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The Contribution of Cities to Global Warming and their Potential Contributions to Solutions David Satterthwaite

Environment and Urbanization ASIA 1(1) 1–12 © 2010 National Institute of Urban Affairs (NIUA) SAGE Publications Los Angeles, London, New Delhi, Singapore, Washington DC DOI: 10.1177/097542530900100102 http://eua.sagepub.com

Abstract Cities are often considered to be major causes of climate change (through being centres of carbon intensive production and consumption). But as this article explains, the proportion of greenhouse gas emissions that are generated in cities is usually over-stated. In addition, blaming cities misses the point that they can be potential solutions as places where high living standards are achieved with much lower levels of greenhouse gas emissions per person. It also misses the very low greenhouse gas emissions per person in most cities in lowincome nations and obscures the issue that it is not cities but high individual and household consumption that underpins most greenhouse gas emissions. The article ends by considering what can moderate, stop and reduce greenhouse gas emissions from two perspectives: where the emissions are produced; and where these are consumed. Keywords climate change, cities, consumption, greenhouse gas emissions, urbanization

Introduction The urgent need to cut global emissions of greenhouse gases to avoid dangerous climate change inevitably leads to discussions of where responsibility for cutting emissions lies. A convincing case can be made that most of the responsibility for cutting emissions lies with high-income nations, not only because they have much higher emissions per person now but also because of their much larger historic contribution to greenhouse gas emissions in the atmosphere. Most such nations also have low or no population growth and economies that have become less carbon intensive. Within low- and middle-income nations, there is a worry that controls on emissions will constrain their development and any such controls seem so unfair, especially for nations where per capita greenhouse gas emissions are one-tenth or even one-hundredth that of high-income nations. But the need to cut global emissions of greenhouse gases is so urgent that it will need commitments from low- and middle-income nations. This is especially the case for nations with rapidly expanding economies (which usually means rapidly growing greenhouse gas emissions) and for the large population nations (whose total emissions are high, even though they may have relatively low emissions per capita). The large population nations in Asia with successful economies (especially China and India) figure particularly prominently in such discussions, both because of their very substantial contribution to global emissions and because economic success is increasing greenhouse gas emissions within their borders. The reduction in global

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greenhouse gas emissions that is needed to avoid dangerous climate change needs the successful Asian economies to develop far less carbon intensive production systems and consumption patterns than those in highincome nations. Thus, the issue is how to arrive at global agreements between nations that produce the needed reduction in global emissions while not penalizing low- and middle-income nations. Cities have critical roles in this as potential problems (through being centres of carbon intensive production and consumption) and as potential solutions (through being places where high living standards/quality of life are achieved with much lower levels of greenhouse gas emissions per person).

Allocating responsibility for greenhouse gas emissions The greenhouse gas emissions that are driving climate change are generally allocated to nations. Inventories of greenhouse gas emissions within each nation lead to lists of nations, showing how they compare with other nations in total emissions or in emissions per person. So, for instance, in 2005, average per capita emissions for the most important greenhouse gases varied from less than 0.1 to over 25 tonnes of carbon dioxide equivalent;1 for the USA, the per capita figures was 23.5 tonnes, for China, 5.5 tonnes, for Indonesia, 2.7 tonnes, for India and the Philippines, 1.7 tonnes and for Bangladesh, 0.9 tonnes.2 Figure 1 illustrates the scale of the differentials in per capita greenhouse gas emissions between nations. Greenhouse gas emission inventories have also been calculated for some cities, as shown in Figure 2. Here too, the differentials in per capita emissions are very large—from Washington DC with close to 20 tonnes per person to Sao Paulo with 1.5 tonnes per person (Air Quality Division, 2005; The Municipal Secretariat of Green (issues) and of the Environment of São Paulo, 2005). If data were available for a wider range of urban centres, it is likely that most such centres in low-income nations would have much lower greenhouse gas emissions per person than Sao Paulo. However, some successful cities in middle-income nations may have emissions per person that are relatively high—for instance most of China’s largest cities (Dhakal, 2004, 2009). A study of 15 South African cities found that for 2004, average per capita emissions of carbon dioxide varied from 1.7 to 49.5 tonnes per person; for the largest cities, it varied between 4.7 and 8.3 tonnes per person while for two industrial cities the figure was over 40 tonnes per person (Sustainable Energy Africa, 2006). But these figures are misleading because it is not cities or nations that produce greenhouse gas emissions but particular human activities (that happen to be located within particular nations or particular urban or rural centres). There are also many ambiguities as to which emissions should be allocated to which localities. Should the greenhouse gas emissions generated by aircraft be assigned to the city or nation where the aircrafts are refuelled or the places where the passengers live? Should the greenhouse gas emissions from generating electricity in a coal, oil or gas fired power station be allocated to the location of the power station or the places where electricity is consumed? Should the greenhouse gas emissions that go into making (for instance) cars or fridges be allocated to the places they are produced or the places they are consumed? This has become a hot political issue since a significant part of the greenhouse gas emissions generated by nations with successful export industries are from these industries (Dhakal 2004). In negotiations between national governments of where responsibilities for cutting emissions lies, the nations with successful export industries will want these emissions assigned to the nations where these exports are consumed, not where they are produced.

