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² Neumayer, Eric, ‘Does Trade Openness Promote Multilateral Environmental Cooperation?’ World Economy, 25 (2002), 815–832CrossRefGoogle Scholar; Ward, Hugh, ‘Liberal Democracy and Sustainability’, Environmental Politics, 17 (2008), 386–409CrossRefGoogle Scholar; Baettig, Michèle and Bernauer, Thomas, ‘National Institutions and Global Public Goods: Are Democracies More Cooperative in Climate Change Policy?’ International Organization, 63 (2009), 281–308CrossRefGoogle Scholar.

³ Cf. Neumayer, Eric, ‘Do Democracies Exhibit Stronger International Environmental Commitment? A Cross-Country Analysis’, Journal of Peace Research, 39 (2002), 139–164CrossRefGoogle Scholar; Deacon, Robert T., ‘Dictatorship, Democracy, and the Provision of Public Goods’ (University of California, Santa Barbara, Working Paper, 2003), 1–57Google Scholar.

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¹¹ According to Jon Pevehouse, Timothy Nordstrom and Kevin Warnke, ‘Intergovernmental Organizations. 1815–2000: A New Correlates of War Data Set. Version 2.1’ (2004), an IGO is an organization that consists of at least three members of the COW-defined state system, holds regular plenary sessions at least once every ten years, and possesses a permanent secretariat and corresponding headquarters. According to this definition, IGOs are formalized forms of international co-operation.

¹² Keohane, Robert, After Hegemony: Cooperation and Discord in the World Political Economy (Princeton, N.J.: Princeton University Press, 1984)Google Scholar.

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¹⁴ Although some arguments about the way that IGO membership could serve to increase environmental quality should hold for both industrialized and developing countries alike, this is not the case for all arguments.

¹⁵ Keohane, After Hegemony.

¹⁶ Ward, ‘International Linkages and Environmental Sustainability’; Young, Oran R. and Levy, Marc A., ‘The Effectiveness of International Environmental Regimes’, in Oran R. Young, The Effectiveness of International Environmental Regimes: Causal Connections and Behavioral Mechanisms (Cambridge, Mass.: MIT Press, 1999)Google Scholar.

¹⁷ This trend is also becoming evident in the lending behaviour of major development aid actors such as the World Bank. For example, countries applying for loans with the International Development Association (IDA), which is the part of the World Bank that provides loans to the poorest developing countries, are obliged to provide a National Environmental Action Plan, which outlines a country's major environmental problems and describes solutions to mitigate these problems (see Gutner, Tamar, ‘Explaining the Gaps between Mandate and Performance: Agency Theory and World Bank Environmental Reform’, Global Environmental Politics, 5 (2005), 10–37CrossRefGoogle Scholar.

¹⁸ Cao, Xun, ‘Networks of Intergovernmental Organizations and Convergence in Domestic Economic Policies’, International Studies Quarterly, 53 (2009), 1095–1130CrossRefGoogle Scholar.

¹⁹ Jahn, Detlef, ‘The Impact of Globalization on Comparative Analysis’ (paper presented at the ISA Annual Meeting, New Orleans, 2002), p. 2Google Scholar. This idea is closely related to the concept of issue linkage (Keohane, After Hegemony). In order to achieve co-operation in an environmental issue, benefits in other areas like trade, financial or technological assistance, etc. could be offered to countries that would not be willing to co-operate on environmental issues in general.

²⁰ UNEP, ‘State of the Environment Report: Laos’, http://www.rrcap.unep.org/pub/soe/index.cfm, (2001).

²¹ Porter, Gareth, Welsh Brown, Janet and Chasek, Pamela S., Global Environmental Politics (Boulder, Colo.: Westview Press, 2000)Google Scholar; Dasgupta, Susmita, Laplante, Benoit, Wang, Hua and Wheeler, David, ‘Confronting the Environmental Kuznets Curve’, Journal of Economic Perspectives, 16 (2002), 147–168CrossRefGoogle Scholar.

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²⁵ Boehmer, Charles, Gartzke, Erik and Nordstrom, Timothy, ‘Do Intergovernmental Organizations Promote Peace’, World Politics, 57 (2004), 1–38CrossRefGoogle Scholar, p. 37.

²⁶ Boehmer, Gartzke and Nordstrom, ‘Do Intergovernmental Organizations Promote Peace’, p. 37Google Scholar.

