This Research Bulletin has been published in B. Derudder, M. Hoyler, P.J. Taylor and F. Witlox (eds) (2012) International Handbook of Globalization and World Cities Cheltenham, UK, Northampton, MA, USA: Edward Elgar, pp. 318-327.
Please refer to the published version when quoting the paper.
This paper revisits the key themes addressed by Blowers and Pain in their contribution to the Open University's (1999) Understanding Cities book series - ‘The Unsustainable City?' The intention of their paper, which was written for the final volume of the series, subtitled ‘Unruly Cities?', was to provide a ‘turn of the twenty first century' overview of major governance challenges posed for the sustainability of the world's largest cities from a specifically geographical and spatial perspective. At a time when discourse on the relationship between sustainability, development and cities was dominated by positivist approaches, the authors' analysis focused on the growing significance of the relational and social nature of cities as key determinants of sustainability. But, in spite of the upsurge of interest and policy rhetoric on this critically important subject during the past decade, inter-city relations, as discussed by Blowers and Pain, still generally lack attention in the growing multidisciplinary literature.
Empirical research undertaken by the Globalization and World Cities (GaWC) research group in the intervening period indicates that the need to adopt a relational approach to understanding cities, and the juxtaposition between their development and sustainability, has become more necessary than ever. Thus the case for contextualizing debate through engagement with the increasingly complex relations of cities in contemporary ‘globalization' is revisited in the present paper. Whereas it is customary to begin the discussion of cities and sustainability by defining the term sustainable development, here I deliberately come to this later. Instead I begin by considering recent empirical evidence and theorization of changes affecting cities worldwide. This is because sustainability and development are relative and contested concepts which cannot be defined independently of cities.
Cities in transition – Mega-Cities, World Cities
The beginning of the twenty first century has marked a key transition in world development. In 2008, 3.3 billion people (more than half the global population) became an urban population (UNFPA 2007). A total of 58 cities in the world are expected to have a population size over five million by 2015 (Liotta 2009). Not only do United Nations forecasts indicate that five billion people (two-thirds of the global population) will be urban by 2030 (UNFPA 2007) but the most dramatic year-on-year increase in urbanization involves some of the world's poorest cities. While major migrations are not a new phenomenon, what is new is that very large cities have become the dominant focii of migration in the late C20th. This spatial reorganization is tailing off in ‘developed' countries but is ongoing in ‘developing' countries. Recent estimates indicate that world urban population will double to 2050 and in Africa it will increase from 40-60% (UNDP 2009, p.32).
Very large cities with a population over 10 million have generally been described as ‘mega-cities' in the policy and academic literature (see for example Perlman and O'Sheehan 2007) but cities of this size actually include different kinds of cities. Their estimated size is dependent on how the boundaries of a metropolitan area are defined, which is a matter of academic debate (see Hall and Pain 2006), and their social, economic, political and spatial constitution differs considerably. Developed world cities such as New York, London and Tokyo are widely referred to as mega-cities alongside cities in the developing world such as Guangzhou, Mexico City and Mumbai. But these examples illustrate very different development processes occurring in different cities, and different reasons for population growth including natural increase. In the developing world, a present cause of urbanization remains major intra-state, rural-urban migration, whereas in the developed world, the causes are more diverse but often include transnational migration (UNDP 2009). In both cases however, cities are now the present focii of production and employment which are socially essential, and this is the principal driver of ongoing urbanization. As Tacoli, et al. have emphasized,
“Attempts to limit urban growth by controlling migration are misguided - in part because migration flows are logical responses to changing economic opportunities and in part because most urban population growth is actually from natural increase, not net rural-to-urban migration.” (2008, p.50).