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The Contribution of Cities to Global Warming

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Figure I. Average Per Capita Emissions of Greenhouse Gases; Selected Nations, 2005 Source: CAIT (2009). Note: These figures include not only CO2 but also the other greenhouse gases included in the Kyoto Protocol (methane, nitrous oxide, sulphur hexafluoride, hydrofluorocarbons and perfluorocarbons). Their contributions to global warming are converted into CO2e. However, they do not include emissions from land use changes.


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Figure 2. Comparing Cities and their Nations for Greenhouse Gas Emissions Per Person Source: Dodman (2009).

Ultimately, the root cause of almost all human-induced greenhouse gas emissions is the consumption of goods and services. This implies that responsibility for such emissions should be allocated to individual consumers, not to nations or cities. A wealthy person with a high-consumption lifestyle will generate thousands of times more greenhouse gas emissions during their life than, say, slum dwellers or pavement dwellers in Mumbai. So a just system of allocating responsibility for reducing green house gas emissions would focus on those with high-consumption lifestyles. But it is difficult to produce the measurement systems to allocate greenhouse gases to consumption, although work is underway to do so (see Hertwich and Peters, 2009). At present, greenhouse gas emission inventories are made for nations or for cities, based on what is produced within their boundaries. And even if it is consumption choices by middle and upper income groups that drive global warming, it is valuable to learn where in the production of goods and services there are high greenhouse gas emissions and thus where it is possible to reduce the greenhouse gas emission intensity of such production. Environment and Urbanization ASIA, 1, 1 (2010): 1–12 Downloaded from eua.sagepub.com at SAGE Publications on December 6, 2012


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What proportion of greenhouse gases are emitted by cities? Cities are usually portrayed as problems in relation to climate change. The Clinton Climate Initiative has long claimed that cities produce 80 per cent of the world’s greenhouse gas emissions and this is a figure that has become widely cited. But according to our calculations, drawing on the most recent figures from Intergovernmental Panel on Climate Change (IPCC), cities produce between 30 and 40 per cent—see Table 1. To claim that 80 per cent of emissions come from cities is always a puzzling statistic when 30 per cent of emissions come from agriculture and deforestation (almost all of which is outside cities). So perhaps cities account for all other emissions and so contribute to 70 per cent of total emissions. But this cannot be correct as there are all the other sources of emissions that are not in cities but in rural areas or in urban centres too small to be considered cities—including many coal, oil and gas fired power stations, many heavy industries and a considerable percentage of wealthy, high consumption households. In high-income nations, a large part of the wealthy population does not live in cities (although their income earners may commute to cities). Most large power stations and most heavy industries are also outside cities. This helps explain why several city studies have shown that average per capita emissions are lower in that city when compared to national averages—see Figure 2.

Confusions and limitations in the data The high estimates for the role of cities in global greenhouse gas emissions may be confusing fossil fuel burning with greenhouse gas emissions. IPCC figures for 2004 suggest that carbon dioxide from fossil fuel use accounted for 57 per cent of global anthropogenic greenhouse gas emissions. So cities may have 70 per cent of fossil fuel combustion within their boundaries but this would mean around 40 per cent of all greenhouse gas emissions. The figures that overstate the role of cities in global emissions may be making false assumptions. For instance, they may be assuming that all industries and power stations are in cities. Or they may be muddling up ‘cities’ with ‘urban centres’ (a considerable part of the world’s urban population live in urban centres too small to be considered cities). But it is not cities in general but particular cities where there are high per capita emissions. Most cities in Africa, Asia and Latin America are likely to have relatively low emission-levels per person; most cities in the poorest nations are likely to have between a twentieth and a hundredth of the emissions per person of (say) New York or London. However, the figures for China’s large cities and for South Africa’s large cities and some industrial cities suggest that there are many exceptions—perhaps especially industrial cities and increasingly prosperous cities where electricity provision is from coal-fired power stations.

