In this paper, we take a global view at air pollution looking at cities and countries worldwide. We pay special attention at the spatial distribution of population and its relationship with the evolution of emissions. To do so, we build i) a unique and large dataset for more than 1200 (big) cities around the world, combining data on emissions of CO2 and PM2.5 with satellite data on built-up areas, population and light intensity at night at the grid-cell level for the last two decades, and ii) a large dataset for more than 190 countries with data from 1960 to 2010. At the city level, we find that denser cities show lower emissions per capita. We also find evidence for the importance of the spatial structure of the city, with polycentricity being associated with lower emissions in the largest urban areas, while monocentricity being more beneficial for smaller cities. In sum, our results suggest that the size and structure of urban areas matters when studying the density-emissions relationship. This is reinforced by results using our country-level data where we find that higher density in urban areas is associated with lower emissions per capita. All our main findings are robust to several controls and different specifications and estimation techniques, as well as different identification strategies.
In this paper, we present a simple theoretical extension from the Economic Geography literature to characterize the main features of pollution havens (lax environmental regulation, good market access to high-income countries and corruption opportunities). Using structural and reduced-form estimations, we find that pollution havens are not a “popular myth” for European firms, laxer environmental standards significantly explain the location choice of polluting affiliates. We analyze in depth the role of trade costs (using various bilateral and multilateral measures), a 1% increase in access to the European market from a pollution haven fosters relocation there by 0.1%. We also find that corruption lowers environmental standards, which strongly attract polluting firms: a 1% increase of corruption fuels relocation by 0.28%. We test the economic significance of these empirical findings via simulations. The protection of the European market (e.g., a carbon tax on imports) to stop relocations to pollution havens must be high (a decrease of the European market for Morocco and Tunisia equivalent to 13%) not to say prohibitive (31% for China).
This study is a theoretical and empirical analysis of the effects of regional trade integration on the spatial distribution of skills. We first develop a theoretical model in the economic geography field to integrate heterogeneous workers, housing, local entrepreneurs and skill upgrading by unskilled workers. We then analyse how the domestic integration of each state in the USA, approximated by truck registrations, influenced the location choice of skilled and unskilled workers in 1940–1960. By using inter- and intrastate trade flow from the US Commodity Flow Survey, we also analyse the impact of regional trade costs for the contemporary period (1997, 2002, 2007). The theoretical model shows that the bell-shaped curve of spatial development displays a sorting of individuals and firms. Only high-skilled workers increasingly choose the core region during the process of regional integration, while intermediate-skilled workers move to the periphery due to the increase in the price of housing. By impacting differently on the opportunity cost to invest in skill acquisition in the core and the periphery, this sorting influences the regional creation of human capital. First a regional divergence in education investment occurs and then a convergence, but only for high-level regional integration. The empirical analysis confirms that regional trade integration has been a determinant of the spatial distribution of skills in the USA.
This paper examines the potential benefits and costs of providing duty-free-quota-free market access to the least developed countries and the effects of extending eligibility to other poor countries. Using the MIRAGE computable general equilibrium model, it assesses the impact of scenario involving different levels of product coverage, recipient countries, and preference-giving countries. The main goals of this paper is to highlight the role that rich and emerging countries could play in helping poor countries, to assess the costs and benefits for developing countries and whether the potential costs for domestic producers are in line with political feasibility in preference-giving countries.
We document the emergence of spatial polarisation in the United States during the 1980–2008 period. This phenomenon is characterised by stronger employment polarisation in larger cities, both at the occupational and the worker levels. We quantitatively evaluate the role of technology in generating these patterns by constructing and calibrating a spatial equilibrium model. We find that faster skill-biased technological change in larger cities can account for a substantial fraction of spatial polarisation in the United States. Counterfactual exercises suggest that the differential increase in the share of low-skilled workers across city size is due mainly to the large demand by high-skilled workers for low-skilled services and, to a smaller extent, to the higher complementarity between low- and high-skilled workers in production relative to middle-skilled workers.