Powerful
Dora Costa & Matthew Kahn
Journal of the European Economic Association, June 2013, Pages 680-702
Abstract:
"Nudges" are being widely promoted to encourage energy conservation. We show that the popular electricity conservation "nudge" of providing feedback to households on own and peers' home electricity usage in a home electricity report is two to four times more effective with political liberals than with conservatives. Political conservatives are more likely than liberals to opt out of receiving the home electricity report and to report disliking the report. Our results suggest that energy conservation nudges need to be targeted to be most effective.
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California Energy Efficiency: Lessons for the Rest of the World, or Not?
Arik Levinson
NBER Working Paper, June 2013
Abstract:
Starting in the 1970s California's residential electricity consumption per capita stopped increasing, while other states' electricity use continued to grow steadily. Similar patterns can be seen in non-electric energy, industry, and transportation. What accounts for California's apparent energy savings? Some credit the strict energy efficiency standards for buildings and appliances enacted by California in the mid-1970s. They argue that other states and countries could replicate California's gains, and that California should build on its own success by tightening those standards further. Skeptics might point to three long-run trends that differentiate California's electricity demand from other states: (1) shifting of the U.S. population towards warmer climates of the South and West; (2) relatively small income elasticity of energy demand in California's temperate climate; and (3) evolving differences between the demographics of households in California and other states. Together, these trends account for around 90 percent of California's apparent residential electricity savings, thus providing no lessons for other states or countries considering adopting or tightening their energy efficiency standards.
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Environmental Consequences of the Desire to Dominate and Be Superior
Taciano Milfont et al.
Personality and Social Psychology Bulletin, forthcoming
Abstract:
A belief in human dominance over nature lies at the heart of current environmental problems. In this article, we extend the theoretical scope of social dominance theory by arguing that social dominance orientation (SDO) is an important variable in understanding person-environment relations. We argue that individuals high in SDO are more willing to exploit the environment in unsustainable ways because SDO promotes human hierarchical dominance over nature. Four studies provide support for this perspective. High SDO was associated with lower levels of environmental concern in a nationally representative New Zealand sample (Study 1) and in country-level data across 27 nations (Study 2). SDO was also positively related to utilization attitudes toward nature (Study 3) and mediated the gender difference in beliefs about anthropogenic climate change (Study 4), and both occurred independently of right-wing authoritarianism. Implications for the human-dominated view of nature subscribed to by those high in SDO are discussed.
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Regional variations in the health, environmental, and climate benefits of wind and solar generation
Kyle Siler-Evans et al.
Proceedings of the National Academy of Sciences, forthcoming
Abstract:
When wind or solar energy displace conventional generation, the reduction in emissions varies dramatically across the United States. Although the Southwest has the greatest solar resource, a solar panel in New Jersey displaces significantly more sulfur dioxide, nitrogen oxides, and particulate matter than a panel in Arizona, resulting in 15 times more health and environmental benefits. A wind turbine in West Virginia displaces twice as much carbon dioxide as the same turbine in California. Depending on location, we estimate that the combined health, environmental, and climate benefits from wind or solar range from $10/MWh to $100/MWh, and the sites with the highest energy output do not yield the greatest social benefits in many cases. We estimate that the social benefits from existing wind farms are roughly 60% higher than the cost of the Production Tax Credit, an important federal subsidy for wind energy. However, that same investment could achieve greater health, environmental, and climate benefits if it were differentiated by region.
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The 1970 Clean Air Act and termination of rainfall suppression in a U.S. urban area
Jeremy Diem
Atmospheric Environment, August 2013, Pages 141-146
Abstract:
The purpose of this paper is to determine the impact of reduced atmospheric particulate resulting from the Clean Air Act of 1970 on changes in summer rainfall in the Atlanta, Georgia USA region. In order to determine if rainfall at nine candidate stations in the metropolitan area was influenced by changes in particulate concentrations within the 1948-2009 period, predicted rainfall characteristics were derived from rainfall frequencies at nine reference stations located more than 80 km from downtown Atlanta. Both parametric and non-parametric tests were used to test for significant differences between observed values and predicted values within 34 overlapping 30-year periods. For the country as a whole, emissions of PM10 (i.e. particulates with a diameter less than or equal to 10 μm) decreased by approximately 40% from 1970 to 1975. The reduction in emissions caused a rapid rebound in summer rainfall in the Atlanta region. There was suppression of rainfall over and downwind of the Atlanta urbanized area during 30-yr periods that comprise all or portions of the decades of the 1950s, 1960s, and 1970s. This suppression occurred even while urban-related factors that promote rainfall enhancement were present. During the 1948-1977 suppression period, there was a decrease in rainfall of at least 40 mm at affected locales, which is substantial given that the mean seasonal rainfall was approximately 300 mm. The rainfall suppression involved a decrease of heavy-rainfall days. Atlanta is most likely not a unique case; therefore, particulate-induced rainfall suppression might have occurred over and downwind of other U.S. urban areas prior to the late 1970s.