The spatial re-organization of human habitation into cities is taking place alongside the technological, informational and communications revolution which began in the late twentieth century, commonly referred to as globalization (Cochrane and Pain 2000). In the late twentieth century, this gave developed ‘world cities' (Friedman1986) a critical role as the source of people, knowledge and talent required to support the development of the modern ‘world economy'. The concentration of intelligence-based, creative resources and the capacity for innovation and economic growth in such cities has made them central to the functioning of the economies of states and wider political regions, for example the European Union. Importantly, they are the world locations for post-Fordist specialized knowledge-intensive sectors of the new tertiary economy known as advanced producer services, such as finance, law, accountancy etc, which are now key articulators of the world economy but cluster in ‘global city' service centres (Sassen 1991). They continue to draw in talent from around the world but have come to have a critically important role in adding value to primary and secondary sector economic activities in world-wide global production networks (Pain 2010). The ongoing importance of human interaction and clustering of complementary skills is still driving the transnational migration of skilled and professional labour to these cities, aided by reduced travel and communication costs (UNDP 2009 p.27, p.33).
In general, migration to large cities is driven by income inequalities within and between countries, the divergence between developing and developed world regions and the divergence between world, or global, cities and mega-cities. However the Pacific Asia region, especially China, is the recent exception to a longstanding geography of regional/city divergence with national per capita income increasing from 3-14 per cent of the developed country average between 1960 and 2007 (UNDP 2009, p.33). Although there are no accurate official statistics, intra-national and intra-regional migration are still an important feature in the developing world, including in China, because cities are the location of work which can dramatically improve livelihoods. As a recent United Nations report states, “ no country in the industrial age has ever achieved significant economic growth without urbanization. Cities concentrate poverty, but they also represent the best hope of escaping it.” (UNFPA 2007, p.1), however migrations are frequently constrained for the poor and unskilled by policy and economic barriers (UNDP 2009, p. 46). Contrary to cities operating within a neo-liberal framework, China has raised a major swathe of its population out of poverty by introducing its ‘open door' strategy and this is being articulated through major rural-urban population migration into vast mega-cities (Lo and Yeung 1998, Lin 2005).
Despite his dystopic (1998) mega-city vision, Manuel Castells has also identified the connectivity of all cities to value-adding advanced producer services networks as crucial for the economic survival and livelihood of the world population (Castells 2007) but for many cities this has not been achieved thus far. Mushrooming mega-cities in less economically developed world regions (termed ‘peripheral' in world systems theory and late twentieth century development studies) can be considered world cities which are disconnected from these key networks which are channels for global economic growth. Whilst historic uneven geographies of world economic development may be expected to be replicated in present divergences between cities, new empirical evidence indicates that they are in fact changing and this sheds light on recent developments in China.
Quantitative analysis of global advanced producer service networks between the years 2000 and 2008 by the Globalization and World Cities (GaWC) Research Network, shows a remarkable shift in the connectivity of Chinese cities. There has been a dramatic increase in global service network connectivity for cities in Pacific Asia, and in particular Chinese cities. Economic liberalization and powerful state intervention in China have quite deliberately reversed a previous policy of de-urbanization. The development of major cities Shanghai, Beijing and Guangzhou, since the Blowers and Pain 1999 paper has effectively connected China to the capitalist world economy leading to major economic expansion in just one decade (Lin 2000, Yeh 2005, Pain 2010). The analysis also shows that other cities in many places around the world are upgrading their ‘World City Network' connectivity (Taylor 2004, Derudder et al. 2009) indicating a significant shift in world city relations. This is not to say that disconnection can be eradicated easily - disconnection remains in fragmented and spatially specific locales in all cities, regardless of their overall economic development, as theorized in Manuel Castells' ‘Fourth World' (1998). However, the latest empirical evidence on global service network organization supports Allen Scott's tentatively optimistic vision of a change in established economic relations by which ‘core' capitalist countries have so far maintained their global dominance through their world cities. The global servicing role of world cities appears to be mobile in evolving business network structures (Pain 2010).
