanations of causes and consequences from those developed to explain urban sprawl in North America. For these diferences see an interesting research work by Nata_a Pichler-Milanovic of the Oddelek za geografijo, Filozofska fakulteta Univerze v Ljubljani titled: "European urban Sprawl: Sustainability, Cultures of (anti)urbaniSm and ÈHybrid CitySCapES".
(22) In 2005 the EU population was around 455 million, an EU had a population density of about 117.5 inhabitants per km2. During the same year the USA, with a population of 296 million had a population density of about 31.6 inhabitants per km.
(23) Between them: J. Fang, L. Shenghe, Y. Hong, Z. Qin : "Measuring urban sprawl in Beijing with geo-spatial indices". Science Press, co-published with Springer-Verlag GmbH, Volume 17, Number 4 / October, 2007.
(24) The Urban Sprawl Exploratory Tool is available on www.casa.ucl.ac.uk/monitor and also from the SCATTER web site www.casa.ucl.ac.uk/scatter . "The Urban Sprawl Exploratory Tool (USET) is an interactive tool implemented on Internet. It is intended for local authorities and planning actors involved in decision making. Its objectives are to inform and raise awareness about issues related to urban sprawl and to explore (monitor) variables and indicator related to sprawl. The final objective is to provide some help in making a diagnosis about sprawl and building a strategy".
(25) See the map by U.S. Department of Energy data (DOE, 2001). This map illustrates per capita carbon emissions (in tons) at a country-level and copare it with the density. The highest per capita emissions are found in the U.S., followed by Canada, Australia, and Saudi Arabia. All this county has between the lowest residential density per km/q in the world.
(26) see the European Environment Agency website:
http://ims.eionet.europa.eu/Sectors_and_activities/transport/indicators for infrastructure investment EU by mode, 1990 to 1995, and shares in 1990 and 1995 of rail and road.
(27) see the European Envinronemt Agency website:
http://ims.eionet.europa.eu/Sectors_and_activities/transport/indicators
(28) "A recent survey has indicated that in New York city, per capita GHG emissions are among the lowest in the United States. This is because less energy is needed to heat, light, cool and fuel buildings in this densely populated city because houses are packed closer together and are below average in size". Nata_a Pichler-Milanovic
(29) see an article from www.eurozine.com by Krzysztof Pomian, titled "European identity: Historical fact and political problem" he investigates the root of the European identity.
(30) see Patacchini, E. Zenou, Y: Urban Sprawl in Europe. Wharton Papers 2009E-ISSN: 1533-4449.
(31) See F.Munoz "Lock living: Urban sprawl in Mediterranean cities" Department of Geography, Universitat Aut˜noma de Barcelona, Barcelona, Spain. For Mu–oz "Lock living" refers to the importance of security design, consumed as a commodity, in the new suburban residential landscapes of Mediterranean cities. "The sprawling displays dresses them up as private-urban-ecological-thematic paradises, as a residential landscape that becomes image more than territory and, in this sense, a commodity. This commodification process refers both to the residential space and the inhabitants' lifestyles as the domestic landscape, created by private security, clearly shows".
(32) The residential densities tends to fall at the north and west of Europe, inside it is generally higher at south. Actually the five urban areas with residential densities of at least 10.000 inhabitants/km2 are all located in southern or south-eastern Europe. Source EEA.
(33) The European Environment Agency (EEA) is an agency of the European Union. its task is to provide sound, independent information on the environment. It is a major information source for those involved in developing, adopting, implementing and evaluating environmental policy, and also the general public. Currently, the EEA has 32 member countries. EA's mandate is: to help the Community and member countries make informed decisions about improving the environment, integrating environmental considerations into economic policies and moving towards sustainability to coordinate the European environment information and observation network
(34) head of policy & public affairs, at the seminar co-hosted by the Urban-Housing Intergroup of the European Parliament and the Royal Institution of Chartered Surveyors (RICS) in Brussels (17 October 2007).