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Aircraft Noise, Health, and Residential Sorting: Evidence from Two Quasi-Experiments
Stefan Boes, Stephan Nüesch & Steven Stillman
Health Economics, forthcoming
Abstract:
We explore two unexpected changes in flight regulations to estimate the causal effect of aircraft noise on health. Detailed measures of noise are linked with longitudinal data on individual health outcomes based on the exact address information. Controlling for individual heterogeneity and spatial sorting into different neighborhoods, we find that aircraft noise significantly increases sleeping problems and headaches. Models that do not control for such heterogeneity and sorting substantially underestimate the negative health effects, which suggests that individuals self-select into residence based on their unobserved sensitivity to noise. Our study demonstrates that the combination of quasi-experimental variation and panel data is very powerful for identifying causal effects in epidemiological field studies.
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Yuyu Chen et al.
Proceedings of the National Academy of Sciences, forthcoming
Abstract:
This paper's findings suggest that an arbitrary Chinese policy that greatly increases total suspended particulates (TSPs) air pollution is causing the 500 million residents of Northern China to lose more than 2.5 billion life years of life expectancy. The quasi-experimental empirical approach is based on China's Huai River policy, which provided free winter heating via the provision of coal for boilers in cities north of the Huai River but denied heat to the south. Using a regression discontinuity design based on distance from the Huai River, we find that ambient concentrations of TSPs are about 184 μg/m3 [95% confidence interval (CI): 61, 307] or 55% higher in the north. Further, the results indicate that life expectancies are about 5.5 y (95% CI: 0.8, 10.2) lower in the north owing to an increased incidence of cardiorespiratory mortality. More generally, the analysis suggests that long-term exposure to an additional 100 μg/m3 of TSPs is associated with a reduction in life expectancy at birth of about 3.0 y (95% CI: 0.4, 5.6).
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Andrea Roberts et al.
Environmental Health Perspectives, forthcoming
Objective: Air pollution contains many toxicants known to affect neurological function and to have effects on the fetus in utero. Recent studies have reported associations between perinatal exposure to air pollutants and autism spectrum disorder (ASD) in children. We tested the hypothesis that perinatal exposure to air pollutants is associated with ASD, focusing on pollutants associated with ASD in prior studies.
Methods: We estimated associations between U.S. Environmental Protection Agency modeled levels of hazardous air pollutants at the time and place of birth and ASD in the children of participants in the Nurses' Health Study II (325 cases, 22,101 controls). Our analyses focused on pollutants associated with ASD in prior research. We accounted for possible confounding and ascertainment bias by adjusting for family-level socioeconomic status (maternal grandparents' education) and census-tract-level socioeconomic measures (e.g., tract median income and percent college educated), as well as maternal age at birth and year of birth. We also examined possible differences in the relationship between ASD and pollutant exposures by child's sex.
Results: Perinatal exposures to the highest versus lowest quintile of diesel, lead, manganese, mercury, methylene chloride, and an overall measure of metals were significantly associated with ASD, with odds ratios ranging from 1.5 (for overall metals measure) to 2.0 (for diesel and mercury). In addition, linear trends were positive and statistically significant for these exposures (P < .05 for each). For most pollutants, associations were stronger for boys (279 cases) than girls (46 cases) and significantly different according to sex.
Conclusions: Perinatal exposure to air pollutants may increase risk for ASD. Additionally, future studies should consider sex-specific biological pathways connecting perinatal exposure to pollutants with ASD.
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Early Life Air Pollution and Asthma Risk in Minority Children: The GALA II & SAGE II Studies
Katherine Nishimura et al.
American Journal of Respiratory and Critical Care Medicine, forthcoming
Objectives: To assess a causal relationship between air pollution and childhood asthma using data that address temporality by estimating air pollution exposures prior to the development of asthma and to establish the generalizability of the association by studying diverse racial/ethnic populations in different geographic regions.
