SOCIETIES CONSUMING NATURE: A PANEL STUDY OF THE ECOLOGICAL FOOTPRINTS OF NATIONS, 1960-2003* Andrew K. Jorgenson Department of Sociology and Anthropology North Carolina State University Brett Clark Department of Sociology and Anthropology North Carolina State University Running Head: Consuming Nature: A Panel Study Word Count: 15,896 (including endnotes and references) Working Draft * Direct all correspondence to Andrew K. Jorgenson, Department of Sociology and Anthropology, North Carolina State University, Campus Box 8107, Raleigh, NC 276958107; Phone: (919) 515-9023; FAX: (919) 515-2610; email: akjorgen@sa.ncsu.edu. SOCIETIES CONSUMING NATURE: A PANEL STUDY OF THE ECOLOGICAL FOOTPRINTS OF NATIONS, 1960-2003 ABSTRACT The human dimensions of global environmental change are among the most pressing issues facing the world today. While increasing attention is paid to such issues, most sociological research on society / nature relationships is narrowly framed, limited in temporal and unitary scope, and lacking methodological rigor. To help resolve these shortcomings, the authors conduct fixed effects and random effects panel regression analyses of the per capita ecological footprints of 69 nations from 1960 to 2003 to evaluate multiple theoretical traditions within environmental sociology and other related orientations. Findings indicate that the consumption-based environmental impacts of human activities are tied to economic development, urban population, militarization, and the structure of international trade. Ecological conditions in the context of climate and biogeography also prove to partially condition the environmental harms of nations. Ultimately, this research suggests that political-economic factors, ecological milieu, and structural associations between nations all influence society / nature relationships. Considering the globally unsustainable levels of resource consumption and concomitant increases in pollution for a growing number of nations throughout the world, the authors contend that comparative investigations on such topics should be more central to the discipline. 1 CONSUMING NATURE: ENVIRONMENTAL SOCIOLOGY AND A PANEL STUDY OF THE ECOLOGICAL FOOTPRINTS OF NATIONS, 1960-2003 INTRODUCTION There is scientific consensus that humans fundamentally alter the global environment and that the scale of recent environmental transformations is unprecedented. In the last fifty years, two-thirds of the world’s ecosystems have been overexploited and / or polluted (Millennium Ecosystem Assessment 2005). Human activities are the primary forces responsible for the observed warming of the earth’s atmosphere and the associated ecological consequences of climate change (Intergovernmental Panel on Climate Change 2007). Furthermore, no area of the world’s ocean is unaffected by human influence, undermining the services and biodiversity of its ecosystems (Halpern et al. 2008). Although physical and natural scientists underscore that human impacts on the natural world are escalating and radically changing natural processes and cycles (Vitousek et al. 1997), a deeper understanding of the anthropogenic drivers of environmental change and the social influences on ecological crisis and sustainability is still needed. Additionally, the dynamic interaction between nature and society raises pressing concerns regarding our conception of ecological relationships. Environmental sociology places society, in all of its grandeur, within the bounds of natural influences (e.g., Buttel 1987, 2000; Catton and Dunlap 1978; Dunlap and Catton 1979; Foster 1999; Goldman and Schurman 2000; York, Rosa, and Dietz 2003). The environment is a social issue, and the environment’s role in shaping—both in terms of constraining and facilitating societies—is recognized. At the same time, attention is 2 paid to how societies transform the biophysical world—whether it is through the organization of the economic system, demographic trends, political mobilization, or other structural factors (e.g., Bunker 1984; Downey 2006; Ehrhardt-Martinez 1998; Jorgenson 2006b; Redclift and Sage 1998; Roberts and Parks 2007; Schofer and Hironaka 2005). Thus, environmental sociology attempts to address the economic, political, and social dimensions of our ecological relationships. It investigates environmental issues at both micro and macro levels, from individual consumer behaviors to the international movement of toxics, from specific forms of environmental degradation to the health risks associated with exposure to dangerous chemicals. Like other areas of the discipline, environmental sociology has undergone numerous reconfigurations, as various theoretical traditions continue to grapple with ecological concerns and the relationship between society and nature. Different orientations privilege certain factors and structural relationships—such as economic growth, technological development, position in the global economy, degree of modernization, or population dynamics—over others, in part due to the questions being asked, the state of the field, and the limitations of data. Here we undertake cross-national analyses that engage many of the most prominent theoretical traditions within environmental sociology (treadmill of production, metabolic rift, world-systems, and ecological modernization) that focus on the environmental consequences of development, affluence, and the structure of the world economy, as well as more recently emerging theoretical perspectives (treadmill of destruction, domestic economy structure, ecologically unequal exchange, urban political-economy, and structural human ecology) that address other sorts of human / environment relationships. We assess a broad range 3 of theoretically derived variables in regard to their consumption-based environmental impacts, measured as the per capita ecological footprints of nations. While our analyses draw upon previous macrosociological research on the environment, it makes significant advances employing panel data to better conceptualize historical patterns and relationships; considering and synthesizing a broader range of theoretical traditions; and giving serious attention to how both social and ecological conditions influence each other and to how they play out over time in comparative perspective. As a result, we are able to assess the explanatory power of different sociological theories and to identify significant and persistent factors that condition and influence the varying consumptionbased environmental burdens of nations. We begin with discussions about the most prominent environmental sociology theories and other relevant perspectives, and explicate particular relationships that we investigate in the ensuing panel analyses. Next, we describe the substantive characteristics of the ecological footprint while also highlighting its utility and importance as an empirical measure. In this discussion we also examine the crossnational temporal patterns of per capita footprints relative to globally sustainable levels of resource use. We then describe the employed panel regression methods, variable definitions and data sources, and countries included in the tested models. Next, we present and discuss the findings for the panel analyses, which identify the variables and theoretical positions that help illuminate the relationships and conditions that are most influential in shaping the consumption-based environmental impacts of nations. We conclude by highlighting the key findings of the study and we discuss their theoretical significance. 4 SOCIOLOGICAL APPROACHES TO SOCIETY / NATURE RELATIONSHIPS A variety of theoretical perspectives have developed—sometimes as an outgrowth of classical social theory—within environmental sociology and other related areas of inquiry. The perspectives of interest in this study are ecological modernization (e.g., Mol 1995), the treadmill of production (Schnaiberg 1980; Schnaiberg and Gould 1994), the metabolic rift (Clark and York 2005; Foster 1999; Burkett 1999), world-systems and the environment (e.g., Chase-Dunn 1998; Jorgenson and Kick 2006; Roberts and Grimes 2002), treadmill of destruction (Hooks and Smith 2004), and ecologically unequal exchange (e.g., Bunker 1984; Jorgenson 2006a; Rice 2007a). We also consider different theoretical orientations concerning the environmental impacts of the structure of domestic economies (e.g., OECD 1998) as well as urban conditions (e.g., Dickens 2002; Molotch 1976) and structural human ecology (e.g., Dietz, Rosa, and York 2007). These various approaches are not necessarily exclusive, given that at times arguments compliment each other and researchers have contributed to more than one tradition. We argue that most environmental concerns and questions suggest the need for synthesis between specific theoretical orientations. Nevertheless, brief synopses of these positions will illuminate how they conceptualize human / environment relationships in the modern world. Through engaging these theories, we aim to identify the dominant structural conditions and relationships that are proposed to impact the environment, which we assess in subsequent panel analyses. We begin with discussions of the perspectives that address the environmental consequences of economic development and related conditions, followed by summaries of the other orientations and their arguments of most relevance for the current study. 5 Economy and Environment: Multiple Perspectives Ecological Modernization and the Environmental Kuznets Curve One of the dominant theoretical orientations within contemporary environmental sociology is ecological modernization (Mol 1995). This theory asserts that the ongoing development of the market, technology, and industrialism will lead society away from actions that cause environmental degradation and to a more sustainable interaction between humans and the environment. It is argued that the power of the market can bring about ecological reform. Ecological modernization theory builds upon a branch of environmental economics that recognizes that economic growth has generated environmental harms, but argues that further economic development can correct these problems (Grossman and Krueger 1995). 