From production-based to consumption-based analyses If we choose to allocate greenhouse gas emissions not to the nation or city (or small town or rural area) where they are produced but to the people whose consumption led to these emissions, it changes the picture (see Table 2). Here, emissions from, say, a steel plant are not allocated to the place where the plant is located but Environment and Urbanization ASIA, 1, 1 (2010): 1–12 Downloaded from eua.sagepub.com at SAGE Publications on December 6, 2012

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17.4 13.5 13.1

7.9

2.8

Forestry

Agriculture

Transport

Residential and commercial buildings

Waste and wastewater Total

Source: Satterthwaite, 2008.

100

19.4

25.9

Industry

Energy supply

Sector

Percentage of Greenhouse Gas Emissions (2004) A large part of this is from fossil fuel power stations and a high proportion of fossil fuel power stations are not in cities. A guess of one-third to one-half of energy supply greenhouse gas emissions from city-based power stations? A large proportion of heavy industry (which accounts for most greenhouse gas emissions from industry) is not located in cities, including many cement factories, oil refineries, pulp and paper mills, metal smelters… A guess of two-fifths to three-fifths of industry greenhouse gas emissions in cities? This is from rural land use and land use changes including deforestation; none assigned to cities. Some large cities have considerable agricultural output but mostly because of extended boundaries encompassing rural areas. None assigned to cities. Impossible to say how much to assign to cities. Private use of automobiles in highincome nations a large part of this, but much car use in these nations is by rural dwellers and small urban centre dwellers. Guess that 60–70 per cent of transport greenhouse gas emissions assigned to cities. Difficult to know how to assign this between cities, small urban centres and rural areas. Large sections of middle- and upper-income groups in high-income nations do not live in cities—and a significant and increasing proportion of commercial buildings are located outside cities. 60–70 per cent of greenhouse gas emissions from this assigned to cities. More than half of this is landfill methane, but a proportion of this would be outside city boundaries.

What Proportion are Generated within Cities

Table 1. What Proportion of Global Anthropogenic Greenhouse Gas Emissions Should be Allocated to Cities

30.5–40.8

1.5

4.7–5.5

7.9–9.2

7.8–11.6

8.6–13.0

Percentage Allocated to Cities


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Table 2. Possible Drivers of Growing Greenhouse Gas Emissions in a City or a Nation’s Urban Population and What Can Moderate, Stop or Reduce this Growth Sector

What Drives Growing Greenhouse Gas Emissions in Urban Areas?

What can Moderate, Stop or Reduce this Growth?

From the perspective of where the greenhouse gas emissions are produced Energy supply

A large part of this is growing electricity production from fossil fuel power stations; many large fossil fuel power stations are located outside urban areas but the greenhouse gas emissions from the electricity used in urban areas are usually allocated to these urban areas (see below).

A shift to less greenhouse gas-emitting power generation and distribution; incorporation of electricity-saving devices; an increase in the proportion of electricity generated from renewable energy sources and its integration into the grid. Carbon capture can be applied to fossil-fuelled power stations which can considerably reduce their emissions although the costs and the level of emission reduction are uncertain, as are the costs relative to other measures. Industry Growing levels of production; growing A shift away from heavy industries and energy intensity in what is produced; from industry to services; increasing energy importance of industries producing goods efficiency within enterprises; capture of whose fabrication entails large greenhouse particular greenhouse gas emissions from gas emissions—for example, motor waste streams. vehicles. Forestry and agriculture Many urban centres have considerable agricultural output and/or forested areas, but mostly because of extended boundaries that encompass rural areas; from the production perspective, greenhouse gas emissions generated by deforestation and agriculture are assigned to rural areas. Transport Growing use of private automobiles; Increasing the number of trips made on foot, increases in average fuel consumption of by bicycle, on public transport; a decrease private automobiles; increased air travel in the use of private automobiles and/or a (although this may not be allocated to decrease in their average fuel consumption urban areas). (including the use of automobiles using alternative fuels); ensuring that urban expansion avoids high levels of private automobile dependence. Residential/commercial Growth in the use of fossil fuels and/or Cutting fossil fuel/electricity use, thus cutting buildings growth in electricity use from fossil fuels greenhouse gas emissions from space heating for space heating and/or cooling, lighting (usually the largest user of fossil fuels in and domestic appliances. temperate climates) and lighting; much of this is relatively easy and has rapid paybacks. (Table 2 continued )


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(Table 2 continued ) Sector Waste and wastewater



Growing volumes of solid and liquid wastes Reducing volumes of wastes, and waste and of more energy intensive waste. management that captures greenhouse gas emissions (waste dumps being important sources of methane emissions).