Conceptualizing city development as a process
There are two main conclusions from the assessment of how cities are changing at the start of the twenty first century. First, cities are becoming increasingly important as global social and economic interactional entities (the places where most people will in future live and work). Second two different development processes are happening in cities worldwide – here termed a global city process and a mega-city process. These two processes can both be present in the same time and space but, overall, more cities are becoming more ‘well-connected' in the global service economy - China's global connectivity spurt is exceptional. I turn next to consider how the conceptualization of cities can inform the distinction between these two development processes.
As the present era of global technological, economic and urban restructuring started to be felt in developed Western countries, Ray Pahl made a criticism of Peter Hall's 1986 JR James Memorial Lecture ‘From the unsocial to the social city' that (in spite of its title) its analysis mistakenly rested on economic theories and “not enough social theory” (Pahl 1986, p.10). As a long line of urban theorists had previously insisted, cities are primarily socially constituted and it still proves vitally important not to forget this. Urban sociologists in the US urban ecology ‘Chicago School' emphasized the importance of both the ‘social' and the ‘political' in the construction of cities long before contemporary globalization was envisaged. In ‘What is a City?', Lewis Mumford (1937, pp.184-188) emphasized the social interrelations between the ‘economic' and ‘ecological' dimensions of cities: The city is the “point of maximum concentration for the … form and symbol of an integrated social relationship, … a product of the earth... [and a] social division of labour, which serves not merely the economic life but the cultural process”. At a time when 1960's and 70's urban geography and planning was focusing on the classification of urban development based on locational analysis (for example in ‘Central Place Theory'), Jane Jacobs developed this reasoning, interpreting cities as the sites of social reproduction, diversified divisions of labour and complexity which create economic expansion and stimulate new work (Jacobs 1969, Taylor 2007). Thus city development is in practice structured both by social and economic reproduction.
As discussed by Peter Taylor, this complexity and consequent ‘new work' attaches to ‘cities' as opposed to smaller urban formations, ie ‘towns'. However, Jacobs' insights suggest that large urban populations do not always give rise to city economic vibrancy and expansion. The reason relates to the constitution of cities, hence city economies, as inherently the expression and outcome of social relationships. Thus in 1970 Henri Lefebvre discussed ‘urbanism' as a ‘social practice' and, together with David Harvey, linked the notion of the ‘production of urban space', its political organization and uneven geographies, to social practices (Lefebvre 1991, Harvey 1973). This line of argument underpinned Manual Castells' later (1996) conceptualization of cities in the globalizing ‘informational' and ‘network society' as a process which has been stimulated by, and also stimulates, technological innovation and constructs business connectivity and flows between cities world-wide, analyzed empirically by GaWC (Taylor 2004).
GaWC qualitative research on the global strategies and practices of advanced producer service networks suggests that without connectivity to the flows conveyed by them, mega-cities (which are the location of the world's poorest expanding population) are unsustainable socially, politically and environmentally (Lachman 1997, Castells 2007, Segbers 2007) and there are implications for the sustainability of smaller cities too, even in the Western world where structural adjustment is needed (Taylor and Aranya 2006). Specialized, knowledge-intensive work or ‘net-work' (Taylor 2007, Taylor and Pain 2007) which is conducted through cities by network forms of business organization, is now generally recognized as critical to support wider regional and national economies in the developed as well as the developing world (Pain 2008). Although inequalities persist between high paid/specialized and low paid /non-specialized service skills and pay, employment is shown to be fundamentally important to inter-generational progress towards greater economic and social equity (Perlman and O'Sheehan 2007). Services create a city environment that is conducive to beneficial flows of knowledge and finance between globalizing cities and to innovation and in investment in less environmentally damaging city infrastructures (Knox and Pain 2010). They also mark a transition from labour intensive and environmentally detrimental forms of employment, to ‘cleaner, hi-tech' economic production.
