Surroundings
Financial Value of Nature: Coastal Housing Markets, Mangroves, and Climate Resilience
Teng Liu et al.
NBER Working Paper, October 2025
Abstract:
Measuring the financial value of nature is difficult, often resulting in insufficient funding directed to nature conservation and restoration. As coastal risks increase from development and climate change, a tangible benefit of nature is the protection it offers against storm damages. Many studies from the risk industry and others assess the direct effects of wetlands for reducing damage during storms. However, the value of wetlands for coastal protection could extend to many other benefits, including home prices in areas where storms are common. We use property-level housing transaction data from Zillow and show that proximity to mangroves in Florida moderates home price decline and dispersion following major hurricanes. The effects are substantial in magnitude, reducing the probability of losing a quarter or more of housing value by 2-7 percentage points, which corresponds to 20-40-thousand-dollar value for a million-dollar property, conditional on a hurricane.
Balanced Messaging about Solar Geoengineering does not Reduce Average Support for Emissions Reductions
Damian Antoan et al.
Journal of Experimental Political Science, forthcoming
Abstract:
Solar geoengineering offers a speculative means to cool the planet by reflecting solar radiation into space. While some research suggests that awareness of solar geoengineering could reduce public support for decarbonization through a moral hazard mechanism, other studies indicate that it could serve as a "clarion call" that motivates further action. Using a pre-registered factorial design, we assess how sharing balanced information on solar geoengineering affects attitudes toward decarbonization policies and climate attitudes among 2,509 US residents. We do not find that solar geoengineering information affects support for decarbonization on average, though it may increase support among initially less supportive subgroups; moreover, this information tends to increase the perception that climate change is a daunting problem that cannot be resolved without decarbonization. Our results suggest that concerns about moral hazard should not discourage research on solar geoengineering - as long as the public encounters realistic messages about solar geoengineering's role.
Typhoid Contamination and Self-Regulation of London's Shellfish Industry
Vincent Geloso & Nicky Tynan
George Mason University Working Paper, June 2025
Abstract:
By the early twentieth century, London had lower typhoid mortality than most British, European, and American cities. While water infrastructure improvements played a role, a plateau in death rates after the 1880s suggests other factors. This paper argues that contaminated shellfish -- harvested near urban wastewater -- became a key vector of transmission. As consumer awareness grew, the shellfish market faced the threat of collapse. Yet, the industry survived due to self-regulation by the Worshipful Company of Fishmongers, which used the Billingsgate market to segment products by quality and signal safety. We interpret this as a case where private coordination offset asymmetric information, avoided a lemons market, and complemented public health efforts. The findings contribute to literatures on core theory, entrepreneurial discovery, and the role of private solutions in public health.
Understanding and Addressing Temperature Impacts on Mortality
Marshall Burke et al.
NBER Working Paper, October 2025
Abstract:
A large literature documents how ambient temperature affects human mortality. Using decades of detailed data from 30 countries, we revisit and synthesize key findings from this literature. We confirm that ambient temperature is among the largest external threats to human health, and is responsible for a remarkable 5-12% of total deaths across countries in our sample, or hundreds of thousands of deaths per year in both the U.S. and EU. In all contexts we consider, cold kills more than heat, though the temperature of minimum risk rises with age, making younger individuals more vulnerable to heat and older individuals more vulnerable to cold. We find evidence for adaptation to the local climate, with hotter places experiencing somewhat lower risk at higher temperatures, but still more overall mortality from heat due to more frequent exposure. Within countries, higher income is not associated with uniformly lower vulnerability to ambient temperature, and the overall burden of mortality from ambient temperature is not falling over time. Finally, we systematically summarize the limited set of studies that rigorously evaluate interventions that can reduce the impact of heat and cold on health. We find that many proposed and implemented policy interventions lack empirical support and do not target temperature exposures that generate the highest health burden, and that some of the most beneficial interventions for reducing the health impacts of cold or heat have little explicit to do with climate.