From a consumption perspective Energy supply Greenhouse gas emissions from energy supply now assigned to consumers of energy supplies and electricity, so emissions growth is driven by increasing energy use; consumers are also allocated the emissions from the energy used to make and deliver the goods and services they consume. Industry Greenhouse gas emissions from industries and from producing the material inputs they draw on no longer allocated to the enterprises that produce them, but rather to the final consumers of the products, so again emissions growth is driven by increased consumption. Forestry and agriculture Greenhouse gas emissions from these no longer allocated to rural areas (where they are produced), but rather to the consumers of their products (many or most in urban areas); note how energy intensive much commercial agriculture has become; also the high emissions implications for preferred diets among higher-income groups (including imported goods, high meat consumption…). Transport As in the production perspective; greenhouse gas emissions from fuel use by people travelling outside the urban area they live in are allocated to them, so this includes air travel; also concern for emissions arising from investment in transport infrastructure.

As in the production perspective but also a greater focus on less consumption among high consumption households; a shift to less greenhouse gas intensive consumption.

As in the production perspective but with an extra concern to reduce the greenhouse gas emissions embedded in goods consumed by residents and to discourage consumption with high emissions implications.

Encouraging less fossil fuel intensive production and supply chains for food and forestry products; addressing the very substantial non-CO2 greenhouse gas emissions from farming (including livestock); forestry and land use management practices that contribute to reducing global warming.

As in the production perspective but with a stronger focus on reducing air travel and a concern for lowering the greenhouse gas emissions implications of investments in transport infrastructure (which is often very energy-intensive). (Table 2 continued )



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(Table 2 continued ) Sector Residential/commercial buildings

Waste and wastewater

Public sector and governance



As in the production perspective, but with the addition of greenhouse gas emissions arising from construction and building maintenance (including the materials used to do so). Large and often growing volumes of solid and liquid wastes; the greenhouse gas emissions embedded in the materials before they became wastes and the emissions that waste disposal generates are allocated to the consumers who generated the waste, not to the waste or waste dump. Conventional focus of urban governments on attracting new investment, allowing urban sprawl and heavy investment in roads, with little concern for promoting energy efficiency and low greenhouse gas emissions.

As in the production perspective but with an added interest in reducing the carbon dioxide emissions caused by the production of building materials, fixtures and fittings. As in the production perspective but with a new concern to reduce waste flows that arise from consumption in the city but contribute to greenhouse gas emissions outside its boundaries.

Governance that encourages and supports all the above; also a strong focus on lowering greenhouse gas emissions through better management of government-owned buildings and public infrastructure and services; includes a concern for reducing emissions generated in the building of infrastructure and the delivery of services.

Source: Developed from Table 1 in Satterthwaite (2009).

to the home of the person who buys and uses the goods into which the steel went. Using this kind of accounting system would mean wealthy cities such as London, New York or Tokyo suddenly have much higher emissions per person because most of the goods consumed by their inhabitants are made elsewhere. The big manufacturing cities in Asia and Latin America would have lower levels of emissions because a significant part of their greenhouse gas emissions are from their industries and these would now be allocated to the places where those who bought these goods live. Greenhouse gas emissions from travel get allocated to the person who does the travelling. Emissions from agriculture and deforestation also get allocated to the persons who consumed the food or forest products. Under this kind of scheme, cities may account for 60 or more per cent of all greenhouse gas emissions—although this is a bit misleading because most of these emissions are from a relatively small proportion of the world’s cities—the most prosperous ones with the most inhabitants with high-consumption lifestyles. So here too, it is not cities in general but a small proportion of cities that account for most greenhouse gas emissions. However, even here, a very large part of the consumption-driven emissions would come from wealthy households living outside cities—in urban centres too small to be considered cities and in rural areas. Generally, a wealthy rural household will have higher greenhouse gas emissions than a comparably wealthy


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city-based household because of greater private automobile use and generally larger heating and cooling demands from their homes. This consumption-based accounting for greenhouse gas emissions would also produce even larger differentials between cities in per capita emissions. Cities that concentrate wealthy people with high-consumption lifestyles would probably have greenhouse gas emissions per person that were thousands of times larger than many small urban centres in low-income nations where there is little or no energy-intensive production and consumption levels are very low.