1 The environment is seen as a luxury good, subject to public demand through the workings of an advanced market. In other words, during the early stages of economic development, environmental impacts escalate, but as the affluence within these societies rises, the value the public places on the environment—including wilderness, clean air, and clean water—will increase. The public desire for environmental quality— in large part expressed as consumer demand for “green” products and services—will, economists expect, place pressure on the government and businesses to invest in “ecofriendly” technologies and commodities. It is argued that if the market is allowed to operate without dramatic interference, continuing economic development will lead to a leveling and eventual decline in the environmental impacts of societies. The proposed trend, known as the environmental Kuznets curve, is depicted as an inverted U-shaped 6 distribution representing the relationship between environmental impacts and economic development. Ecological modernization continues along these lines, insisting that the only “possible way out of the ecological crisis is by going further into the process of modernization” (Mol 1995:42). The forces of modernization that are believed to lead human society from its past of environmental degradation and exploitation to environmental sustainability are the institutions of modernity, including the market, industrialism, and technology (Mol 1995, 1996, 2001, 2002; Mol and Sonnenfeld 2000; Spaargaren 2000; Spaargaren and Mol 1992). Ecological modernization theorists assert that environmental degradation is not an inherent characteristic of economic development. They contend that the forces of modernization, such as technological advances, will lead to the dematerialization of society and the decoupling of the economy from energy and material consumption, allowing human society to transcend environmental problems (Mol 1995, 1997; Leadbeater 2000). Ecological modernization theorists argue that the advance of modernization will lead to the emergence of an “ecological rationality,” where environmental concerns are incorporated into social decision-making, and ecological costs and benefits are weighed along with economic considerations (Mol 2001). This will lead to a shift away from the pure economic rationality that prevailed in earlier stages of modernization. What they are proposing is an ecological-economic rationality that explicitly recognizes the inputs of the environment into the economy. This green rationality will provide the knowledge of how to properly extend economic valuation to the environment and any natural services that it produces—with the help of environmental regulation. Additionally, new 7 technologies and further research innovations will develop to resolve environmental problems and to enhance the environmental sustainability of society, without significant restructuring of the market (Hajer 1996). In summary, the ecological modernization of society will lead to the “ecologization of economy” and the “economization of ecology” (Mol 2000:15). The former refers to organizational changes in both the production and consumption processes of society, making them account for prevailing environmental interests. The latter entails the extension of economic valuation to the environment and any natural services that it produces. In the analyses below, we consider the premises of ecological modernization, which asserts that ecological rationality has significantly influenced economic development and concomitant environmental conditions. More specifically, we investigate ecological modernization’s assertion that higher levels of economic development lead to declines in the consumption-based environmental impacts of nations. We also use appropriate measures to look for the presence of an environmental Kuznets curve. Treadmill of Production Theory The treadmill of production theory runs counter to ecological modernization theory. Proponents of this position argue that environmental degradation stems from the incessant expansion of production to maintain profits, and that environmental sustainability cannot be obtained within a capitalist society (Schnaiberg 1980; Schnaiberg and Gould 1994). Technological development leads to the expansion of production, so the total amount of energy and materials used typically increases. Producers attempt to 8 externalize environmental costs to increase their profits. Economic growth, premised on accumulation, is thus likely to increase environmental degradation. Schnaiberg posits that any society driven by endless economic expansion is mired in a conflict with nature, given the increasing scale of human demands upon the finite world. Such a society is running endlessly, faster and faster, expending energy and resources at an accelerating pace. The treadmill on which society is caught operates in a particular, historical way. “The basic social force driving the treadmill is the inherent nature of competition and concentration of capital” (Schnaiberg 1980:230). An increase in monetary resources allows for monopoly capital to invest in new technologies, which necessitates the incorporation of more energy to operate industry. The new technologies advance the displacement of labor, which helps reduce labor costs and allows for an expansion in the productive capacity of capital. The relentless commitment to economic growth, despite the various social and ecological costs, is dictated by the pursuit of profit. Producers try to enlarge the operations of production continuously. With the support of government, industrial production is allowed to expand, increasing the demands placed on nature and creating ever-greater amounts of waste (Schnaiberg 1980; Schnaiberg and Gould 1994; Schnaiberg, Pellow, and Weinberg 2002). Producers will not freely internalize the environmental costs of production, because it would reduce their profits. The economic power of producers influences politics and prevents major reforms that would threaten their authority. The state helps support the expansion of capital by expanding consumer credit, which keeps pace with increases in production (Weinberg, Pellow, and Schnaiberg 2000:34). 9 Gould, Pellow, and Schnaiberg (2004:297) explain that the treadmill of production theory is “primarily an economic change theory, but one that has direct implications for natural resource extraction as well as for the opportunity structure for workers.” While workers are displaced, they note, by the incorporation of new machines and technologies in production, social progress is associated with ongoing growth. So the public, in general, continues to support the expansion of the economy, as it continues to invest in its productive capacity. At the same time, the degradation of life and nature continues to worsen. “The ‘treadmill’ component recognizes that the nature of capital investment leads to higher and higher levels of demand for natural resources…. For ecosystems, each level of resource extraction becomes commodified into new profits and new investments, which leads to still more rapid increases in demand for ecosystem elements” (Gould, Pellow, and Schnaiberg 2004:297). Nature is used to fuel industry and to produce commodities for the market, and the production process generates an increasing volume of wastes that are released into the natural world. Treadmill of production theorists hope that the dislocations and continuous degradation of the world will culminate in a public interest for education regarding alternatives to the treadmill society, otherwise, it will be impossible to slow or reverse its path of environmental deterioration (Schnaiberg 1980:250; Obach 2004). The treadmill of production theory provides a model of the productive operations of society as they exist in relation to a finite world. The withdrawals and additions to nature, in the form of raw materials and pollution, are “biophysical variables” that can be measured in relation to economic growth. Such analyses highlight the “enduring conflict” between society and the environment (Schnaiberg and Gould 1994). The 10 treadmill of production perspective illuminates issues of the scale and intensity of production as well as economic growth and exploitation of natural resources. The implication of this model is that there is an increase in environmental problems as society moves along on the treadmill. More generally, treadmill of production theory would propose that economic development will lead to higher consumption-based environmental demands. The Metabolic Rift The metabolic rift perspective combines Marx’s critique of political-economy and metabolic analysis, in order to conceptualize the interpenetration of nature and society and to understand the “complex, dynamic interchange between human beings and nature,” which involves “material exchanges” and “regulatory action” (Foster 1999:381). In contrast to other environmental sociology perspectives, metabolic research incorporates an analysis of natural cycles and systems, attempting to address both quantitative and qualitative dimensions of socio-ecological relationships. It recognizes that ecosystems embody specific regulatory processes that involve complex relationships of interchange that aid in their regeneration and continuance. The labor process constitutes a metabolic relation of exchange between humans and nature that is situated and organized by the larger economic system. It notes that capitalism is predicated on the ceaseless accumulation of capital, which produces a specific social metabolic order. The social metabolism of capitalism is increasingly separated from natural metabolism, producing metabolic rifts (ruptures) in natural cycles and processes. As a result, this leads to a violation of the nature-imposed regulative laws of social production that maintain the conditions of nature, leading to further ecological degradation. 11 Marx’s metabolic analysis, as explicated by Foster (1999, 2000), provides an examination of capitalism as a metabolic order. Metabolic analysis in this context emerged out of his studies of agriculture and the depletion of soil, where Marx noted that the soil required specific nutrients—nitrogen, phosphorus, and potassium—to maintain its ability to produce crops, because as crops grew they took up these nutrients. In earlier societies, the produce of nature was recycled back to the land as fertilizer after it was consumed. But “capitalist production collects the population together [due to the enclosure movement and the concentration of land] in great centres, and causes the urban population to achieve an ever-growing preponderance” (Marx 1976:637). This created a division between town and country. Food and fiber were shipped from the countryside to distant markets. In this, the nutrients of the soil were transferred from the country to the city where they accumulated as waste and increased pollution, rather than being returned to the soil. This type of production “disturbs the metabolic interaction between man and the earth, i.e. it prevents the return to the soil of its constituent elements consumed by man in the form of food and clothing; hence it hinders the operation of the eternal natural condition for the lasting fertility of the soil” (Marx 1976:637). As a consequence, a rupture is created in the nutrient cycle. Influenced by an economic system premised on the accumulation of capital, intensive agricultural practices were implemented to increase the yield of food and fiber for markets in cities. The transfer of nutrients was tied to the accumulation process and increasingly took place at the national and international level. Nutrients turned to waste in the cities and were not recycled back to the land. As a result, the riches of the soil 12 were squandered and the soil was continually depleted of its necessary nutrients (Foster 1999). 2 While Marx specifically examined the soil crisis in the 1800s, his metabolic analysis has been employed by sociologists to study contemporary environmental problems such as global climate change (Clark and York 2005), the oceanic crisis and the collapse of global fisheries (Clausen and Clark 2005), and persistent agricultural problems (Mancus 2007). Metabolic rift analysis illuminates social-natural dislocations associated with economic growth. The town and country division—whether within a nation or internationally—removes organic matter from its particular ecosystem and concentrates it in urban settings, both undermining and overwhelming ecosystems. Metabolic rift analysis suggests that economic growth—predicated on the accumulation of capital—leads to environmental degradation through the separation of social and natural systems. It indicates that ecological degradation takes place in multiple ways: 1) an economic system predicated on constant growth undermines natural cycles and processes; and 2) the rupture of natural systems leads to the accumulation of waste and the production of pollution. In the following analyses, we examine several of these relationships, in regard to changes in rural / urban populations, economic growth, and the structure of international trade. World-Systems: The Division of Nations and Nature Society / nature relationships have become quite prevalent in world-systems analyses in recent decades (e.g., Goldfrank, Goodman, and Szasz 1999; Hornborg, McNeill, and Martinez-Alier 2007; Jorgenson and Kick 2006; Moore 2003; Roberts and Grimes 2002). Wallerstein (1974) and many others (e.g., Chase-Dunn 1998; Chase-Dunn 13 and Grimes 1995) argue that all nations are structurally interconnected and form a single world-system (see also Mahutga 2006; Smith and White 1992; Snyder and