The degree of relative connection/disconnection from global service networks can thus be understood as defining the different development processes of global and mega-cities. Although Manuel Castells' attention to the Fourth World (1998) must not be overlooked, t he astonishing upward economic trajectory of liberalizing Chinese cities in less than ten years and the upgrading of global service connectivity in far more cities elsewhere, is indicative of a major world city restructuring process which seems to herald a new manifestation of development which Allen Scott has referred to as a “new social grammar of space” (Scott 2001, p.814), raising again his question posed in 2001, whether this can override “in important ways the spatial structure of core-periphery relationships that has hitherto characterized much of the macro-geography of capitalist development” (2001 p.817). Based on the recent insights into the contemporary global city development process from empirical analyses, how should this inform consideration of the sustainability of very large cities?
Sustainable development as political strategy
The concept of ‘sustainable development' remains value-laden and contested as discussed by Blowers and Pain (1999). ‘Sustainability' is a generalized and normative goal which can refer to almost anything (Mitlin and Satterthwaite 1996) hence sustainable development can be a means of achieving many different things. Following the work of the 1987 Brundtland Commission (WCED), Blowers and Pain interpreted the goal of sustainability as needing to include cities as a social outcome as well as productive of economic and bio-physical environmental and eco-sphere impacts in their analysis. They interpreted the dominant neo-liberal world economic strategy as reinforcing spatial inequities, thus they saw sustainable development as an oxymoron. They identified the tensions between Chinese urbanization and wider global environmental issues, but the dramatic rise in the global service economy connectivity of its mega-cities and their economic and social implications were then unanticipated. Viewing ‘development' as a potentially non-spatially dualistic process, albeit tempered and shaped by political and governance strategies for cities, brings to the fore interesting questions about the prospects for more sustainable patterns of development.
In 1999, the ‘green' agenda had only recently moved from its representation as a fringe, radical interest (for example Meadows et al. 1972, Devall and Sessions 1985) to a mainstream international policy issue. The urban and environmental justice movements were generally associated with radical political activism (Harvey 1973, 1996) and urban-rural/city-nature dualisms (Tuan 1978) were only beginning to be challenged by new relational discourses (for example Macnaughten and Urry 1998, Castree 2000, Swyngedouw and Kaika 2002, Kaika 2005, Heynen et al. 2006). Thus Blowers and Pain emphasized the need for a co-evolutionary approach to the relationship between sustainability and cities in which social development must be considered alongside anthropogenic environmental impacts. Since then, widespread publicity and the scientization and popularization of environmental debate (Hinchliffe and Woodward 2000, Cochrane and Pain 2000) has turned widespread attention towards biocentric ‘deep ecology' concerns (Johnston et al. 2002). Attempts to quantify and model environmental risk have gained prominent media attention. Social concerns and risks which relate to cities, such as poverty, malnutrition, disease, war and urban environmental degradation gain less attention. This tilting of the global debate begun at Brundtland, has implications for green, as well as human, ecological priorities since the former cannot be realized in isolation from the latter in an increasingly urban world.
Institutional approaches to conflicting international priorities remain subject to competing scientific and political claims and debate, and are in consequence often misguided and/or contradictory. Whilst policy is framed by an international institutional context, this is constituted by government, NGO and commercial interests that reflect powerful territorial, political and stakeholder interests. For all these reasons policy agendas have tended to veer away from sensitive and conflictual social and economic issues and towards less contentious environmental issues including bio-diversity and climate change. As in 1999, less palatable yet fundamental underlying issues concerning spatialities of economic reproduction and consumption remain sidelined. Analytical devices such as the urban ‘footprint' and sustainability indicators and toolkits have communicated a range of issues to a wide audience in line with the Local Agenda 21 emphasis on changing individual lifestyle practices - they oversimplify complex social, economic and political urban issues. The scale of poverty, social and environmental degradation in mega-cities is unsustainable. Forty per cent of the world's urban population is predicted to be slum dwellers by 2030 (UNDP 2009, p.30, Davis 2006). City e conomic expansion, for which global service connectivity is essential, could help to avert this but what would be the wider environmental outcomes of such development?