Intra-city rather than inter-city differentials Consumption-based accounting for greenhouse gas emissions also highlights the very large differentials within cities. The world’s richest high-consumption individuals are contributing hundreds and thousands of times more to global warming than many of the poorest individuals. In part, this is because the contribution of a large proportion of the poorest people is close to zero. For some it will be ‘less than zero’ as what they consume is so small and with very low carbon dioxide emissions while their work helps reduce carbon emissions—for instance, the millions of low-income households who make a living from reclaiming material from wastes for recycling or reuse. For any individual to contribute to global warming, they have to consume goods and services that generate greenhouse gas emissions. Perhaps as many as 1.2 billion rural and urban dwellers worldwide have such low consumption levels that they contribute almost nothing to climate change. Their use of fossil fuels is very low (most of them use woodfuel, charcoal or dung for fuels) and they have no electricity. Most of these 1.2 billion ‘very low-carbon’ people will use transport that produce no carbon dioxide emissions (walking, bicycling) or low emissions (buses, mini-buses and trains, mostly used to more than full capacity; for more details, see Satterthwaite, 2009). This is why it is incorrect to suggest that it is the increase in the world’s population that drives the growth in greenhouse gas emissions. This cannot be so, when the lifetime contribution to such emissions of a person added to the world’s population varies by a factor of more than 1,000 depending on the circumstances into which they are borne and their life possibilities and choices. It is the growth in the number of consumers and the greenhouse gas implications of their consumption patterns that are driving climate change.

Do we see cities as problems or solutions? One justification for emphasizing the very large role of cities in greenhouse gas emissions (including greatly over-stating it) is to get more attention to cities. This is much needed, given how little attention has been given to the role of cities in economic and social development. But overstating cities’ contribution to greenhouse gas emissions diverts attention from the real problem—the high-consumption lifestyles and life-choices of a relatively small proportion of the world’s population (most but not all of whom live in high-income nations). And focusing on cities in low- and middle-income nations as large greenhouse gas emitters (when most are not large emitters) produces the wrong agenda for change. It produces a focus on mitigation (greenhouse gas emission reduction) when what is urgently needed is a focus on adaptation (building resilience to



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the local impacts of climate change). Most of the cities most at risk from the impacts of global warming are in low- and middle-income nations, and it is generally among their low-income populations that risks are concentrated (Bartlett, 2008; Bicknell, Dodman and Satterthwaite, 2009). Most of these are cities that contribute very little to climate change but whose populations are far more at risk from climate change. What is so urgently needed for cities (and other urban centres and rural areas) is a focus on adaptation, including getting the protective infrastructure in place so their populations are not seriously impacted by climate change—as in, for instance, more or more intense extreme weather, sea level rise or constraints on fresh water supplies. But perhaps worse than this, blaming cities for most greenhouse gas emissions misses the point that wellplanned and governed cities are central to reducing emissions by delinking a high quality of life from high levels of consumption. This can be seen in part in the very large differentials between wealthy cities in gasoline use per person; most US cities have three to five times the gasoline use per person of most European cities (Newman and Kenworthy, 1989; Newman, 1996)—and it is difficult to see that Detroit has five times the quality of life of Copenhagen or Amsterdam. Many of the most desirable (and expensive) residential areas in the world’s wealthiest cities have high densities and building forms that can minimize the need for space heating and cooling—much more so than housing in suburban or rural areas. Most European cities have high-density centres where walking and bicycling are preferred by much of the population, especially where good provision is made for pedestrians and bicyclists. Many European cities also have high-quality public transport that keeps down private automobile ownership and use. Here automobile ownership and use can be low, even among prosperous households. Cities also concentrate so much of what contributes to a very high quality of life that need not imply high material consumption levels (and thus high greenhouse gas emissions)—theatre, music, museums, libraries, the visual arts, dance and the enjoyment of historic buildings and districts. Cities have also long been places of social, economic and political innovation; indeed, in high-income nations, city politicians often demonstrate a greater commitment to greenhouse gas reduction than do national politicians. Achieving the needed reduction in global greenhouse gas emissions depends on seeing this potential of cities to combine high quality of life with low greenhouse gas emissions and acting on it. Table 2 describes the most likely sources of growing greenhouse gas emissions for any city or any nation’s urban population from both the production perspective (based mainly on where the greenhouse gas emissions are produced) and the consumption perspective. These are discussed, using the sectors in the IPCC’s 2007 Assessment (Metz, Davidson, Bosch, Dave and Meyer [IPCC], 2008), but with the addition of ‘public sector and governance’ within the consumption perspective (see also, Hertwich and Peters, 2009). It also notes the factors that can moderate, stop or reduce greenhouse gas emissions. Notes 1. CO2e (carbon dioxide equivalent emission) is a measure of emissions where other greenhouse gases (such as methane) have been added to carbon dioxide emissions, with adjustments made for the differences in their global warming potential for a given time horizon. 2. CAIT (2009). These figures do not include greenhouse gas emissions from land-use changes since these are not available for 2005. Land use changes are a significant contributor to climate change and for low and middle income nations with rapid deforestation, these can be a significant contributor to their total greenhouse gas emissions.