Kick 1979). With the emergence of capitalism in the long sixteenth century, pre-capitalist modes of production were eliminated as the new economic system expanded around the globe. Capitalism, as the dominant mode of production, consists of an integrated social system composed of interacting subsystems held together through conflicting forces and longterm historical processes. This arrangement, with divisions between the core, semiperiphery, and periphery, facilitates the unequal accumulation of capital between spheres within the global economy. The constant drive for accumulation, the concentration of military strength in the hands of the dominant capitalist nations, and the division of the world into an economic-political hierarchy helps maintain the stratified world-system (Kentor 2000). Accompanying the division of the world is a division of nature, as the structure of the world-system facilitates the transfer of raw materials—such as timber, fiber, minerals, and oil—from the periphery and semi-periphery to the core (e.g., Bunker 1984; Moore 2000). In a related vein, Frey (1994, 1995) demonstrates how core nations transfer hazardous materials to countries in the periphery, and McKinney, Fulkerson, and Kick (2008) illustrate how world-systemic processes contribute to increases in threatened bird species, particularly in non-core regions. Other comparative research indicates that the scale and intensity of greenhouse gas emissions and other air pollutants are strongly tied to the structure of the core / periphery hierarchy (e.g., Jorgenson 2006a; Roberts, Grimes, Manale 2006; York and Rosa 2006). Of more relevance for the current study, recent analysts posit that a resource consumption / environmental degradation “paradox” exists 14 where core nations consume the highest amounts of natural resources compared to noncore nations, yet they tend to have the relatively lowest levels of particular forms of environmental degradation within their borders (e.g., deforestation). It is argued that these inverse relationships are largely structured and maintained by the stratified interstate system (e.g., Jorgenson 2003, 2005; Jorgenson and Burns 2007). The worldsystems perspective, which complements treadmill of production theory, the metabolic rift approach, and ecologically unequal exchange theory (discussed below), helps capture the global movement of capital, raw materials, and waste. More specifically, this perspective would propose that more affluent and powerful nations exhibit higher consumption-based environmental demands. Urban Political-Economy and the Environment Urban sociology has long been concerned with environmental issues. In fact, urban environmental justice studies began with Frederick Engels’s seminal work The Condition of the Working Class in England in 1844. Here Engels (1892) examined the environmental conditions in the manufacturing establishments and slums of the factory towns of England. The depopulation of the countryside and the expanding industrial operations were drawing people to the cities. Engels studied the transformations of the urban landscape, highlighting widespread pollution, laying the grounds for the development of social epidemiology, and revealing the gross economic inequalities. Workers were often forced to reside within polluted urban landscapes where the natural conditions and their health were deteriorating (Cronon 1991; Davis 2002; Engels 1892). Ongoing work that focuses on urban political-economy and ecology addresses issues related to cities as centers of growth (population, economic, sprawl) with 15 structured environments that generate ecological contradictions (Bookchin 1974; Davis 2002; Dickens 2002; Downey 2005; Molotch 1976; Mumford 1970). Molotch (1976:318) argues that cities are growth machines, generally captured by interests focused on expanding profit, which “almost always brings with it the obvious problems of increased air and water pollution, traffic congestion, and overtaxing of natural amenities. This dysfunction becomes increasingly important and visible as increased consumer income fulfills people’s other needs and as the natural cleansing capacities of the environment are progressively overcome with deleterious material.” The great concentrations of population within mega-cities pose severe ecological concerns, as nature is increasingly urbanized with sprawling cities that consume vast amounts of water, raw materials, and energy that is appropriated from already stressed environments in distant places (Dickens 2002; Gonzalez 2005, 2006). Gonzalez (2005) demonstrates that urban zones are centers of mass consumption, whether it is services or commodities. Land developers promote urban sprawl, and highway systems impose transportation infrastructures that require the use of high quantities of resources in the daily operation of business and people’s lives. One end result of this type of built environment is the burning of fossil fuels, which contributes to global warming and climate change. Consistent with the arguments of these urban political-economy perspectives as well as prior cross-national investigations (Ehrhardt-Martinez 1998; Jorgenson 2003; York et al. 2003), we consider it crucial to consider the environmental impacts of urban populations, net of the effects of other factors. 16 The Military, Treadmill of Destruction Theory, and the Environment Recent sociological investigations address how different aspects of the military influence levels of domestic income inequality (Kick, Davis, and Kentor 2006), economic development (Levy 1998), and other social outcomes (Jenkins and Scanlan 2001; Kick et al. 1998). However, with few exceptions (e.g., Jorgenson 2005; Hooks and Smith 2004, 2005; York forthcoming), theorization and research on the environmental impacts of militarism are non-existent in sociology. The effects of warfare on the environment reveal how important it is to consider the potential environmental harms of military institutions and behaviors (e.g., Davis 2002; Grimes 1999; Lanier-Graham 1993; Thomas 1995), but as York (forthcoming) suggests, they do not represent the full extent of the environmental impacts of the military. Even when armed conflicts are not taking place, military institutions and their activities are likely to consume vast amounts of nonrenewable energy and other resources for research and development, maintenance, and operation of their overall infrastructure and hardware (e.g., Dycus 1996; Sidel and Shahi 1997). At the same time, they generate large amounts of toxic substances and waste (LaDuke 1999; Shulman 1992; Ward 1999). Furthermore, according to the United Nations’ Center for Disarmament (1982), the amount of land used by armed forces for bases and other forms of installations as well as for training exercises has risen steadily over the last century. A network of military bases encompasses the globe, requiring a vast amount of resources to staff, operate, and transport equipment and personnel between destinations. Military-oriented resource use also includes the strategic stockpiling of fuels and other materials, and consumption is further increased through the material requirements of industries that produce marginal 17 equipment for the armed forces and its support economy. Production of these forms of marginal equipment and stockpiling of fuels helps to expand and maintain the overall military infrastructure. The populations of armed forces also consume vast amounts of food, and use large quantities of various organic as well as synthetic materials for uniforms and more specialized forms of clothing (Jorgenson 2005). Besides consuming resources, peacetime activities of the military are known to generate different forms of waste. For example, the armed forces consume large amounts of fossil fuels, which directly contribute to anthropogenic carbon dioxide emissions and the emission of other greenhouse gases known to impact global warming and climate change (Roberts et al. 2006). Renner (1991) estimates that petroleum products for land vehicles, aircrafts, sea vessels, and other forms of machinery account for approximately 75 percent of all energy use by the armed forces worldwide, and some analysts posit that the Pentagon is the largest consumer of nonrenewable energy resources, particularly fossil fuels, in the United States and quite possibly the entire world (Hynes 1999; Santana 2002). The vast network of military bases around the globe only increases the consumption of fossil fuels, and superior combat performance of equipment is likely of greater priority than energy efficiency for military institutions. What is more, the production, testing, maintenance, and disposal of conventional, biological, chemical, and nuclear arms generate toxic and radioactive substances that are known to contaminate air, water, and soil (Davis 2002; LaDuke 1999; Renner 1991; Shulman 1992). Recently, Hooks and Smith (2004, 2005) formulated a theoretical orientation for assessing the potential environmental impacts of militaries. 3 They characterize the expansionary dynamics and profound environmental impacts associated with militarism 18 as the “treadmill of destruction.” Drawing partly from long-standing perspectives in political sociology (e.g., Mann 1988; Tilly 1990), Hooks and Smith (2005) argue that primarily for geopolitical reasons, states—not classes or firms—declare and wage wars. While military institutions and activities are indeed connected to economic interests and the treadmill of production (Kalecki 1972; Schnaiberg 1980), they are also somewhat independent of them. However, like the treadmill of production, the fundamental logic of the treadmill of destruction undermines environmental protection concerns. The latter is clearly articulated by a U.S. military base commander during a community hearing in Virginia (Renner 1991:152): “We are in the business of protecting the nation, not the environment.” Geopolitical competition often drives arms races as well as concomitant technological advances and infrastructural development. However, military development under these conditions does not necessarily involve increases in armed forces’ personnel (Hooks and Smith 2005). Especially for developed nations, the environmentally damaging capabilities of militarism are often partly a function of technological developments with weaponry and other machinery that require less soldiers for their possible use. While the scale of their material infrastructure may increase, become more spatially dispersed, or at least remain relatively constant, the overall social space (i.e., population) occupied by more technologically advanced militaries often shrinks (e.g., Kick et al. 2006). In a similar vein, political-economic sociologists have emphasized that nations with relatively larger and more technologically advanced militaries utilize their global military reach to gain disproportionate access to natural resources (Chase-Dunn 1998; Kentor 2000; Magdoff 1969, 1978; Podobnik 2006). While prior cross-national 19 research investigates the environmental impacts of either military personnel size (York forthcoming) or military expenditures (Jorgenson 2005), we consider it crucial to assess the consumption-based environmental impacts of both. Domestic Economy Structure Neoclassical economic perspectives suggest that the structure of domestic economies is likely to influence their consumption-based environmental demand (e.g., OECD 1998). A common assertion derived from this general framework is that a relative shift towards a more service-based economy offers a potential solution to reducing the scale and intensity of the environmental impacts of nation-states (Leadbeater 2000). Following this line of reasoning, one could posit that countries with more service-based economies will have lower consumption- and production-based environmental impacts. Moreover, countries with a larger manufacturing base will likely consume greater amounts