Oil Shocks & Suicide
Chandler Hubbard, Alexander James & Makenzi Scott
University of Wyoming Working Paper, September 2025
Abstract:
We estimate the effect of positive and negative oil shocks on suicide. Using restricted-use, U.S. state-level mortality data, we find that economic losses increase suicide risk and that economic gains have little effect. From 2015-2020, at least 6,000 people in the United States died by suicide as a result of declining oil prices. Exploring sources of heterogeneity, effects are largely driven by men, people without college degrees, and racial minorities. Results are robust to various modeling decisions and assumptions and are not easily explained by compositional changes. Implications are discussed, particularly as they relate to the clean energy transition.
Forgoing Nuclear: Nuclear Power Plant Closures and Carbon Emissions in the United States
Luke Petach
Southern Economic Journal, forthcoming
Abstract:
This paper examines the effect of nuclear power plant decommissioning on electricity generation and carbon emissions in the United States. Using data on nuclear reactor closures in the United States between 1993 and 2022 and data on state-level carbon emissions and electricity generation from the Energy Information Administration (EIA), this paper adopts a difference-in-differences (DiD) approach to estimate the effect of nuclear decommissioning. Two-way fixed-effects (TWFE) DiD estimates suggest a nuclear plant closure increases annual state-level per capita carbon emissions between 6% and 8%. The increase in state-level carbon emissions is driven by a substitution toward fossil fuel electricity -- particularly coal-fired electricity -- following a plant closure. To address concerns about bias in TWFE estimates stemming from heterogeneous treatment effects and/or variation in treatment timing, I implement two alternative estimators robust to treatment effect heterogeneity. Estimates from both the Callaway and Sant'Anna (2021) and Borusyak et al. (2024) estimators support the TWFE findings: nuclear power plant closures increase per capita carbon emissions at the state level.
The Traffic Noise Externality: Costs, Incidence and Policy Implications
Enrico Moretti & Harrison Wheeler
NBER Working Paper, September 2025
Abstract:
More than 42 million Americans are exposed to medium or high levels of traffic noise. Despite its potentially large toll and unequal distribution, the economic costs, incidence, and policy implications of traffic noise have received limited attention in economics. We quantify the aggregate economic burden of this externality and its distribution across demographic groups by estimating homebuyers' willingness to pay for quieter environments. Using quasi-experimental variation from the construction of noise barriers, we find that reduced traffic noise exposure leads to significant increases in house prices, implying that buyers are willing to pay a substantial premium for each decibel of noise reduction. In the five years before construction, we detect no differential pre-trends in prices between treated and control properties. Following construction, we observe an immediate and largely permanent 6.8% increase in prices within 100 meters, with smaller gains at greater distances. Information on each barrier's noise attenuation allows us to recover the willingness to pay per decibel of traffic noise. We calculate the aggregate economic cost of traffic noise at $110 billion nationwide. The economic burden is disproportionately borne by lower income and minority households, suggesting that the externality is regressive. The cost varies widely across cities, reflecting differences in noise levels, property values and population density. Based on our estimates, the socially efficient Pigouvian tax amounts to $974 per vehicle. A broad shift to electric vehicles -- which are quieter than traditional vehicles -- could yield noise reduction benefits of $77.3 billion, concentrated among low-income families in dense urban areas.
Congestion Pricing in New York City: Effects on Ride-Hailing, Transit, and Welfare
Yueshan Zhang, Yanling Sang & Manxi Wu
University of California Working Paper, September 2025
Abstract:
On January 5, 2025, New York City introduced a $1.50 congestion surcharge on for-hire vehicles operating within the Central Business District. This study examines the effects of the policy on Uber, Lyft, and subway ridership using two-way fixed effects analysis. Leveraging Lyft's temporary $1.50 rider credit in January 2025, we analyze the impact of tolling on Uber and Lyft separately. Results show that Uber trips declined by up to 6%, while Lyft trips increased by 2-5% during the subsidy period and remained slightly elevated afterward. Overall ride-hailing volume fell by 0.5-1.5%, while subway ridership rose by approximately 1%, which suggests partial modal substitution. The toll's impact was concentrated among short trips and low-fare rides, which declined by over 9% and 35%, respectively, while longer and higher-fare trips were largely unaffected. Interestingly, we find that base fares and platform revenue per trip increased, especially for Uber, while driver pay gains were limited. Our findings highlight how tolls and platforms' response strategies jointly shape the ridership pattern and welfare distributions.
