This issue of Environment includes three articles that, while diverse, each represent next-generation analyses—focusing our attention more precisely and productively, alerting us to profound dangers occluded by prior research, and opening new vistas of climate solutions.
In their article “The Hidden Asthma Epidemic in Immigrant Subpopulations,” Laura Corlin and Doug Brugge help us understand the widespread impacts that asthma has on American society and especially on vulnerable communities. As they report, more than 13% of Americans suffer from asthma, costing the nation more than $60 billion in 2007 alone. Asthma especially affects minorities and the poor, due to increased exposure to indoor and outdoor air pollution, noxious land uses, and mold, among other factors. But recent research has found that these impacts also vary widely within these communities, leading to what is called “the Latino Paradox.” Foreign-born Latinos are much less susceptible to asthma than U.S.-born Latinos, strongly indicating that there are substantial environmental differences between the United States and origin countries. Likewise, there are also substantial differences in asthma rates in immigrants from different countries. Thus, anti-asthma campaigns need to become more sophisticated, targeting the distinct subgroups within racial and ethnic communities that account for the majority of cases.
In his article “Climate Change Mitigation as Catastrophic Risk Management,” Simon Dietz reviews how economists have assessed the costs and benefits of climate policy and how attention has recently shifted from arguments over discount rates to a focus on “fat-tail risks”—the relatively small but substantial risk of catastrophic climate change impacts. He reviews the findings of the famous Stern Review on the economics of climate change, which estimated that if the world continues along current emissions trajectories, climate change could cost from 5 to 20% of global gross domestic product (GDP), while taking action to stabilize atmospheric concentrations at 550 ppm would cost only about 1% of global GDP. This report sparked a robust debate, with much attention focused on Stern's choice of discount rate in his analysis as he used an unusually low rate, which greatly increased his cost estimates. But this debate occluded another critical issue, the existence of “fat tails” in the distribution of climate change outcomes (that is, the relatively small but substantial chance of catastrophic climate impacts, due to a potentially much greater sensitivity of the climate to a doubling of carbon dioxide). For example, the Intergovernmental Panel on Climate Change (IPCC) estimated that there is a 66% chance that the world will warm 1.5 to 4.5°C from a mere doubling of carbon dioxide. Critically, however, there is a 10% chance that the world could warm more than 6°C, perhaps up to 10°C or more. Thus, there is a relatively low but substantial risk of catastrophic consequences. This observation shifts the focus from estimates of the most likely costs to an explicit risk-management frame. Modern societies have developed diverse tools and institutions to hedge against risk, including insurance; thus, we would be wise to hedge our bets. But arguably, this risk is particularly severe. By analogy, if 1 out of every 10 airplanes crashed upon takeoff, killing many on board, most people would refuse to fly. Yet we currently are tampering with the control systems of the one plane(t) we have and there's no getting off.
Finally, in their article on “Building-Integrated Photovoltaics,” Owen Temby and colleagues introduce us to innovative solutions to both reduce carbon emissions and increase local resilience to climate and other shocks. The exponential growth of the solar panel market is one of the great stories of our time, disrupting static business models and democratizing energy production. But photovoltaics (PV) are now also being integrated directly into building materials, enabling a revolution in building design, as well as energy production. As the authors describe, PV can now be integrated into shingles, walls, and glass—enabling retrofits without changing the character of existing buildings, as well as new designs that take advantage of these materials, which are often of higher quality and more cost-competitive than existing materials. But the authors encourage us to think even more deeply about integrative designs that not only generate electricity but also harness the thermal energy created as these building materials absorb heat from the sun. Thus, buildings can create electricity, provide heat, and cool themselves to maintain power production efficiency, all at the same time. Given the enormous amount of building stock about to be built in the developing world, there are immense opportunities to scale these innovations. Together, these articles help us better understand the risks we face, while also pointing to the future we want.