of resources and emit higher levels of waste, such as greenhouse gas emissions, ground-level air pollutants, and industrial water pollutants. In contrast to neoclassical arguments, critical political-economic perspectives, such as world-systems and structural globalization approaches to the environment (e.g., Jorgenson and Kick 2006; Roberts and Grimes 2002), posit that many serviced-based economies are nested in more affluent societies, and more affluent societies utilize their relative positions of international power and influence to gain greater access to and ultimately consume vast amounts of resources—while social and environmental costs are imposed on other societies and nature. Moreover, often the most efficient nations are, in fact, the biggest consumers of natural resources, and economic growth and expansion typically outstrip gains made in efficiency (Foster 2002; Jorgenson 2008; York and Rosa 20 2003; York et al. 2003). These approaches further suggest that the perceived or real environmental benefits of having a more service-based economy might be outstripped by the overall environmental harms associated with economic development or affluence, since in the contemporary world economy the latter often go hand-in-hand with higher levels of service-sector activities (Jorgenson and Burns 2007; York 2006). For example, the most powerful global cities are located in more-developed countries (Alderson and Beckfield 2004). These cities, often considered as “command points” 4 and financial centers for global production systems, house the most lucrative “producer services” 5 that cater to transnational firms headquartered in global cities (Sassen 2001), many of which organize and largely control global economic activities. To the extent that countries turn to manufacturing, critical political-economic perspectives generally agree with the neoclassical economic assertion that economies with a greater intensity of secondarysector activities will likely consume greater amounts of resources and emit higher levels of waste (e.g., Jorgenson 2007; York and Rosa 2006). Thus it is important to consider the environmental impacts of the extent to which nations’ economies are manufacturingbased and service-based. Ecologically Unequal Exchange Environmental sociology has experienced a recent surge in theorization and research concerning how the structure of international trade contributes to ecological and environmental outcomes (e.g., Hornborg et al. 2007; Jorgenson and Kick 2006). Considering the recent upswings in structural economic globalization (e.g., Chase-Dunn, Kuwano, and Brewer 2000), the growing attention paid to the environmental impacts of trade is perhaps not too surprising. One of the primary perspectives in this emergent area 21 of literature is the theory of ecologically unequal exchange, which has much of its roots in the classical unequal exchange and trade dependence traditions in political-economic sociology (e.g., Amin 1974; Emmanuelle 1972; Frank 1967; Galtung 1971) as well as Stephen Bunker’s (1984) seminal work on natural resource extraction and underdevelopment in the Amazon. Bunker forcefully argued that macrosociology had failed to address how and the extent to which the extraction and export of natural resources from less-developed, peripheral countries (1) involve a vertical flow of value embodied in energy and matter to more-developed countries, and (2) could greatly influence the environmental and structural contexts in which subsequent development efforts unfold (Bunker 1984; see also Bunker and Ciccantell 2005; Hornborg 1998, 2001, 2006; Moore 2003; Rice 2007a). Drawing from these complementary perspectives, the contemporary theory of ecologically unequal exchange asserts that through the “vertical flow of exports” from less-developed countries, more-developed countries partially externalize their consumption-based environmental costs to less-developed countries, which in turn increase forms of environmental degradation in the latter while suppressing levels of resource consumption within their borders, often well below globally sustainable thresholds (e.g., Jorgenson 2006b; Rice 2007b; Roberts and Parks 2007; Srinivasan et al. 2007). Similarly, a global metabolic rift perspective suggests relationships of ecologically unequal exchange, given the organization of the global economy and the ruptures in global ecosystems (Clark and York 2005). In general, the populations of more-developed countries are positioned advantageously in the contemporary world economy, and thus more likely to secure and maintain favorable terms of trade allowing 22 for greater access to the natural resources and sink capacity of bioproductive areas within less-developed countries. This greater access facilitates the externalization of environmental costs of resource extraction and consumption to less-developed countries. Furthermore, these structural processes help create conditions where more-developed countries are able to over-utilize global “environmental space” (as well as the global commons, such as the atmosphere and oceans), which encompasses the stocks of natural resources and waste assimilation properties of ecological systems supporting human social organization (Rice 2007a). 6 The misappropriation of environmental space suppresses resource consumption opportunities for many less-developed countries, which also impacts the health and well-being of their domestic populations (Jorgenson forthcoming). To assess key aspects of the theory of ecologically unequal exchange, in the subsequent panel analyses we employ a weighted measure that quantifies the relative extent to which the exports of a given country are sent to more-developed countries. We also use a theoretically relevant interaction variable to compare the effects of ecologically unequal exchange for less-developed countries and developed countries. Structural Human Ecology Human ecologists argue that while the capacity of social institutions, technology, and culture, separate humans from other species, this unique capacity is to some extent bounded by the limits imposed by ecological conditions (York et al. 2003:283; see also Dunlap and Catton 1979; Freese 1997a, 1997b). However, sociological research focusing on the environmental impacts of political-economic conditions and processes (e.g., Burns et al. 1994; Jorgenson et al. 2007; Schofer and Hironaka 2005; Rice 2007a; Shandra 2007) typically fails to consider the ecological context in which social factors drive 23 environmental outcomes (Catton 1980; Hawley 1950). More specifically, structural human ecologists argue that ecological factors, such as biogeography (e.g., arable land) and climate (e.g., latitude), play critical roles in influencing and conditioning how socialstructural factors affect the natural environment (e.g., Dietz and Rosa 1994; Dietz et al. 2007; Rudel 2005). Biogeography in this context deals with the extent to which resource density and availability influence resource demand and consumption levels. Regarding the second ecological factor (i.e., climate), conventional wisdom suggests that more resources are consumed to sustain societies in colder climates. Thus, one would assume that resource consumption increases the further a nation is from the equator (Diamond 1997; York and Rosa 2006). Considering the potential for invalid inferences, coupled with the robust findings concerning these sorts of ecological factors in comparative human ecological research (e.g., York et. al 2003), in the following analyses we include controls for both climate and biogeography. THE ECOLOGICAL FOOTPRINTS OF NATIONS The ecological footprint is perhaps the most comprehensive measure currently available for assessing global environmental sustainability issues. Thus, to evaluate the various theoretical perspectives discussed in preceding sections, we employ the per capita ecological footprint as the dependent variable in subsequent panel analyses. Conceptually, and as an empirical indicator, the ecological footprint was primarily developed by Mathis Wackernagel and William Rees (1996), and quantifies the amount of biologically productive land required to support the consumption of renewable natural resources and assimilation of carbon dioxide waste products of a given population. National footprints are measures of societal consumption-based demand upon domestic 24 as well as global natural resources, and they allow for comparisons of a nation’s environmental demand relative to available domestic and global “natural capital.” The latter refers to the stock of natural assets, such as water and forest resources, producing a flow of services and resources for human societies (Wackernagel et al. 1999). The recently updated national footprint estimates available from the Global Footprint Network (2006) measure the bio-productive area required to support consumption levels of a given population from cropland (food, animal feed, fibre, and oil); grassland and pasture (grazing of animals for meat, hides, wool, and milk); fishing grounds (fish and seafood); and forest (wood, wood fibre, pulp, and fuelwood). 7 They also include the area required to absorb the carbon dioxide released when fossil fuels are burned, and the amount of area required for built infrastructure (e.g., roads, buildings). Regarding the former, the carbon dioxide portion of the footprint deals explicitly with natural sequestration, which involves the biocapacity required to absorb and store the emissions not sequestered by humans, less the amount absorbed by the oceans. 8 A relatively new addition to the comprehensive footprint measure is the nuclear footprint subcomponent. Due to lack of conclusive and available data, the nuclear energy portion of the footprint is assumed to be and thus estimated as the same as the equivalent amount of electricity from fossil fuels. However, this subcomponent accounts for less than 4 percent of the total global footprint in the year 2000, and this percent is even lower for earlier years. The ecological footprint is measured and reported in global hectares, and is calculated by adding imports to, and subtracting exports from, domestic production. In mathematical terms, consumption = (production + imports) – exports. This balance is 25 calculated for more than 600 products, including both primary resources (e.g., raw timber, wheat, milk) and manufactured products that are derived from them (e.g., paper, plywood, cereal, cheese). Each product or category is screened for double counting to increase the consistency and robustness of the measures. To avoid exaggerations in measurement, secondary ecological functions that are accommodated on the same space as primary functions are not added to the footprints. The footprint calculations also use (1) equivalence factors to take into account differences in world average productivity among different land types (e.g., world average forest versus world average cropland), and (2) yield factors to take into account national differences in biological productivity (e.g., tons of wheat per U.S. or Sri Lankan hectare versus world average). The ecological footprint includes only those aspects of resource consumption and waste production for which the Earth has regenerative capacity and where data exist that allow this demand to be quantified in terms of bio-productive area (Wackernagel et al. 2002). Of particular relevance for the current study, the newly available time series footprint estimates are reported in constant 2003 global hectares, which allows for more valid temporal comparisons within and between countries. The per capita footprints of nations can be compared to the global biocapacity per capita, which is calculated by dividing all the biologically productive land and sea on earth by the total world population, which provides an estimate of the globally sustainable level of consumption. This indicator of sustainable consumption was also developed by Wackernagel et al. (2000) and is available from the Global Footprint Network. The series of boxplots in Figure 1 illustrate the relative distance between the per capita footprints and the global biocapacity per capita in five-year increments from 26 1960 to 2000 as well as the year 2003 for the countries included in the subsequent panel analyses. <Figure 1 about here> During the forty-three year period, the majority of nations represented in Figure 1 went from having globally sustainable levels of consumption-based environmental demand to unsustainable levels. Moreover, the cross-national distribution of consumption levels increased dramatically, with the majority of increases taking place upwardly and well above sustainable thresholds. Besides illustrating the changing relationships between the footprints of nations and corresponding points of global biocapacity, Figure 1 highlights the growing temporal and cross-national variation in the environmental impacts of human societies throughout the world. We now turn to the panel regression analyses, where we assess the extent to which the various sociological theories outlined above successfully help in explaining the differences in the per capita footprints of nations. THE ANALYSES The Dataset We analyze an unbalanced panel dataset consisting of data for 69 countries from 1960 to 2003. 