Climate Change, Conflict, and the Risk of Economic Collapse in Africa
Joel Ferguson et al.
NBER Working Paper, October 2025
Abstract:
Is human-caused climate change likely to trigger enduring economic decline in modern societies? We study whether changes in violent conflict and economic growth caused by warming could interact to degrade economic opportunities and trap African countries in poverty. We provide evidence of an emerging high-conflict and low-growth "poverty trap" equilibrium in Africa and describe theoretically how such an equilibrium could result from warming. We then combine historical data on temperature, growth, and conflict with projections from a large ensemble of global climate models to evaluate the risk that warming and subsequent conflict could push African economies into a regime of sustained negative economic growth. We find that the risk of such "economic collapse" is material in a moderate-to-high emissions scenario. We estimate that in Africa, a current "high" emissions trajectory (RCP 7.0) may increase the incidence of conflict 5.1 percentage points (95% CI 0.2-13.0) and increase the share of countries with net negative GDP growth this century by 12.2 percentage points (95% CI 2.0-27.5). We calculate that roughly 82% of this additional conflict risk and 14% of projected GDP losses are due to the interacting effects between these two outcomes, underscoring the importance of accounting for their indirect effects and feedbacks. Our findings suggest an unprecedented scale of emissions mitigation, economic policy innovation or institutional investment that would be required to contain the risk of catastrophic human impacts from climate change in many African countries.
Unpacking the extinction crisis: Rates, patterns and causes of recent extinctions in plants and animals
Kristen Saban & John Wiens
Proceedings of the Royal Society: Biological Sciences, October 2025
Abstract:
Biodiversity loss is one of the greatest challenges facing Earth today. The most direct information on species losses comes from recent extinctions. However, our understanding of these recent, human-related extinctions is incomplete across life, especially their causes and their rates and patterns among clades, across habitats and over time. Furthermore, prominent studies have extrapolated from these extinctions to suggest a current mass extinction event. Such extrapolations assume that recent extinctions predict current extinction risk and are homogeneous among groups, over time and among environments. Here, we analyse rates and patterns of recent extinctions (last 500 years). Surprisingly, past extinctions did not strongly predict current risk among groups. Extinctions varied strongly among groups, and were most frequent among molluscs and some tetrapods, and relatively rare in plants and arthropods. Extinction rates have increased over the last five centuries, but generally declined in the last 100 years. Recent extinctions were predominantly on islands, whereas the majority of non-island extinctions were in freshwater. Island extinctions were most frequently related to invasive species, but habitat loss was the most important cause (and current threat) in continental regions. Overall, we identify the major patterns in recent extinctions but caution against extrapolating them into the future.
Strategic Avoidance and the Welfare Impacts of U.S. Solar Panel Tariffs
Todd Gerarden et al.
NBER Working Paper, October 2025
Abstract:
This study examines the effects of tariffs imposed by the U.S. on imported solar panels. We first provide clear evidence that tariff-exposed firms shifted production to locations that did not face tariffs, and that domestic prices increased relative to other markets. We then develop a structural model to analyze welfare effects. We find that the tariffs generated modest gains for domestic manufacturers and for government revenues, but larger losses in domestic consumer surplus and environmental benefits, thereby reducing domestic welfare. Furthermore, the tariffs reduced domestic solar industry employment and wages. By contrast, subsidizing solar panel manufacturing could increase domestic production, employment, and welfare.