²⁷ Grossman, Gene M. and Krueger, Alan B., ‘Economic Growth and the Environment’, Quarterly Journal of Economics, 110 (1995), 353–377CrossRefGoogle Scholar; Selden, Thomas M. and Song, Daqing, ‘Environmental Quality and Development: Is There a Kuznets Curve for Air Pollution Emissions?’ Journal of Environmental Economics and Management, 27 (1994), 147–162CrossRefGoogle Scholar; Shafik, Nemat and Bandyopadhyay, Sushenjit, ‘Economic Growth and Environmental Quality’ (Working Paper: World Development Report, 1992), 1–55Google Scholar; Hettige, Hemamala, Mani, Muthukumara and Wheeler, David, ‘Indutrial Pollution in Economic Development: Kuznets Revisited’, Journal of Development Economics, 62 (2000), 445–476CrossRefGoogle Scholar; Dasgupta, Laplante, Wang and Wheeler, ‘Confronting the Environmental Kuznets Curve’.

²⁸ A luxury good is a good for which the demand increases with the income level. This implies that at low-income levels the good is usually demanded in small quantities, if at all, whereas its demand increases with growing income.

²⁹ Selden and Song, ‘Environmental Quality and Development’. It is important to note that there exist several studies that criticize the literature on the EKC (Dasgupta, Laplante, Wang and Wheeler, ‘Confronting the Environmental Kuznets Curve’; Stern, David I., ‘The Rise and Fall of the Environmental Kuznets Curve’, World Development, 32 (2004), 1419–1439CrossRefGoogle Scholar; Millimet, Daniel L., List, John A. and Stengos, Thanasis, ‘The Environmental Kuznets Curve: Real Progress or Misspecified Models?’ Review of Economics and Statistics, 85 (2003), 1038–1047CrossRefGoogle Scholar; Perman, Roger and Stern, David I., ‘Evidence from Panel Unit Root and Cointegration Tests that the Environmental Kuznets Curve Does Not Exist’, Australian Journal of Agricultural and Resource Economics, 47 (2003), 325–347CrossRefGoogle Scholar; Shen, Junyi, ‘A Simultaneous Estimation of Environmental Kuznets Curve: Evidence from China’, China Economic Review, 17 (2006), 383–394CrossRefGoogle Scholar; Plassmann, Florenz and Khanna, Neha, ‘Household Income and Pollution: Implications for the Debate About the Environmental Kuznets Curve’, Journal of Environment and Development, 15 (2006), 22–41CrossRefGoogle Scholar). The main criticism is that the inverted U-shaped relationship described by the EKC does not reflect the true relationship between environmental quality and national income for two reasons. First, it does not capture all of the factors important for the relationship between income and pollution. Second, most statistical models are not correctly specified. In contrast to the findings of the EKC, the critics argue that the relationship between income and pollution should be either monotonically increasing for all levels of national income or, in the most optimistic setting, pollution might level off for high income countries but not decline. It is important to note that this criticism does not cut against the predictions of my arguments, since they would only reinforce the positive relationship between national income and pollution, which is proposed in this article.

³⁰ Torras, Mariano and Boyce, James K., ‘Income, Inequality, and Pollution: A Reassessment of the Environmental Kuznets Curve’, Ecological Economics, 25 (1998), 147–160CrossRefGoogle Scholar; Neumayer, ‘Do Democracies Exhibit Stronger International Environmental Commitment?’; Deacon, ‘Dictatorship, Democracy, and the Provision of Public Goods’; Fredriksson, Per G., Neumayer, Eric, Damania, Richard and Gates, Scott, ‘Environmentalism, Democracy, and Pollution Control’, Journal of Environmental Economics and Management, 49 (2005), 343–365CrossRefGoogle Scholar; Ward, ‘Liberal Democracy and Sustainability’; Bernauer, Thomas and Koubi, Vally, ‘Effects of Political Institutions on Air Quality’, Ecological Economics, 68 (2009), 1355–1365CrossRefGoogle Scholar.

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³² Bernauer and Koubi, ‘Effects of Political Institutions on Air Quality’; Smith, Alastair, ‘Pernicious Foreign Aid? A Political Economy of Political Institutions and the Effect of Foreign Aid’, in International Political Economy Society Inaugural Conference, Princeton, 2006)Google Scholar; Bueno de Mesquita et al., The Logic of Political Survival.

³³ Bueno de Mesquita et al., The Logic of Political Survival.

³⁴ As Bueno de Mesquita et al. (The Logic of Political Survival, p. 294) note: once autocratic leaders have survived the first year in office, they usually stay in office for a long period.

³⁵ Congleton, Roger, ‘Political Institutions and Pollution Control’, Review of Economics and Statistics, 74 (1992), 412–421CrossRefGoogle Scholar; Midlarsky, ‘Democracy and the Environment’.

³⁶ Midlarsky, ‘Democracy and the Environment’; Olson, Mancur, The Rise and Decline of Nations (New Haven, Conn.: Yale University Press, 1982)Google Scholar.