9 With the exception of 2003, data are point estimates at five-year intervals (i.e., 1960, 1965, 1970, 1975, 1980, 1985, 1990, 1995, 2000). To maximize the use of available data, we allow sample sizes to vary among the tested models. For the tested models, overall sample sizes range from 236 observations to 543 observations, with mean observations per model ranging from 4.6 to 8.4 per country. Due to the relatively limited availability of data for the weighted export flows measures discussed below, the third and 27 final set of reported analyses are slightly reduced to the 1975-2000 period for 58 countries. The minimum number of observations per country in any reported model is 2, while the maximum number of observations per country in any model is 10. Appendix A lists all countries included in the study. Fixed Effects and Random Effects Models With the recent availability of panel data for the outcome investigated in the current analyses, we are able to employ estimation methods that deal with potential heterogeneity bias (Greene 2000; Wooldridge 2002). Heterogeneity bias in this context refers to the confounding effect of unmeasured time-invariant variables that are omitted from the regression models. Fixed effects (FE) and random effects (RE) models are two approaches designed to correct for the problem of heterogeneity bias, and these two methods have gained popularity in different areas of sociology (see Halaby 2004), including environmental macrosociology (e.g., Jorgenson 2007, 2008; Jorgenson, Dick, and Mahutga 2007; Jorgenson and Kuykendall forthcoming; York 2007, forthcoming). Both methods “simulate” unmeasured time-invariant factors as case-specific intercepts (e.g., Nielsen and Alderson 1995). 10 The FE model treats the case-specific intercepts as fixed effects to be estimated, equivalent to including dummy variables for N—1 cases. The RE model treats case-specific intercepts as a random component of the error term (Frees 2004; Hsiao 2003). For substantive and methodological reasons, in this study we use STATA (Version 9) software to estimate ordinary least squares (OLS) FE and generalized least squares (GLS) RE models with robust standard errors (Hamilton 2006). 11 28 FE models have the advantage of avoiding spurious relationships in panel data (e.g., Lee, Nielsen, and Alderson 2007), and they provide a stringent assessment of the relationships between independent and dependent variables, given that the associations between predictors and outcomes are estimated net of unmeasured between-case effects (e.g., Beckfield 2007). This modeling approach is quite robust against missing control variables, closely approximates experimental conditions, and allows for rigorous hypotheses testing (Hsiao 2003). However, FE models are inappropriate for perfectly or near-perfectly time-invariant variables, including ecological factors of direct interest for the current study. While the case-specific intercepts might control for such factors, we are unable to assess and compare their actual impacts relative to other predictors. Also, when one or more independent variables have relatively low (or no) variation across time for a noteworthy proportion of cases, FE models can suffer from extreme multicollinearity since variables under these conditions will be highly collinear with the case-specific fixed effects (Wooldridge 2002). The type of interaction used in the subsequent analyses to assess the possible impacts of ecologically unequal exchange for less-developed countries relative to developed countries do indeed involve no temporal variation for a negligible proportion of cases. Thus, we estimate GLS RE models for the analyses that include such interactions as well as time-invariant ecological factors. For the analyses that exclude the latter two types of predictors, results of Hausman test statistics (all statistically significant) indicate that FE models are more appropriate than RE models. Moreover, all FE and RE models include unreported period-specific intercepts (i.e., period effects), 29 which controls for the potential unobserved heterogeneity that is cross-sectionally invariant within years (e.g., Alderson and Nielsen 2002). Dependent Variable The dependent variable for the analyses is the updated estimates for the per capita ecological footprint, which we obtained directly from the Global Footprint Network. 12 These data are logged (ln) to minimize skewness. For a more detailed description (than the above discussion) of the calculations used for the updated estimates, see the 2006 Living Planet Report. Independent Variables We describe the independent variables in the order they are introduced in the analyses. The first eight predictors that we discuss are included in the reported FE models. Consistent with prior cross-national research, we include gross domestic product per capita (GDP per capita) as a measure of a nation’s level of economic development and affluence. These data, which are logged (ln) to correct for excessive skewness, are measured in 2000 constant U.S. dollars and obtained from the World Bank (2007). All other variables in the study that are logged (ln) are done so for analogous reasons. Arable land per capita (ln) measures in hectares the amount of arable land per person in a given country. To calculate this variable, we obtained estimates of total arable land in hectares from the World Resources Institute (2005), and divided them by total population, which we gathered from the World Bank (2007). Arable land refers to land under temporary crops (double-cropped areas are counted only once), temporary meadows for mowing or pasture, land under market and kitchen gardens, and land 30 temporarily fallow (World Resources Institute 2005). Structural human ecology (e.g., York et al. 2003) asserts that including this predictor allows us to control for the extent to which domestic resource availability and / or density influences consumption-based resource demand. We include measures of urban population, which quantifies the percent of a country’s population residing in urban areas. 13 These data are gathered from the World Bank (2007). To test for an environmental Kuznets curve, we include the quadratic of GDP per capita (ln). In an effort to minimize collinearity, we center the measures by subtracting the mean of GDP per capita (ln) before squaring them (Neter, Wasserman, and Kutner 1990). We include two measures of militarization that we gathered from the World Bank (2007): military personnel as percent total population (ln) and military expenditures as percent total GDP (ln). Military personnel are active duty military personnel as well as paramilitary forces if the training, organization, and equipment suggest they may be used to support or replace regular military forces. We obtain overall numbers of military personnel and divide them by total population measures that we gathered from the same source. Military expenditures data include all current and capital expenditures on the armed forces as percent GDP, including peacekeeping forces; defense ministries and other government agencies engaged in defense projects; paramilitary forces, if these are judged to be trained and equipped for military operations; and military space activities. More specifically, such expenditures include operation and maintenance; procurement; military research and development; military and civil personnel, including retirement 31 pensions of military personnel and social services for personnel; and military aid (in the military expenditures of the donor country). Manufacturing as percent total GDP measures the extent to which a nation’s economy is manufacturing-based. These data are obtained from the World Bank (2007). Services as percent total GDP controls for the extent to which the economy within a given nation is services-based. These data are gathered from the World Bank (2007). Besides the majority of predictors already described, in the RE models we include two dummy-coded latitude measures to control for climate conditions: temperate and tropical. Using the same criteria as York et al. (2003), countries where the predominant latitude is less than 30 degrees from the equator are coded as tropical, and countries where the predominant latitude is between 30 and 55 degrees from the equator are coded as temperate. Arctic countries, meaning those where the predominant latitude is greater than 55 degrees from the equator, are the reference category. To investigate the potential impacts of ecologically unequal exchange, in the RE models we include a weighted index (ln) that quantifies the relative extent to which a country’s exports are sent to more-developed countries. The weighted index is referred to as “weighted export flows.” This measure, which was developed by Jorgenson (2006b) to test hypotheses in a cross-national analyses of deforestation, was also recently used in panel analyses of industrial organic water pollution in less-developed countries (Shandra, Shor, and London 2008). Data required for the construction of the index include (1) relational measures in the form of exports between sending and receiving countries, and (2) attributional measures of economic development for receiving countries in the form of GDP per capita. 32 The weighted index is calculated as: N Wi = Σ pijaj j=1 Where: Wi = weighted export flows for country i pij = proportion of country i’s total exports sent to receiving country j aj = GDP per capita of receiving country j The Exports data are taken from the International Monetary Fund’s 2003 Direction of Trade Statistics CD ROM database, and reported in current U.S. dollars. 14 These data include export flows for all commodity types. Per capita GDP data are taken from the World Bank (2007) and are in constant 2000 U.S. dollars. 15 Due to data limitations at the time of the study, the weighted export flows measures are available for every five years from 1975 to 2000 for 58 of the 69 countries included in the current analyses. Hence, the RE models that include this predictor are temporally restricted to the same 6 time points across the 25-year period. In order to assess the theoretically derived notion that the impact of ecologically unequal exchange is more pronounced for less-developed countries than for developed countries, we calculate and use a slope-dummy interaction (Hamilton 1992) between the weighted export flows measures and a dummy-coded variable for less-developed countries. 