(35) Nata_a Pichler-Milanovic: EuropEan urban Sprawl: SuStainability, CulturES of (anti)urbaniSm and ÈHybrid CitySCapES. Nata_a Pichler-Milanovic is from Oddelek za geografijo, Filozofska fakulteta Univerze v Ljubljani, Slovenija
(36) Population density and Energy consumption, selected World cities. Source: Adopted from Newman, P. and Kenworthy, J., 1999. And Population density and CO2 emissions, selected European cities. Source: Adopted from Ambiente Italia, 2003.
(37) For the definition of "heat island" look at the U.S Environmental Protection Agency: http://www.epa.gov/hiri/
"heat Island describes built up areas that are hotter than nearby rural areas. The annual mean air temperature of a city with 1 million people or more can be 1.8-5.4¡F (1-3¡C) warmer than its surroundings. In the evening, the difference can be as high as 22¡F (12¡C). Heat islands can affect communities by increasing summertime peak energy demand, air conditioning costs, air pollution and greenhouse gas emissions, heat-related illness and mortality, and water quality".
(38) In order to focus on the relationship between "green buildings" and morphological assessment it is instructive to consider a US case study by Environmental Building News (2007): it examined the world's first LEEDTM Platinum building, the Chesapeake Bay Foundation's Philip Merrill Environmental Centre, which replaced an urban location with a suburban one. The study concluded that despite the greater efficiency of the building itself, "the additional energy use from more employees driving to work may well exceed the energy savings realized by the green building." Cited in Environmental Building News, 2007
(39) Norman, J.; MacLean, H. L.; Kennedy, C. A. Comparing High and Low Residential Density: Life-Cycle Analysis of Energy Use and Greenhouse Gas Emissions. J. Urban Plan. Dev.ÑASCE 2006, 132 (1), 10-21.
(40) Kenworthy. J "Transport Energy Use and Greenhouse Gases in Urban Passenger Transport Systems: A Study of 84 Global Cities".
(41) In accordance with EU research these savings represent 41% of a wedge. The no-sprawl and infill scenarios offer 53% and 60% of a wedge, respectively, compared with BAU, with no innovation.
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Revision of the official United Nations population estimates and projections. The picture show that most of the additional 2.3 billion people will enlarge the population of developing countries, which is projected to rise from 5.6 billion in 2009 to 7.9 billion in 2050, source: 2008 Revision of World Population Prospects Department of Economic and Social Affairs Population division, United Nation.
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The Statistics on Deforestation reveal countries with large net changes in forest 2000-2005. source United Nations Food and Agricultural Organization.
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Average annual per cent growth of urban population. 1990-2003. Population division, United Nation
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This map indicates global population density for 1995. Population density is shown to be highest in India, eastern China, and central Europe. Alternatively, low population density are shown in central South America, North Africa, Australia, western China, and western U.S. source WRI 2000 based on CIESINI 2000.
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Annual growth of build up areas from the mid -1950 to the late 1990s, selected European cities. Source Moland (JRC) and Kasanic. 2006.
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Low density residential areas as a proportion of all residential areas built after mid 1950s, selected European cities. Source Moland (JRC) and Kasanic. 2006.
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Population growth and the growth of built-up areas (mid 1950s to late 1990s), selected European cities. Source Moland (JRC) and Kasanic. 2006.
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Carbon Emissions from Energy Use and Cement Manufacturing, 1850 to 2000. WRI, 2003. Available on-line through the Climate Analysis Indicators Tool (CAIT). at http://cait.wri.org. Washington, DC: World Resources Institute.
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Population density and Energy consuption, selected world cities (on the left) source Adopted from Newman, P. and Kenworthy, j. 1999. On the right Population and CO2 emission, selected European cities. Source Adopted from Ambiente Italia, 2003.
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Comparison between selected European cities with low density (Oslo and Nantes) and high density (Barcelona and Brussels): Provate passante tran sport Energy use per person, 1995 (above); Urban density, 1995 (person/ha). Source EEA. UE.
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Comparison between selected European cities with low density (Oslo and Nantes) and high density (Barcelona and Brussels): Public transportation boardings per person, 1995 (above); ration of public transportation speed, 1995. Source EEA. UE.
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Comparison between selected European cities with low density (Oslo and Nantes) and high density (Barcelona and Brussels): Lenght of freeway per capita, 1995 (metres). Source EEA. UE.
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