Tom Chang, Tal Gross, Joshua Graff Zivin, Matthew Neidell, 15 July 2016

The health effects of pollution in terms of hospitalisations, mortality and morbidity are well researched, but not so much is known about the less severe effects of pollution on workers’ health. This column uses evidence from China to analyse the impact of pollution on productivity, finding that high levels of pollution reduce the productivity even of indoor workers. Reducing pollution is not just welfare-improving for society, it is also of financial benefit to the economy.

Eva Arceo, Rema Hanna, Paulina Oliva, 16 April 2016

Pollution levels are orders of magnitude higher in lower-income countries than in the developed world. This means that studies of the health effects of pollution based on data from the latter will not necessarily be relevant to the former. This column reports on the effect of air pollution on infant mortality in Mexico City. Significant effects are found that are much larger than found in earlier work based on US data. These findings highlight the potential pitfalls of naively extrapolating findings from high-income to developing countries.

Yana Jin, Mu Quan, Chiara Ravetti, Zhang Shiqiu, Timothy Swanson, 02 December 2015

Many cities in China have notoriously high levels of air pollution. Given its tight control over the media, the Chinese government has a high degree of control over public information about air quality. This column explores the government’s incentive to downplay the seriousness of pollution spikes. Households that rely exclusively on public media are found to engage in less self-protective behaviours. This could lead to substantial public health costs in the long run that might otherwise have been avoided.

Ejaz Ghani, Arti Grover Goswami, William Kerr, 18 November 2015

Urbanisation in India is taking many twists and turns. Organised manufacturing is moving out of urban areas, while unorganised manufacturing is transitioning towards urban areas. As the fourth greatest energy consumer in the world, how the country manages this ongoing industrialisation and urbanisation process will have important environmental implications. This column looks at the relationship between growth, geography, and energy efficiency in manufacturing in India. Electricity consumption per unit of output has declined in urban and rural areas, but these overall trends mask substantial variation between states and substantial potential for further efficiency improvements in energy-intensive industries.

Lucas Bretschger, 11 October 2015

There is reasonable hope that the upcoming United Nations Conference on Climate Change in Paris (COP21) will reach a consistent global climate agreement. What makes the negotiations particularly difficult is not economic efficiency, but the equity implications of climate policy. This column presents a framework for incorporating equity concerns into policy design. Building from four equity principles, it reduces the complex problem of international burden sharing to a simple rule tied to a single metric.

Matthew Kahn, Cong Sun, Siqi Zheng, 08 July 2015

China’s cities suffer from extremely high levels of air pollution, and Chinese consumers spend more than $US100 million on anti-smog products per year. Using recent internet sales data, this column explores how investing in such self-protection products varies for consumers with different income brackets. The urban poor are shown to be less likely to engage in this health-improving strategy. This suggests that cross-sectional income comparisons understate lifetime inequality.

Arik Levinson, James O'Brien, 11 March 2015

Rich countries pollute less partly because people in richer countries consume a less pollution-intensive bundle of goods. This column investigates whether this results from consumer preferences or economy-wide changes. Within a country, the environmental Engel curve is concave – meaning that richer households, while polluting more, consume a less pollution-intensive bundle. Over time, this accounts for half of the decrease in rich household pollution, with the remainder being due to price changes and environmental regulations.

Laura Grigolon, Mathias Reynaert, Frank Verboven, 10 January 2015

Using a rich dataset for the European car markets, this column shows that consumers moderately undervalue future fuel costs. This investment inefficiency is too small to justify upfront car taxes to promote fuel efficient cars. A car tax results in a more fuel efficient vehicle fleet than a fuel tax, but fails to induce high-mileage consumers to substitute to more fuel efficient cars. Once we take this targeting effect into account, fuel taxes turn out to be more effective.

Victor Lavy, Avraham Ebenstein, Sefi Roth, 20 November 2014

Admission to higher education often depends on the results of high-stakes tests, but assessing the consequences of having a ‘bad day’ on such tests is challenging. This column provides evidence from a dataset on Israeli high-school students. Random variations in pollution have measurable effects on exam performance, and these in turn have significant effects on students’ future educational and labour-market outcomes. The authors argue that placing too much weight on high-stakes exams may not be consistent with meritocratic principles.