16 The inclusion of this interaction variable involves a slightly more complex interpretation of the effects. The coefficient for weighted export flows is the unit change in per capita footprints for developed countries (i.e., the reference category) for each unit increase in the former for the same year. The effect of export flows for less-developed countries equals the sum of the coefficients for developed countries and the appropriate 33 interaction term, labeled as “weighted export flows (ln) X LDCs.” The test of statistical significance for the slope-dummy coefficients determines whether the slope for the particular interaction and the reference category—in this case developed countries— differ significantly. Other recent cross-national investigations employ this type of interaction for similar reasons (e.g., Jorgenson and Kuykendall forthcoming; Kick et al. 1996; Rice 2007b). Table 1 provides descriptive statistics and Table 2 presents pairwise bivariate correlations for all variables included in the reported panel analyses. <Table 1 about here> <Table 2 about here> RESULTS AND DISCUSSION Table 3 provides the results of the OLS FE analyses. We report findings for 9 models. Model 1 consists of only per capita GDP. Models 2 through 8 include the predictors in the preceding model as well as one additional independent variable. Model 2 includes per capita GDP as well as arable land per capita. We add urban population in Model 3, and we add the quadratic for per capita GDP in Model 4. Military personnel is added to Model 5, while military expenditures is added to Model 6. We add manufacturing as percent GDP to Model 7, and services as percent GDP to Model 8. Model 9 consists of predictors found to have statistically significant effects on the outcome in any preceding model. 17 For all panel regression analyses, we report unstandardized coefficients, which are flagged for statistical significance. We also report standardized coefficients and robust standard errors for all predictors. For each model, we report values for r-square within, r- 34 square between, and r-square overall, and we also report overall sample sizes, mean observations per country, minimum observations per country, and maximum observations per country. All models presented in Table 3 as well as the RE models in Tables 4 and 5 include unreported period-specific intercepts. <Table 3 about here> Findings for the FE analyses yield multiple theoretically relevant statistical relationships. First, the effect of per capita GDP is positive and remains relatively stable in magnitude across all tested models. Jumping to the quadratic for development, the effect of per capita GDP squared is also positive, and the magnitude of its effect increases with the inclusion of additional predictors in Models 5 through 8. The positive effects of both per capita GDP and its quadratic on the per capita footprints of nations provide strong support for the theoretical traditions that argue that economic growth increases the degradation of nature, particularly treadmill of production, metabolic rift, and worldsystems perspectives. Additionally, these results run counter to key tenets of ecological modernization theory and orientations that predict an environmental Kuznets curve. In a related vein, some evidence is found indicating that more urbanized societies exhibit higher levels of consumption-based environmental demand, lending support for certain premises of the metabolic rift perspective and urban political-economy approaches. More specifically, the effect of urban population is positive and statistically significant in two out of seven models (Models 7 and 8). However, as articulated by multiple theoretical perspectives (e.g., Foster 1999; Molotch 1976) and prior research (e.g., Jorgenson 2003; York et al. 2003), in general, economic development and urbanization are related processes with shared structural conditions. 18 35 Turning to the military, results suggest that it is not the relative size of the military personnel that influences consumption-based environmental demand, but rather, the relative level of capital investment in the form of military expenditures as percent GDP. 19 The positive effect of military expenditures on per capita footprints is statistically significant in 3 out of 4 models (Models 7 through 9). While its relative magnitude is small, the positive effect of military expenditures is consistent with Hooks and Smith’s (2004, 2005) treadmill of destruction theorization as well as the assertions of politicaleconomic sociologists (e.g., Chase-Dunn 1998; Kentor 2000) concerning the enhanced ability of nation-states with more technologically advanced militaries to gain disproportionate access to the global ecosystem’s resource taps and waste sinks (e.g., Podobnik 2006). What is more, the positive effect of military expenditures, net of economic development, underscores that while military institutions and their environmental impacts are connected to economic interests and the treadmill of production’s ecological consequences (Schnaiberg and Gould 2000), they are also somewhat independent of them (Jorgenson 2005; York 2007). Little evidence is found suggesting the importance of domestic economy structure relative to other factors when considering the consumption-based environmental impacts of nations. More directly, the effect of services as percent GDP is non-significant, while the effect of manufacturing as percent GDP is positive yet only statistically significant in one out of three relevant models (Model 7). While these results lend little if any support to arguments posed by neoclassical economic perspectives and more critical politicaleconomic perspectives about the potential environmental impacts of manufacturing-based economies, they also do not provide support for neoclassical economic assertions 36 concerning the likely environmental benefits of more service-based economies. 20 Still, we would not dismiss their potential importance for more particular sorts of environmental degradation (e.g., deforestation) or pollution (e.g., industrial water pollutants, anthropogenic greenhouse gas emissions). Rather, the current findings indicate that other structural factors are more relevant when considering the overall consumption-based environmental impacts of societies, at least in the context of the per capita footprints of nations. Consistent with structural human ecology (e.g., York et al. 2003), biogeography in the context of the local availability of arable land influences the environmental demand posed by the consumption habits of nations. The positive effect of arable land per capita is statistically significant in six out of eight relevant models (Models 4 through 9), while the relative magnitude of its effect is well beyond trivial. Besides validating fundamental principles of human ecology, these findings, coupled with the reported effects of economic development, urbanization, and military expenditures, underscore the importance for considering the relevance of ecological conditions when focusing on the environmental impacts of political-economic factors and other structural conditions. Furthermore, the FE models account for temporally invariant ecological factors, such as latitude. In the subsequent RE analyses, however, we are able to directly assess and compare the relative impacts of latitude to other ecological and structural factors. Table 4 presents the results of GLS RE analyses that focus on the impacts of the factors found to have statistically significant effects in the preceding analyses, while also assessing the effects of latitude. We report the findings for three models. Model 1 consists of per capita GDP, arable land per capita, urban population, the quadratic of 37 GDP per capita, and the two latitude dummy variables: temperate and tropical. Model 2 also includes military expenditures as percent GDP. Model 3 includes only the predictors found to have statistically significant effects in either Model 1 or Model 2. <Table 4 about here> Similar to the FE analyses, the effects of level of development and its quadratic, arable land availability, urban population, and military expenditures are all positive and statistically significant in the RE models. Turning to climate, results indicate that nations closer to the equator do indeed have relatively lower consumption-based environmental impacts than those located in more temperate and arctic climates. In particular, and all else being equal, nations located in tropical climates—meaning those less than 30 degrees from the equator—have relatively lower per capita footprints than nations located further away from the equator. Simply, more resources per person are consumed to sustain societies located in colder climates. Given that the effect of the temperate control is statistically significant in only one of two models (Model 1), and the relative magnitude of its effect in Model 1 is smaller than the tropical control, it appears that the most relevant difference is between tropical and non-tropical nations. In addition to social structural factors, biogeography and climate both play important roles in conditioning the environmental impacts of human activities and their built environments (e.g., Dietz et al. 2007). Table 5 provides findings for the RE analyses that evaluate assertions of ecologically unequal exchange theory. Results of three models are reported. Model 1 includes the weighted export flows index as well as per capita GDP, arable land per capita, urban population, military expenditures as percent GDP, and the tropical dummy- 38 coded measure for latitude. Model 2 includes all predictors in Model 1 as well as the slope-dummy interaction for weighted export flows and less-developed countries. Model 3 is reduced to both weighted export flows measures and other predictors with statistically significant effects in the preceding two models. As discussed above, due to data availability limitations for the weighted exports flows measures, the models presented in Table 5 are limited to the 1975-2000 period for 58 countries, thus reducing the temporal depth and overall sample sizes relative to the analyses presented in the two preceding tables. 21 <Table 5 about here> GDP per capita and arable land per capita both continue to positively affect the consumption-based environmental impacts of nations. 22 However, the effects of urban population, military expenditures, and tropical climate are all non-significant. We speculate that these results, which contradict the preceding analyses, are likely a function of the overall reduced sample sizes, lesser number of countries, and reduced temporal depth for the current models. Turning to the findings of particular interest for this final set of analyses, the effect of weighted export flows is non-significant. However, the slope-dummy interaction between weighted export flows and less-developed countries is negative and statistically significant in both relevant models. To further assess these relationships, elsewhere we include the dummy-coded measure for less-developed countries, which controls for the possibility of differing intercepts (and their potential impacts on the differing slopes of interest) for this group of countries relative to the developed countries. Including the dummy variable does not substantively alter the reported findings concerning the slope-dummy interaction and the main effect for the 39 reference category. We also conduct additional analyses separately for the developed countries and less-developed countries. Consistent with the results presented in Table 5, the effect of weighted export flows is non-significant in the analyses of only the developed countries, but the effect of this predictor is negative and statistically significant in the analyses of only the less-developed countries. The results, particularly the reported negative effect for the interaction between weighted export flows and less-developed countries, support the theory of ecologically unequal exchange (e.g., Bunker 1984; Jorgenson 2006a; Rice 2007a). Due the their structurally advantageous positions in the world economy, the populations of moredeveloped countries are able to secure and maintain favorable terms of trade, which allows for greater access to the sink capacity and natural resource stocks within lessdeveloped countries, which facilitates the externalization of environmental costs of resource consumption. Consequently, these structural relationships suppress resource consumption opportunities for less-developed countries, well below globally sustainable thresholds in many cases. The results lend support to these theoretical articulations, while also taking into account the impacts of other structural factors as well as biogeography. More simply, and taken as a whole, this research indicates that structural relationships between societies (ecologically unequal exchanges), the structural attributes of societies (economic development, military expenditures, urbanization), and the ecological conditions in which societies are located (climate, biogeography) all play important roles in conditioning their consumption-based environmental impacts. 