Methods: This study included Latino (n= 3,343) and African American (n= 977) participants with and without asthma from five urban regions in the mainland U.S. and Puerto Rico. Residential history and data from local ambient air monitoring stations were used to estimate average annual exposure to five air pollutants: ozone (O3), nitrogen dioxide (NO2), sulfur dioxide (SO2), particulate matter ≤ 10µm and ≤ 2.5µm (PM10 and PM2.5). Within each region, we performed logistic regression to determine the relationship between early life exposure to air pollutants and subsequent asthma diagnosis. A random-effects model was used to combine the region-specific effects and generate summary odds ratios (OR) for each pollutant.
Results: After adjustment for confounders, a 5 ppb increase in average NO2 during the first year of life was associated with an OR of 1.17 for physician-diagnosed asthma (95% confidence interval, 1.04-1.31).
Conclusions: Early life NO2 exposure is associated with childhood asthma in Latino and African Americans. These results add to a growing body of evidence that traffic-related pollutants may be causally related to childhood asthma.
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Robert Jackson et al.
Proceedings of the National Academy of Sciences, 9 July 2013, Pages 11250-11255
Abstract:
Horizontal drilling and hydraulic fracturing are transforming energy production, but their potential environmental effects remain controversial. We analyzed 141 drinking water wells across the Appalachian Plateaus physiographic province of northeastern Pennsylvania, examining natural gas concentrations and isotopic signatures with proximity to shale gas wells. Methane was detected in 82% of drinking water samples, with average concentrations six times higher for homes <1 km from natural gas wells (P = 0.0006). Ethane was 23 times higher in homes <1 km from gas wells (P = 0.0013); propane was detected in 10 water wells, all within approximately 1 km distance (P = 0.01). Of three factors previously proposed to influence gas concentrations in shallow groundwater (distances to gas wells, valley bottoms, and the Appalachian Structural Front, a proxy for tectonic deformation), distance to gas wells was highly significant for methane concentrations (P = 0.007; multiple regression), whereas distances to valley bottoms and the Appalachian Structural Front were not significant (P = 0.27 and P = 0.11, respectively). Distance to gas wells was also the most significant factor for Pearson and Spearman correlation analyses (P < 0.01). For ethane concentrations, distance to gas wells was the only statistically significant factor (P < 0.005). Isotopic signatures (δ13C-CH4, δ13C-C2H6, and δ2H-CH4), hydrocarbon ratios (methane to ethane and propane), and the ratio of the noble gas 4He to CH4 in groundwater were characteristic of a thermally postmature Marcellus-like source in some cases. Overall, our data suggest that some homeowners living <1 km from gas wells have drinking water contaminated with stray gases.
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Louis Anthony (Tony) Cox
Risk Analysis, forthcoming
Abstract:
Recent linear regression analyses have concluded that decreasing levels of fine particulate matter (PM2.5) air pollution have increased life expectancy in the United States. These findings have left unresolved questions about the causal relation between reductions in PM2.5 levels and changes in cause-specific (especially, cardiovascular disease, CVD) mortality risks. Their robustness (e.g., sensitivity to deletion of a single data point) has also been questioned. We investigate these issues in the National Mortality and Morbidity Air Pollution Study database. Comparing changes in PM2.5 levels and cause-specific mortality rates for elderly people in 24 cities between two periods separated by a decade (1987-1989 and 1999-2000) shows that reductions in PM2.5 were significantly associated with increases in respiratory mortality rates and with decreases in CVD mortality rates. CVD and all-cause mortality risks fell equally for all months of the year over this period, but average PM2.5 levels increased significantly for winter months. This casts doubts on the causal interpretation that declines in PM2.5 over the decade caused reduced short-term mortality risks. Nonlinear regression suggests that reduced or negative marginal health benefits are associated with reductions of PM2.5 below 1999-2000 levels (about 15 μg/m3). Such nonlinear relations imply that risk communication statements that project a constant incremental reduction in mortality risks per unit reduction in PM2.5 do not adequately reflect the realistic possibility of nonlinear exposure-response relations and diminishing returns to further exposure reductions.
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Testing the effect of defaults on the thermostat settings of OECD employees
Zachary Brown et al.
Energy Economics, September 2013, Pages 128-134
Abstract:
We describe a randomized controlled experiment in which the default settings on office thermostats in an OECD office building were manipulated during the winter heating season, and employees' chosen thermostat setting observed over a 6-week period. Using difference-in-differences, panel, and censored regression models (to control for maximum allowable thermostat settings), we find that a 1 °C decrease in the default caused a reduction in the chosen setting by 0.38 °C, on average. Sixty-five percent of this effect could be attributed to office occupant behavior (p-value = 0.044). The difference-in-differences models show that small decreases in the default (1°) led to a greater reduction in chosen settings than large decreases (2°). We also find that office occupants who were more apt to adjust their thermostats prior to the intervention were less susceptible to the default. We conclude that this kind of intervention can increase building-level energy efficiency, and discuss potential explanations and broader policy implications of our findings.