Arik Levinson, 24 September 2014

Pollution emitted by manufacturers has been falling in Europe and the US. A concern with this clean-up is that developed countries have been offshoring the production of pollution-intensive parts and products. This column presents evidence refuting this concern. Using a new approach, the author calculates that almost all of the clean-up in US manufacturing can be explained by technological changes.

Radek Stefanski, 30 May 2014

No comprehensive database of directly measured fossil-fuel subsidies exists at the international or the sub-national level, yet subsidies may be crucial drivers of global carbon emissions. This column describes a novel method for inferring carbon subsidies by examining country-specific patterns in carbon emission-to-output ratios, known as emission intensities. Calculations for 170 nations from 1980-2010 reveal that fossil-fuel price distortions are enormous, increasing, and often hidden. These subsidies contributed importantly to increasing emissions and lower growth.

Richard Tol, 25 April 2014

The IPCC’s Fifth Assessment Report estimates lower costs of climate change and higher costs of abatement than the Stern Review. However, current UN negotiations focus on stabilising atmospheric concentrations of greenhouse gases at even lower levels than recommended by Stern. This column argues that, given realistic estimates of the rate at which people discount the future, the UN’s target is probably too stringent. Moreover, since real-world climate policy is far from the ideal of a uniform carbon price, the costs of emission reduction are likely to be much higher than the IPCC’s estimates.

Lucija Muehlenbachs, Beia Spiller, Christopher Timmins, 09 February 2014

Compared to coal and oil, shale gas offers the prospect of greater energy independence and lower emissions of carbon dioxide and other pollutants. However, fracking is controversial due to the local externalities it creates – particularly because of the potential for groundwater contamination. This column presents evidence on the size of these externalities from a recent study of house prices. The effect attributable to groundwater contamination risk varies from 10% to 22% of the value of the house, depending on its distance from the shale gas well.

Jeffrey Frankel, 27 February 2014

Market-based mechanisms such as cap-and-trade can tackle externality problems more efficiently than command-and-control regulations. However, politicians in the US and Europe have retreated from cap-and-trade in recent years. This column draws a parallel between Republicans’ abandonment of market-based environmental regulation and their recent disavowal of mandatory health insurance. The author argues that in practice, the alternative to market-based regulation is not an absence of regulation, but rather the return of inefficient mandates and subsidies.

Rafael Lalive, Simon Luechinger, Armin Schmutzler, 15 March 2013

Against a backdrop of road accidents, pollution and congestion, many governments subsidise railways with the aim of reducing such externalities. But do improvements in public transport work? This column argues that recent empirical evidence confirms our expectations and, moreover, that public-transport improvements offer good value for money.

Rafael Lalive, Simon Luechinger, Armin Schmutzler, 10 February 2013

Many governments subsidise regional rail service as an alternative to road traffic. This paper assesses whether increases in service frequency reduce road traffic externalities.

Lucija Muehlenbachs, Beia Spiller, Christopher Timmins, 29 September 2012

Natural gas is seen as an attractive source of energy – it is cleaner than coal and often more reliable. But there are potential risks from the drilling and hydraulic fracturing process. This column shows how shale gas extraction could reduce property prices, and argues that policymakers need to bear this in mind when thinking about the costs and benefits.

Jean-Marie Grether, Nicole Mathys, Jaime de Melo, 23 December 2010

Environmentalists have long feared that globalisation will harm the environment by allowing heavily polluting industries to migrate to countries with lax environmental standards. This column presents new evidence from several industries across many countries for all the major pollutants. It suggests that lax policy has only had a small effect on the pollution content of trade.

Matthew Kahn, Siqi Zheng, 14 April 2009

What should China do about its noted pollution problems? This column shows that Chinese cities with less air pollution have higher home prices, suggesting that “green amenities” enter housing prices. Moreover, this marginal valuation of clean air is rising over time. China’s major cities may be becoming cleaner as their inhabitants demand improved environmental conditions.

Judith Dean , Mary Lovely, 14 May 2008

Chinese trade and pollution have exploded over the last decade. But new evidence shows that trade isn’t to blame for the pollution. In fact, Chinese imports and exports are becoming cleaner over time.