40 CONCLUSION A “human exemptionalist” paradigm—where social processes are treated as independent of the biophysical environment—is untenable within sociology (Dunlap and Catton 1979). While natural scientists emphasize that humans are radically altering the biophysical processes of Earth, too often environmental sociology is marginalized or seen as a quaint realm of inquiry. But the threat of global climate change and other pressing environmental problems (e.g., the collapse of the world’s fisheries, deforestation, water pollution) compels sociology to direct more attention to studying associations between society and nature. Even with the importance of such problems being recognized by scholars across the sciences, environmental sociology still operates from the wings of the discipline to investigate various sorts of society / nature relationships, with growing focus on social structures that influence environmental conditions. At the same time, attention is increasingly paid to how constant as well as changing natural conditions affect the social world. Here, we illuminated how distinct, yet overlapping, theoretical traditions (ecological modernization, treadmill of production, metabolic rift, and world-systems) have developed within environmental sociology. We engaged this rich field, while also including other emerging perspectives (treadmill of destruction, domestic economy structure, ecologically unequal exchange, urban political-economy, and structural human ecology) within it, to explicate the various theoretical arguments in regard to how they understand society / nature connections. From this, we identified a range of social and ecological factors that the various perspectives suggest influence the consumption-based environmental impacts of nations. 41 Findings for the fixed effects and random effects panel regression analyses highlight how there is no basis to remain agnostic about whether or not social processes are tied to the biophysical environment, given that a wide range of variables impact the consumption-based environmental demands of societies, leading to larger per capita ecological footprints. The results lend strong support to the arguments of most of the major theoretical orientations within environmental sociology, which indicates that these positions identify significant human / environment dynamics that deserve attention. Many environmental sociology perspectives focus on the economic dimensions of society / nature relationships. We find that per capita GDP and its quadratic both positively affect consumption-based environmental demands, which are consistent with the treadmill of production, metabolic rift, and world-systems perspectives. All three theoretical traditions argue that economic growth increases the degradation of nature. These results sharply contest key propositions of ecological modernization theory and perspectives that claim the existence of an environmental Kuznets curve in macrocomparative context. Perhaps it is not too surprising that economic operations influence natural conditions, but it is significant to note that expanding economic systems weigh heavily upon nature, regardless of whether an economy is more service-based or manufacturing-based. Thus, affluence and economic growth should continue to be issues of utmost concern when considering the human dimensions of global (and local) environmental change. Consistent with arguments of urban political-economy scholars and the metabolic rift perspective, we find that more urbanized societies have higher levels of consumptionbased environmental impacts. Cities remain centers of growth and demand massive 42 amounts of external resources (often from distant lands) to sustain daily operations. The structural configurations of urban areas establish patterns of consumption that are often only reinforced with the continued expansion of modern cities. The dimensions of these relationships are recognized by the global cities literature, as particular “command points” embody a large degree of control over commodity production and distribution within the world economy. In part, we capture these issues, but at the level of nations, between more- and less-developed countries, in the context of the vertical flow of exports. Environmental space (whether in the form of natural resources or land) in lessdeveloped countries is assimilated into the economies of the more-developed countries. Here our results are consistent with the theory of ecologically unequal exchange, as well as positions taken by both the world-systems and metabolic rift perspectives. While the structure of the global economy influences the distribution of money and commodities between nations, control of and access to the world’s resources remains an important issue, especially for core nations, which sometimes employ their military to secure natural resources. Military expenditures redirect social spending, in part, to sustain and build armed forces. This institution can have a momentum of its own, as far as garnering resources and expansion. Here we find a positive relationship between consumption-based environmental impacts and military expenditures, consistent with the treadmill of destruction theory and other political-economy approaches, including worldsystems analysis. Ironically it seems that military expenditures may often be employed to secure valuable resources, but at the same time, this social structure necessitates the vast consumption of resources, increasing the per capita footprints of nations. 43 Human society is bounded by ecological conditions, which influence the capacity of social institutions to operate as well as the ability of humans to support themselves. While accounting for the role of nature on society can take many forms, here we considered the influence of biogeography and climate. Consistent with the human ecology perspective, we find these ecological conditions to partially shape the resource consumption habits of nations. Questions of environmental sustainability are rooted in concerns for ecological factors, so further consideration of changing natural conditions is an important issue to incorporate into subsequent research—and no doubt such work will demand both quantitative and qualitative approaches. Environmental sociology has made important strides in studying the social structures and conditions that shape the environmental burdens of nations. From our analyses, it is clear that various theoretical perspectives successfully identify structural contributors to environmental degradation—economic development, urbanization, militarization, and ecologically unequal exchange. While there are differences between the perspectives, it is important to note commonalities in their positions. Furthermore, environmental sociology is raising critical questions about the structural organization of nations and the world economy, not to mention how forms of environmental degradation are tied to other sorts of global inequalities. Political-economy perspectives reveal how the dissection of the modern world—which involves the division of both nature and nations—threatens to undo the conditions on which we depend. Such conclusions are echoed by the leading climatologist, James Hansen, who warns that if societies continue to operate “business as usual,” we are ensuring that we will confront further ecological crises with grave implications for all of humanity. The gravity of this issue is evident in 44 the fact that, as we revealed, the majority of nations now have unsustainable levels of consumption-based environmental demand, as determined by per capita footprints relative to the global biocapacity per capita. 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Rosa, and Thomas Dietz. 2003. “Footprints on the Earth: The Environmental Consequences of Modernity.” American Sociological Review 68:279-300. 58 ENDNOTES 1 This branch of environmental economists is more favorable to laissez-faire conservatives than ecological modernization. The latter was constructed on the optimism that evolved out of the social-democratic / welfare capitalism tradition in Europe, and proposes a “rational capitalism” and a degree of state regulation dictated by the market. It proposes a “third way” that avoids a break with the current economic system. 2 The application of artificial fertilizers helps continue production, but does not resolve the metabolic rift. 3 While Hooks and Smith apply their treadmill of destruction theory to the U.S. military and domestic conditions, we situate the orientation in comparative perspective. 4 In the global cities literature, the term “command points” is used to highlight the centrality of key global cities as containers of the headquarters of many of the world’s largest transnational corporations that exercise a relatively large degree of control over global commodity production and distribution (e.g., Sassen 2001). 5 “Producer services” are services for firms, including financial, legal, advertising, consulting, transport, communications, cleaning services, security, and storage. A common argument in the global cities literature is that these producer services are disproportionately concentrated in the largest and most powerful global cities, which tend to be located in more-developed countries (Alderson and Beckfield 2004). 6 In 1965, Georg Borgstrom introduced the concept of “ghost acres” to refer to Britain’s dependence on food and raw materials from colonial and neocolonial hinterlands in order to sustain the productive, consumption, and trade operations of that nation. These ghost acres are analogous to today’s ecological footprint (see Borgstrom 1965). 59 7 Wackernagel and associates have continued to advance the methodology used to calculate ecological footprints (e.g., Global Footprint Network 2006). 8 It is important to recognize that the capacity of a carbon sink to absorb carbon dioxide changes. Recently, scientists have indicated that the decline in the capacity of carbon sinks has contributed to the upswing in carbon accumulation in the atmosphere, at a rate that is stronger, and sooner, than anticipated (Canadell et al. 2007). 9 The analyses are restricted to countries where the ecological footprints contain no temporal anomalies in their calculations as identified by Susannah Buchan, a research associate for the Global Footprint Network. 10 Here, cases refer to the countries included in the current study’s sample. 11 Elsewhere we include a correction for first-order autocorrelation (i.e. AR[1] correction) in all FE and RE models. The results are substantively identical to those reported in the current study and available from the authors upon request. 12 The Global Footprint Network is an international nonprofit organization that works with various partner organizations to coordinate research, develop methodological approaches, and provide resource accounts to help with policy development. Time series datasets of ecological footprints and biocapacity measures are directly available from the Global Footprint Network. 