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Reforming Fisheries: Lessons from a Self-Selected Cooperative
Robert Deacon, Dominic Parker & Christopher Costello
Journal of Law and Economics, February 2013, Pages 83-125
Abstract:
We analyze a policy experiment in an Alaskan commercial fishery that assigned a portion of an overall catch quota to a voluntary co-op, with the remainder exploited competitively by those choosing to fish independently. Unlike the individual quota system advocated by many economists, the policy encouraged coordinated fishing and did not require a detailed assignment of rights. We model the decision to join and behavior under cooperative and independent fishing. The data confirm our key predictions: the co-op attracted the least skilled fishermen, consolidated and coordinated effort among its most efficient members, and provided shared infrastructure. We estimate that resulting gains in rent were at least 33 percent. Some independents were disadvantaged by the co-op's formation, however, which prompted them to oppose it in court. We analyze the source of their disadvantage and provide guidance for designing fishery reform that leads to Pareto improvements, enabling reform without losers.
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Carmen Carrión-Flores, Robert Innes & Abdoul Sam
Journal of Environmental Economics and Management, forthcoming
Abstract:
We study whether a government-sponsored voluntary pollution reduction program (VPR) promotes or deters the development of new environmental technologies that yield future emission reduction benefits. Using a panel of 127 U.S. manufacturing industries defined by 3-digit SIC classifications over the 1989-2004 period, we estimate impacts of industry-level participation in the 33/50 program, a VPR initiated by government regulators in 1991, on industry-level rates of environmental patenting. We find that higher rates of 33/50 program participation are associated with significant reductions in the number of successful environmental patent applications five to nine years after the program ended.
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Yield Trends Are Insufficient to Double Global Crop Production by 2050
Deepak Ray et al.
PLoS ONE, June 2013
Abstract:
Several studies have shown that global crop production needs to double by 2050 to meet the projected demands from rising population, diet shifts, and increasing biofuels consumption. Boosting crop yields to meet these rising demands, rather than clearing more land for agriculture has been highlighted as a preferred solution to meet this goal. However, we first need to understand how crop yields are changing globally, and whether we are on track to double production by 2050. Using ~2.5 million agricultural statistics, collected for ~13,500 political units across the world, we track four key global crops - maize, rice, wheat, and soybean - that currently produce nearly two-thirds of global agricultural calories. We find that yields in these top four crops are increasing at 1.6%, 1.0%, 0.9%, and 1.3% per year, non-compounding rates, respectively, which is less than the 2.4% per year rate required to double global production by 2050. At these rates global production in these crops would increase by ~67%, ~42%, ~38%, and ~55%, respectively, which is far below what is needed to meet projected demands in 2050. We present detailed maps to identify where rates must be increased to boost crop production and meet rising demands.
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Global human appropriation of net primary production doubled in the 20th century
Fridolin Krausmann et al.
Proceedings of the National Academy of Sciences, 18 June 2013, Pages 10324-10329
Abstract:
Global increases in population, consumption, and gross domestic product raise concerns about the sustainability of the current and future use of natural resources. The human appropriation of net primary production (HANPP) provides a useful measure of human intervention into the biosphere. The productive capacity of land is appropriated by harvesting or burning biomass and by converting natural ecosystems to managed lands with lower productivity. This work analyzes trends in HANPP from 1910 to 2005 and finds that although human population has grown fourfold and economic output 17-fold, global HANPP has only doubled. Despite this increase in efficiency, HANPP has still risen from 6.9 Gt of carbon per y in 1910 to 14.8 GtC/y in 2005, i.e., from 13% to 25% of the net primary production of potential vegetation. Biomass harvested per capita and year has slightly declined despite growth in consumption because of a decline in reliance on bioenergy and higher conversion efficiencies of primary biomass to products. The rise in efficiency is overwhelmingly due to increased crop yields, albeit frequently associated with substantial ecological costs, such as fossil energy inputs, soil degradation, and biodiversity loss. If humans can maintain the past trend lines in efficiency gains, we estimate that HANPP might only grow to 27-29% by 2050, but providing large amounts of bioenergy could increase global HANPP to 44%. This result calls for caution in refocusing the energy economy on land-based resources and for strategies that foster the continuation of increases in land-use efficiency without excessively increasing ecological costs of intensification.