This depends on how city development is managed as a process (see for example Humphreys and Blowers 2009). Agglomeration has substantial environmental as well economic advantages over more thinly spread urban development patterns. Satellite images indicate that the present world urban space (including urban green space) covers just 2.8 per cent of the earth's land area which means that the whole world urban population would fit on less than half of Australia (UNFPA 2007, p.45). As already discussed, global connectivity stimulates innovation and investment in cities which can result in improved technologies to support efficient resource use, such as water and energy and communications systems such as public transportation and ICT. It is not building design and construction in high density new development which is the principal challenge in places where finance capital flows strongly through globalizing cities but institutional arrangements governing regulation and financing (especially for retrofit in mature cities). Thus although the ecological modernization thesis, discussed in the Blowers and Pain 1999 paper, has been a product of neo-liberal strategy, the capacity for globalizing cities to innovate and create less environmentally compromising robust development strategies is now substantial.
An even greater challenge is the problem of lower density development which now characterizes developing as well developed world regions. Suburbanization, urban sprawl and peri-urbanization are differently constituted functionally, economically and socially, however they share a common problem of a lack of adequate spatial governance arrangements. Even mature polycentric urban regions with a dispersed pattern of ‘deconcentrated concentration', regarded as a sustainable urban form in European policy since 1999, have been shown to compromise agglomeration economies and generate intense cross-cutting movement which cannot be supported effectively by public transport (Kloosterman and Musterd 2001, Hall and Pain 2006). These new city spaces (variously referred to as mega-regions, global- and mega-city regions, see Chapter X of this Reader) comprise conflictual territorial, political relations and are effectively ungoverned (McGee and Robinson 1995, Lang and Dhavale 2005, Laquian 2005, Hall and Pain 2006, Regional Planning Association 2006).
In writing ‘The Unsustainable City?' Blowers and Pain were at pains to reflect the complex interrelations of cities that are structuring contemporary sustainability tensions. This complexity has increased as a result of the intensification of service network connectivity. The uneven world geography of development that the authors noted in 1999 is beginning to be countered to an extent in the case of China's economic ‘liberalization', but this Chinese city strategy is embedded in an ideological framework of strong state intervention and investment. The authors' questioning of the long-term sustainability of a neo-liberal strategy for cities remains open. Knowledge-intensive economic activity seems good news for cities because it promotes creative global intercity flows of knowledge, cultural diversity and finance that can feed a more sustainable development process. As Harvey has claimed, “Cities that cannot accommodate diversity, to migratory movements, to new lifestyles and to political, religious, and value heterogeneity, will die either through ossification and stagnation or because they will fall apart in violent conflict.” (1996, pp. 437-438).
Dense cities are centres of education, cultural, social, health and work opportunities, they can also constitute a more environmentally sustainable development form than dispersed settlements. They can encapsulate what Soja has termed “generative” and “innovative”, “synekistic agglomeration” - a “behavioural and transactional as well as political and economic concept” similar to Jacobs' “spark of economic life” (2000, pp.13-14). However, as Manuel Castells has cautioned (1998), these urban assets are unequally shared even within the richest of the world's cities, and city - non-city relations are now polarizing (see for example Humphreys 2006, Neuwirth 2005), leading to ongoing rural-urban economic migrations. What seems clear however is that nuanced governance approaches can facilitate “a progressive transformation of economy and society” (Wheeler and Beatley 2004, p.56) by ‘opening up' to globalization. The politics of governance remains as important as it was in 1999 in shaping the strategies of large cities which can lead to a more, or less, sustainable development process.
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Note: This Research Bulletin has been published in B. Derudder, M. Hoyler, P.J. Taylor and F. Witlox (eds) (2012) International Handbook of Globalization and World Cities Cheltenham, UK, Northampton, MA, USA: Edward Elgar, pp. 318-327.