Climate Change, Crop Yields, and Internal Migration in the United States

We investigate the link between agricultural productivity and net migration in the United States using a county-level panel for the most recent period of 1970-2009. In rural counties of the Corn Belt, we find a statistically significant relationship between changes in net outmigration and climate-driven changes in crop yields, with an estimated semi-elasticity of about -0.17, i.e., a 1% decrease in yields leads to a 0.17% net reduction of the population through migration. This effect is primarily driven by young adults. We do not detect a response for senior citizens, nor for the general population in eastern counties outside the Corn Belt. Applying this semi-elasticity to predicted yield changes under the B2 scenario of the Hadley III model, we project that, holding other factors constant, climate change would on average induce 3.7% of the adult population (ages 15-59) to leave rural counties of the Corn Belt in the medium term (2020-2049) compared to the 1960-1989 baseline, with the possibility of a much larger migration response in the long term (2077-2099). Since there is uncertainty about future warming, we also present projections for a range of uniform climate change scenarios in temperature or precipitation.

Reducing Acid Rain in Eastern North America: The Scientific Basis for an Acid Rain Control Policy

This Article presents the scientific basis for an effective acid rain control policy. Part I suggests that if a choice must be made, regulation should focus primarily on sulfur dioxide emissions rather than nitrogen oxide emissions because sulfur deposition is the major cause of watershed acidification. Part II explains the need for at least a fifty percent reduction in sulfur dioxide emissions to meet a safe deposition level. Part III specifies the geographical allocation of sulfur emission reductions necessary to attain target deposition levels in the northeastern United States and southeastern Canada. The Article concludes by demonstrating the need for swift adoption and implementation of an effective acid deposition control strategy in light of large future risks of accumulating irreversible damage

Long-term scenarios for aviation: Demand and emissions of CO\u3csub\u3e2\u3c/sub\u3e and NO\u3csub\u3ex\u3c/sub\u3e

This study presents a dynamical systems model for long-term scenarios of demand in the aviation sector and resultant emissions of CO2 and NOx. We analyze the dynamics of demand growth for aviation, particularly in the emerging markets of developing nations. A model for subsonic aviation emissions is presented that reflects the consequences of industry forecasts for improvement in aviation fuel efficiency and emissions indices as well as projections of global economic and population growth over the next century. (Emissions of commercial supersonic aircraft are not modeled here.) The model incorporates a dynamical system of logistic growth towards a time-dependent capacity level. Using the long-term model, we present a set of projections of demand for aviation services, fossil fuel use, and emissions of carbon dioxide (C02) and nitrogen oxides (NOx through the year 2100; previous forecasts have not extended past 2040. We briefly discuss expectations for the distribution of NOx emissions over altitude and latitude

Aircraft Emissions and the Global Atmosphere

Emissions from airplanes and their potential global effects on the atmosphere have become the subject of intensive study by scientists, and are now drawing the interest of governments. Global fuel consumption has risen much faster for aviation than for other energy-use sectors. Concerns have focused on the contribution of nitrogen oxides (NOx), carbon dioxide (C02), water vapor (H20) and other engine effluents to the buildup of the atmosphere\u27s greenhouse effect. Future aircraft emissions also may affect the stratosphere\u27s ozone layer. This report describes an effort to develop long-term scenarios for emissions from aviation in order to provide a basis for assessing their potential environmental impact throughout the 21st century. Carbon dioxide and nitrogen oxides from the current and projected subsonic aircraft fleets are the main focus of this study. The scenarios in this report were produced by a model that builds on technological and operational assumptions made by industry and government for the period through 2015. It is important to state from the outset what this report is not about. It is not a detailed examination of the environmental effects of aviation. It is not an assessment of the potential for technological or operational changes that could reduce emissions from expected levels. It does not set forth a comprehensive and detailed policy prescription for limiting emissions from aviation. This report does not analyze the potential emissions of a vastly expanded fleet of supersonic aircraft, such as the proposed High-Speed Civil Transport (HSCT), although its possible environmental impacts are discussed briefly

Paris: Beyond the Climate Dead End through Pledge and Review?

"The Paris Climate Agreement of December 2015 marks a decisive break from the unsuccessful Kyoto regime. Instead of targets and timetables, it established a Pledge and Review system, under which states will offer Nationally Determined Contributions (INDCs) to reducing emissions that cause climate change. But this successful negotiation outcome was achieved at the price of vagueness of obligations and substantial discretion for governments. Many governments will be tempted to use the vagueness of the Paris Agreement, and the discretion that it permits, to limit the scope or intensity of their proposed actions. Whether Pledge and Review under the Paris Agreement will lead to effective action against climate change will therefore depend on the inclination both of OECD countries and newly industrializing countries to take costly actions, which for the OECD countries will include financial transfers to their poorer partners. Domestic politics will be crucial in determining the attitudes of both sets of countries to pay such costs. The actual impact of the Paris Agreement will depend on whether it can be used by domestic groups favoring climate action as a point of leverage in domestic politics - that is, in a 'two-level game' simultaneously involving both international and domestic politics." (author's abstract

Rationalising a volcanic crisis through literature: Montserratian verse and the descriptive reconstruction of an island

International audienceThis article discusses a selection of the literary output provoked and inspired by the eruption of Soufrière Hills Volcano on Montserrat - notably poetry and prose written by Montserratians affected by the disaster. It argues that literature can be a source of local knowledge, and a window into a culture that is seeking to deal with a tragedy. It can also be used to assess outreach efforts and to investigate the impact of volcanic events - and of volcanological information - on local populations. The texts describe the process by which Montserratians moved from bewilderment and denial to renewal and re-identification, and even pride in the volcanic activity and their own ability to live with it - and to help prepare other Caribbean islands for future volcanic events. Literature looks both backwards and forwards, communicating the acts of experiencing and changing. On Montserrat, that applies both to colonialism and the role of the UK in Montserrat's political, economic and social life, and also to the importance of learning volcanology, and welcoming volcanologists, as a means of survival

Political legitimacy in decisions about experiments in solar radiation management

Some types of solar radiation management (SRM) research are ethically problematic because they expose persons, animals, and ecosystems to significant risks. In our earlier work, we argued for ethical norms for SRM research based on norms for biomedical research. Biomedical researchers may not conduct research on persons without their consent, but universal consent is impractical for SRM research. We argue that instead of requiring universal consent, ethical norms for SRM research require only political legitimacy in decision-making about global SRM trials. Using Allen Buchanan & Robert Keohane's model of global political legitimacy, we examine several existing global institutions as possible analogues for a politically legitimate SRM decision-making body