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References Air Quality Division. 2005. District of Columbia greenhouse gas emissions inventories and preliminary projections. Washington DC: District of Columbia Department of Health. Bartlett, Sheridan. 2008. Climate change and urban children: Implications for adaptation in low and middle income countries, IIED Working Paper. London: IIED. Bicknell, Jane, Dodman, David and Satterthwaite, David (eds). 2009. Adapting cities to climate change: Understanding and addressing the development challenges. London: Earthscan Publications. CAIT. 2009. Climate Analysis Indicators Tool Version 6.0, World Resources Institute. Washington DC, Retrieved 15 October 2009 from http://cait.wri.org/cait.php. Dhakal, Shobhakar. 2004. Urban energy use and greenhouse gas emissions in Asian cities: Policies for a sustainable future. Kitakyushu: Institute for Global Environmental Strategies (IGES). ———. 2009. Urban energy use and carbon emissions from cities in China and policy implications. Paper presented at the Urban Research Symposium 2009 in Marseille and to be published in the Symposium Proceedings. Dodman, D. 2009. Blaming cities for climate change? An analysis of urban greenhouse gas emissions inventories. Environment and Urbanization, 21(1), 185–202. Hertwich, Edgar G. and Glen P. Peters. 2009. Carbon footprint of nations: A global trade-linked analysis. Environmental Science and Technology, August, http://pubs.acs.org/doi/abs/10.1021/es803496a. Metz, B., Davidson, O.R., Bosch, P.R., Dave, R. and L.A. Meyer (IPCC). 2008. Climate change 2007: Mitigation— contribution of working group III to the fourth assessment report of the intergovernmental panel on climate change. Cambridge: Cambridge University Press. Newman, Peter and Kenworthy, Jeffrey. 1989. Cities and automobile dependence: An international sourcebook. Gower: Aldershot. Newman, Peter. 1996. Reducing automobile dependence, Environment and Urbanization, 8(1), 67–92. Satterthwaite, David. 2008. Cities’ contribution to global warming: Notes on the allocation of greenhouse gas emissions. Environment and Urbanization, 20(2): 539–49. ———. 2009. The implications of population growth and urbanization for climate change. Environment and Urbanization, 21(2): 545–67. Sustainable Energy Africa. 2006. State of energy in South African cities 2006; Setting a baseline. Westlake: Sustainable Energy Africa. Technical Summary of the IPCC Working Group III Report. In Metz B., Davidson, O.R., Bosch, P.R., Dave, R., and Meyer, L.A. (eds), Climate change 2007: Mitigation—contribution of working group III to the fourth assessment report of the Intergovernmental Panel on Climate Change. Cambridge, United Kingdom and New York, NY, USA: Cambridge University Press. The Municipal Secretariat of Green (issues) and of the Environment of São Paulo. 2005. Inventory of greenhouse gas emissions of the municipality of São Paulo, Centre of Integrated Studies on Environment and Climate Change, PostGraduate Engineering Programme Coordination of the Federal University of Rio de Janeiro.

David Satterthwaite is a Senior Fellow at the International Institute for Environment and Development (IIED) and editor of the international journal Environment and Urbanization. E-mail: david.satterthwaite@ iied.org