³⁷ Rogowski, Ronald, ‘International Capital Mobility and National Policy Divergence’, in Miles Kahler and David A. Lake, eds, Governance in a Global Economy: Political Authority in Transition (Princeton, N.J.: Princeton University Press, 2003), pp. 355–374Google Scholar.

³⁸ Neumayer, , ‘Do Democracies Exhibit Stronger International Environmental Commitment?’, p. 150Google Scholar.

³⁹ See: http://data.worldbank.org/about/country-classifications.

⁴⁰ The World Bank calculates annual gross national income (GNI) per capita levels using its Atlas method to diminish the impact that exchange rate fluctuations have on the cross-country comparison of national incomes.

⁴¹ Grossman and Krueger, ‘Economic Growth and the Environment’.

⁴² Sigman, Hilary, ‘International Spillovers and Water Quality in Rivers: Do Countries Free Ride?’ American Economic Review, 92 (2002), 1152–1159CrossRefGoogle Scholar.

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⁴⁴ Data on water quality, on biological oxygen demand in particular, also exist in time-series format. However, availability of the data limits the time frame to 1980–2000, which makes a comparison with the results of this analysis somewhat difficult. The main results, however, do not change when using Biological Oxygen Demand instead of SO₂ or CO₂ emissions and are available upon request. Furthermore, although there are environmental performance indices, their use for time-series cross-section analysis is limited. For example, the composition of the environmental sustainability index changes from year to year, rendering it non-valuable for time-series analysis. Moreover, the concept of genuine savings intends to measure the true rate of savings in an economy after taking into account investments in human capital, depletion of natural resources and damage caused by pollution. Although it can be seen as a measure of weak sustainability (De Soysa and Neumayer, ‘False Prophet, or Genuine Savior?’), its environmental component is very small, implying that genuine savings are not a valuable indicator of environmental performance per se.

⁴⁵ Stern, David I., ‘Global Sulfur Emissions from 1850 to 2000’, Chemosphere, 58 (2005), 163–175CrossRefGoogle Scholar.

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⁴⁷ World Bank, ‘World Development Indicators’.

⁴⁸ World Bank, ‘World Development Indicators’.

⁴⁹ Pevehouse, Nordstrom and Warnke, ‘Intergovernmental Organizations, 1815–2000’.

⁵⁰ Boehmer, Gartzke and Nordstrom, ‘Do Intergovernmental Organizations Promote Peace?’

⁵¹ Boehmer, Gartzke and Nordstrom, ‘Do Intergovernmental Organizations Promote Peace?’

⁵² Boehmer, Gartzke and Nordstrom, ‘Do Intergovernmental Organizations Promote Peace?’ p. 37Google Scholar.

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⁵⁴ Boehmer, Gartzke and Nordstrom, ‘Do Intergovernmental Organizations Promote Peace?’ p. 38Google Scholar.

⁵⁵ Monty G. Marshall and Keith Jaggers, ‘Polity IV Project: Political Regime Characteristics and Transitions, 1800–2002’. The original Polity IV score ranges from -10 (most autocratic) to +10 (most democratic). To facilitate interpretation, the variable is transformed to be positive throughout its complete range. This innocuous change does not affect the results.

⁵⁶ Munck, Gerardo L. and Verkuilen, Jay, ‘Conceptualizing and Measuring Democracy’, Comparative Political Studies, 35 (2002), 5–34Google Scholar.

⁵⁷ Alvarez, Michael, Cheibub, José Antonio, Limongi, Fernando and Przeworski, Adam, ‘Classifying Political Regimes’, Studies in Comparative International Development, 31 (1996), 1–37CrossRefGoogle Scholar.

⁵⁸ Bueno de Mesquita, Smith, Siverson and Morrow, The Logic of Political Survival.

⁵⁹ Results are available from the author upon request.

⁶⁰ Estimating a quadratic model of GDP per capita on environmental performance using all countries’ yields to a turning point of $23,192 in the case of SO₂ and to a turning point that is out of sample in the case of CO₂.

⁶¹ Skrede Gleditsch, Kristian, ‘Expanded Trade and GDP Data’, Journal of Conflict Resolution, 46 (2002), 712–724CrossRefGoogle Scholar.

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⁶³ Frankel and Rose, ‘Is Trade Good or Bad for the Environment?’

⁶⁴ Frankel and Rose, ‘Is Trade Good or Bad for the Environment?’; Antweiler, Copeland and Taylor, ‘Is Free Trade Good for the Environment?’

⁶⁵ Zarsky, L., ‘Havens, Halos and Spaghetti: Untangling the Evidence about Foreign Direct Investment and the Environment’ (OECD Conference on Foreign Direct Investment and the Environment, The Hague, 1999)Google Scholar.

