A hipótese da curva de kuznets ambiental global e o protocolo de Quioto

Abstract

Over the years environmental issues have been playing a remarkable role in the global debate about the Earth future. Due to the release of huge amounts of CO2 in the combustion of fossil fuels, its emissions are classified as one of the driving forces behind the global warming phenomenon. Worldwide, emissions of the "greenhouse effect" gases (GHG) are increasing, despite the joint efforts to implement international agreements like the Kyoto Protocol. In this context, the present dissertation is aimed at investigating the Global Environmental Kuznets Curve (EKC) hypothesis and its relationship with the Kyoto Protocol. Therefore, one of its objectives is to verify whether there is an inverted U shaped relationship between an index of global environmental degradation (per capita CO2 emissions) and economic growth (measured by per capita GDP) for a sample of 167 countries over the period 2000-2004, using a fixed effect model with spatial dependence. Another objective of this dissertation is to evaluate the role of the Kyoto Protocol as a global policy in order to reduce emissions. To do so, a dummy variable, representing the countries that have ratified the Protocol, is put in right hand of the regression. Besides, another three variables are inserted in the right hand of regression: the trade level, energy consumption and population density. The findings from Exploratory Spatial Data Analysis (ESDA) revealed that per capita CO2 emissions are not randomly distributed, as well as identified a number of countries that emit more than the other countries, namely, United States, Canada, Australia, Bahrain, Brunei, Kuwait, Luxembourg, United Arab Emirates, Trinidad and Tobago and Aruba. The ESDA analysis found the existence of clusters, showing that the low-low pattern occurs mainly in the poorest countries Asian and African, whereas the High High pattern appears mainly in European countries and countries in Southeast Asia. The econometric results, in principle, suggest the existence of a CKA in the form of "N" rather than "U" inverted, finding the following "turning points": US$ 12,262.44 and US$ 27,083.33. The other explanatory variables also showed the expected signs and all exhibited a highly significant coefficient. Around 80% of the sample did not have income above the “turning point” calculated, that is, the vast majority of countries are in the first upward part curve, revealing that in the range of income observed for the 167 countries, many have a curve monotonically increasing. This seems to confirm and illustrate the global nature of the carbon dioxide impact, revealing that there is little incentive for nations takes unilateral actions to reduce their emissions, as well as multilateral actions are being developed slowly. Another important issue is the negative coefficient, and statistically significant, for the dummy variables of the countries that have ratified the Kyoto Protocol, showing the importance of international agreements on reducing the overall amount of per capita carbon emission. Therefore, economic growth alone cannot replace policies that aspire to reducing CO2 emissions. This result suggests that international policies can help reduce GHG emissions, but we need more countries to commit such reduction. Therefore, economic growth alone does not guarantee a cure for the problems related to the environment. Environmental policies have key role in reversing the trajectory of pollutants that follow the CKA.