13 Since an increase in the percent of a nation’s population residing in urban areas corresponds with a decrease in the percent of the domestic population residing in rural areas, we only include measures of urban population in the analyses. 14 Due to the calculations involved in creating the weighted index, the use of export flows data reported in current U.S. dollars is not problematic for the panel analyses. 60 15 For a more in-depth discussion of the weighted index, see Jorgenson (2006b). 16 Here, less-developed countries are those in the dataset that fall below the upper quartile of the World Bank’s (2007) income quartile classification of countries (based on level of economic development). Appendix A highlights the countries in the dataset that are classified using the above criteria as less-developed. 17 Elsewhere, we also include measures partially derived from world society theory (e.g., Meyer et al. 1997) in additional panel models. These measures include counts of environmental international non-governmental organizations (EINGO) present in a given country (both weighted and un-weighted by population size) as well as whether or not a nation has an environmental ministry. The effects of the EINGO and environmental ministry measures on per capita footprints are all non-significant, and their inclusion does not substantively alter the reported findings. The EINGO data were analyzed by Smith and Wiest (2005) as an outcome, who we thank for sharing these data with us. We thank David John Frank for the environmental ministry data, which he analyzed as a predictor with coauthors in prior research (Frank, Hironaka, and Schofer 2000). 18 As indicated by Table 2, GDP per capita and urban population as percent total population are also highly correlated, which could partially explain why the effect of urban population is non-significant in many of the reported models. 19 Elsewhere, we employ an additional military predictor: military expenditures per soldier. However, this measure is very highly correlated with per capita GDP (approximately .95). Thus, in these additional analyses we exclude per capita GDP. Upon doing so, the effect of military expenditures per soldier is positive and statistically significant, which corresponds with prior cross-sectional analyses (Jorgenson 2005) as 61 well as the proposed theorization concerning the potential environmental impacts of a more capital intensive and thus more technologically developed military. These additional analyses are available from the authors upon request. 20 In additional unreported analyses we also control for agriculture as percent GDP. The effect of this additional predictor on the outcome is non-significant, and its inclusion does not substantively alter the reported findings. 21 It is important to note that the focus here is on the structure of exports in the context of the vertical flow of exports to more-developed countries, which captures key aspects of ecologically unequal exchange theory. As discussed in preceding sections, levels of exports (and imports) along with levels of production for hundreds of commodity types are used in the calculation of the dependent variable. Thus, the inclusion of exports as percent GDP in models of per capita footprints would be analogous to controlling for the per capita footprint in analyses of per capita carbon dioxide emissions, meaning to some extent the outcome is unintentionally included as a predictor (see Fisher and Freudenburg 2004; York and Rosa 2005). 22 Elsewhere, we also include the quadratic for per capita GDP. The effect of this predictor is positive and statistically significant, and its inclusion does not alter the reported findings of interest, particularly the effects of weighted export flows (nonsignificant) and the slope-dummy interaction for weighted export flows and lessdeveloped countries (statistically significant). These additional analyses are available from the authors upon request. 62 Appendix. Countries Included in the Analyses Albania Algeria*# Angola*# Argentina*# Austria* Belgium* Bosnia & Herzegovina Brazil*# Bulgaria*# Cameroon*# Canada* Central African Republic*# Chad*# China*# Colombia*# Cote Divoire*# Croatia Democratic Republic of Congo*# Egypt*# Estonia Finland* France* Gambia*# Germany* Haiti*# Hungary*# India*# Indonesia*# Iran*# Ireland Italy* Japan* Kenya*# Kuwait Laos*# Latvia Lebanon*# Mali*# Mexico*# Nepal*# Netherlands* Pakistan*# Panama*# Poland*# Portugal* Romania*# Rwanda*# Saudi Arabia Senegal*# South Africa Sudan Sweden* Switzerland* Syria*# Tanzania*# Thailand*# Tunisia*# Turkey*# Turkmenistan Uganda*# United Kingdom* United States of America* Venezuela*# Vietnam*# Yemen Notes: all countries listed are included in the analyses reported in Figure 1, Table 3, and Table 4; starred countries are included in the analyses reported in Table 5; # denotes countries classified as less-developed for the calculation of the slope-dummy interaction variable used in the analyses reported in Table 5 Figure 1 Distance between the Global BioCapacity Per Capita and the Per Capita Footprints of Nations, 1960-2003 Notes: see Appendix A for the list of countries included in the current figure and subsequent panel analyses; zero for the Y axis represents the global biocapacity per capita for the given year indicated by the X axis; negative values on the Y axis correspond with globally sustainable footprint levels, while positive values correspond with globally unsustainable footprint levels Table 1. Descriptive Statistics N Mean Std. Dev. Skewness Min. Max. Ecological Footprint per capita (ln) 543 1.122 .492 .525 .440 2.480 GDP per capita (ln) 543 7.587 1.675 .109 4.440 10.760 Arable Land per capita (ln) 543 .266 .184 1.491 .000 1.150 Urban Population 543 49.119 23.675 .009 2.400 98.260 GDP per capita squared 543 2.799 2.361 .586 .000 10.030 Military Personnel as % total population (ln) 491 .417 .261 .721 .000 1.260 Military Expenditures as % GDP (ln) 412 1.222 .439 .717 .100 3.140 Manufacturing as % GDP 284 15.249 7.651 .723 2.060 41.180 Services as % GDP 284 49.625 13.333 -.161 15.900 78.530 Temperate 543 .510 .500 -.041 .000 1.000 Tropical 543 .425 .495 .303 .000 1.000 Weighted Export Flows (ln) 285 9.384 .301 -.878 8.080 10.070 Weighted Export Flows (ln) X LDCs 285 6.598 4.281 -.892 .000 10.070 Table 2. Pairwise Correlations 1. 2. 3. 4. 5. 6. 7. 8. 9. 10. 11. Ecological Footprint per capita (ln) 1. GDP per capita (ln) 2. .910 Arable Land per capita (ln) 3. .143 -.006 Urban Population 4. .805 .862 .017 GDP per capita squared 5. .257 .119 -.134 -.046 Military Personnel as % total population (ln) 6. .465 .441 -.011 .442 -.174 Military Expenditures as % GDP (ln) 7. .200 .118 -.006 .162 -.021 .536 Manufacturing as % GDP 8. .307 .381 .018 .320 -.133 .089 -.159 Services as % GDP 9. .547 .633 .085 .564 .003 .101 -.162 .254 Temperate 10. .351 .404 -.081 .351 -.068 .425 .096 .419 .254 Tropical 11. -.553 -.556 -.101 -.473 .002 -.478 -.051 -.464 -.374 -.878 Weighted Export Flows (ln) 12. .080 .200 -.108 .216 .061 -.312 -.160 .103 .280 -.055 -.014 Weighted Export Flows (ln) X LDCs 13. -.834 -.820 -.009 -.558 -.624 -.075 -.310 -.377 -.602 -.367 .567 12. -.089 Table 3. Unstandardized Coefficients for the Regression of per capita Ecological Footprints on Selected Independent Variables: Fixed Effects Model Estimates for 2 to 10 Observations on 69 Countries, 1960-2003 Model 1 Model 2 Model 3 Model 4 Model 5 Model 6 Model 7 Model 8 Model 9 GDP per capita (ln) .200*** .207*** .202*** .205*** .189*** .165*** .131*** .131*** .141*** [.674] [.699] [.682] [.692] [.637] [.558] [.444] [.443] [.479] (.014) (.015) (.019) (.017) (.021) (.019) (.030) (.032) (.031) Arable Land per capita (ln) .116 [.043] (.065) Urban Population .169 [.062] (.099) .236* [.087] (.100) .272* [.100] (.134) .324* [.119] (.142) .458* [.168] (.228) .459* [.169] (.232) .484* [.178] (.234) .001 [.040] (.001) .001 [.052] (.001) .002 [.097] (.002) .003 [.145] (.002) .005* [.263] (.002) .005* [.262] (.003) .005 [.255] (.003) GDP per capita squared .030*** .035*** .048*** .052*** .052*** .048*** [.145] [.166] [.229] [.249] [.250] [.230] (.003) (.004) (.004) (.014) (.014) (.014) Military Personnel as % total Population (ln) .008 [.004] (.048) Military Expenditures as % GDP (ln) .020 [.011] (.057) -.078 [-.042] (.069) -.077 [-.042] (.067) .036 [.032] (.022) .060** [.053] (.024) .060* [.053] (.025) .046* [.041] (.023) .003* [.056] (.001) .003 [.055] (.002) .002 [.025] (.002) Manufacturing as % GDP Services as % GDP Constant 2 R Within .001 [.002] (.001) -.393*** -.479*** -.497*** -.634*** -.582*** -.534*** (.109) (.123) (.122) (.102) (.131) (.134) -.529 (.319) -.531 (.326) -.573 (.336) .362 .365 .367 .458 .449 .519 .300 .300 .283 2 .825 .840 .847 .866 .861 .840 .857 .857 .883 2 .828 543 8.4 2 10 .842 543 8.4 2 10 .846 543 8.4 2 10 .880 543 8.4 2 10 .868 491 7.7 2 10 .867 412 6.6 2 10 .860 284 4.9 2 10 .859 284 4.9 2 10 .890 301 5.0 2 10 R Between R Overall N Mean Observations Minimum Observations Maximum Observations Notes: all models include unreported period-specific intercepts; *p<.05 **p<.01 ***p<.001 (two-tailed tests); unstandardized coefficients flagged for statistical significance; standardized coefficients appear in brackets; robust standard errors are in parentheses Table 4. Unstandardized Coefficients for the Regression of per capita Ecological Footprints on Selected Independent Variables: Random Effects Model Estimates for 2 to 10 Observations on 69 Countries, 1960-2003 Model 1 Model 2 Model 3 GDP per capita (ln) .206*** [.703] (.017) .180*** [.606] (.017) .181*** [.610] (.017) Arable Land per capita (ln) .316*** [.118] (.076) .383*** [.141] (.081) .428*** [.158] (.075) .002* [.093] (.001) .003** [.167] (.001) .004*** [.178] (.001) .031*** [.149] (.003) .045*** [.215] (.004) .045*** [.217] (.004) .041* [.036] (.018) .039* [.034] (.018) Urban Population GDP per capita squared Military Expenditures as % GDP (ln) Temperate -.189* [-.192] (.090) -.175 [-.178] (.108) Tropical -.296** [-.298] (.101) -.391** [-.304] (.115) -.140** [-.142] (.054) Constant -.472** (.150) -.450** (.165) -.634*** (.118) 2 R Within .457 .525 .524 2 .890 .881 .874 2 .888 543 8.4 2 10 .888 434 6.9 2 10 .886 434 6.9 2 10 R Between R Overall N Mean Observations Minimum Observations Maximum Observations Notes: all models include unreported period-specific intercepts; *p<.05 **p<.01 ***p<.001 (two-tailed tests); unstandardized coefficients flagged for statistical significance; standardized coefficients appear in brackets; robust standard errors are in parentheses Table 5. Unstandardized Coefficients for the Regression of per capita Ecological Footprints on Selected Independent Variables: Random Effects Model Estimates for 2 to 6 Observations on 58 Countries, 1975-2000 Model 1 Model 2 Model 3 GDP per capita (ln) .238*** [.806] (.021) .187*** [.636] (.023) .206*** [.698] (.018) Arable Land per capita (ln) .397*** [.136] (.089) .426*** [.147] (.077) .352*** [.121] (.074) Urban Population .001 [.034] (.001) .001 [.068] (.001) Military Expenditures as % GDP (ln) .024 [.018] (.023) .018 [.013] (.024) Tropical -.108 [-.105] (.062) -.087 [-.086] (.057) Weighted Export Flows (ln) -.037 [-.023] (.027) -.006 [-.004] (.032) -.001 [-.001] (.026) -.026** [-.215] (.008) -.031*** [-.259] (.008) -.456 (.293) -.233 (.279) -.322 (.169) Weighted Export Flows (ln) X LDCs Constant 2 R Within .301 .312 .305 2 .890 .912 .901 2 .880 236 4.6 2 6 .904 236 4.6 2 6 .902 285 5.4 3 6 R Between R Overall N Mean Observations Minimum Observations Maximum Observations Notes: all models include unreported period-specific intercepts; *p<.05 **p<.01 ***p<.001 (two-tailed tests); unstandardized coefficients flagged for statistical significance; standardized coefficients appear in brackets; robust standard errors are in parentheses