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⁶⁷ Gleditsch, ‘Expanded Trade and GDP Data’.

⁶⁸ However, results do not change if contemporaneous variables are used. In contrast, some results are even more significant. Consequently, using a one-year time lag of all of the independent and control variables seems to be a more conservative approach. Results using contemporaneous variables are available upon request.

⁶⁹ Since the dependent variable is pollution emissions, a negative coefficient sign implies a reduction in emissions and therefore an increase in environmental quality.

⁷⁰ Ingram, Robinson and Bush, ‘The Intergovernmental Network of World Trade’.

⁷¹ Ingram, Robinson and Bush, ‘The Intergovernmental Network of World Trade’.

⁷² African Union, ‘African Union in a Nutshell’, http://au.int/en/about/nutshell (2009); African Union, ‘Capacity Building for an Africa-Wide Biosafety System’, http://www.africa-union.org/root/au/AUC/Departments/HRST/biosafety/AU_Biosafety_1b.htm, (2009).

⁷³ The Cartagena Protocol ‘seeks to protect biological diversity from the potential risks posed by living modified organisms resulting from modern biotechnology’ (ConventiononBiologicalDiversity, ‘Cartagena Protocol on Biosafety’, http://www.cbd.int/biosafety/background.shtml, 2009).

⁷⁴ Cao, ‘Networks of Intergovernmental Organizations and Convergence in Domestic Economic Policies’; Simmons, Beth A. and Elkins, Zachary, ‘The Globalization of Liberalization: Policy Diffusion in the International Political Economy’, American Journal of Political Science, 98 (2004), 171–188CrossRefGoogle Scholar.

⁷⁵ WHO, ‘Public Health and Environment (PHE)’, (2009), http://www.who.int/phe/en/.

⁷⁶ UNIDO, ‘Energy and Environment’, http://www.unido.org/index.php?id=905 (2009).

⁷⁷ IAEA, ‘Pillars of Nuclear Cooperation’, http://www.iaea.org/OurWork/ST/index.html (2009).

⁷⁸ IAEA, ‘National Projects’, http://www.iaea.org/OurWork/ST/index.html (2009). Of course, it is also important to note that nuclear IGOs such as IAEA or the Latin American Energy Organization (OLADE) mostly promote the use of nuclear energy production. By relying on nuclear energy production instead of energy production based on fossil fuels, countries that opt for nuclear energy production emit less SO₂ and CO₂. However, this does not reflect the fact that nuclear energy production produces nuclear waste, which itself constitutes a major environmental problem.

⁷⁹ It is, however, important to note that this result does not necessarily imply that environmental regimes in general are ineffective. In the present analysis only those regimes that are considered to be an international organization are included, implying that they need to possess an international secretariat. This is only true for a very limited number and for only a very specific set of environmental regimes. For example, the set of environmental IGOs includes organizations such as the International Commission of the Northwest Atlantic Fisheries, now called the Northwest Atlantic Fisheries Organization; the International Whaling Commission; the Joint Anti-Locust and Anti-Aviarian Organization, which aims to control the damage arising from locust and aviarian pests; the International Seabed Authority, which regulates deep seabed mining and aims to protect the marine environment; or Bionet, whose purpose it is to classify natural species. Many of these organizations, however, pursue goals such as combating locust pests in Africa that are not related to any of the measures of environmental quality used in this analysis. Hence, even if these organizations were effective for the purpose for which they were created, they would not affect air quality or greenhouse gas emissions because of their specialization. In contrast, other important environmental regimes such as the Convention on Long-Range Transboundary Air Pollution are not included in this sample because they are not considered to be an international organization. Therefore, the results of this analysis cannot be interpreted as evidence against the effectiveness of environmental regimes in general.

⁸⁰ Pevehouse, Nordstrom and Warnke, ‘Intergovernmental Organizations, 1815–2000: A New Correlates of War Data Set. Version 2.1’.

⁸¹ Alvarez, Cheibub, Limongi and Przeworski, ‘Classifying Political Regimes’.

⁸² Bueno de Mesquita, Smith, Siverson and Morrow, The Logic of Political Survival.

⁸³ Cao, ‘Networks of Intergovernmental Organizations and Convergence in Domestic Economic Policies’; Simmons and Elkins, ‘The Globalization of Liberalization: Policy Diffusion in the International Political Economy’.

⁸⁴ Antweiler, Copeland and Taylor, ‘Is Free Trade Good for the Environment?’; Mani and Wheeler, ‘In Search of Pollution Havens?’

⁸⁵ Neumayer, ‘Do Democracies Exhibit Stronger International Environmental Commitment?’; Deacon, ‘Dictatorship, Democracy, and the Provision of Public Goods’.