Conference Agenda

Air pollution from natural sources is often subject to less regulatory oversight, but can still be

caused by human activities. Understanding the role for policy requires quantifying the source's

pollution contribution, for which there is currently no standard methodological approach. This

paper uses the context of the shrinking Great Salt Lake in Utah to model air quality impacts of the highly erodible and growing area of exposed lakebed. Using four common identification

strategies in the air pollution literature, and three alternative pollution measurement technologies, we find consistent evidence of meaningful pollution increases attributable to the shrinking lake in non-winter months. Estimates are relatively invariant to measurement technology but vary across identification strategies. Marginal annual costs range from $81 to $175 million per 100 km² of exposed lakebed. Scaling to the area of total exposed lakebed, annual desiccation-related health cost estimates range from $1.1 billion to $2.3 billion. Given the direct relationship between human water use in the basin and exposed lakebed, these results provide evidence for the cost-effectiveness of policies aimed at reducing consumptive water use.

Extreme heatwaves can undermine the efficiency of fossil-fuel power generation, amplifying air pollution and health risks. Using plant-level operational data and high-resolution weather data from China, we find that during the 2022 extreme heatwave in Guangdong Province, exposed plants experienced approximately 21.4% higher PM2.5 emission intensity relative to unexposed plants, an increase attributable to heatwave-induced efficiency losses. Coal-fired plants exhibited an additional 12.3% increase relative to gas-fired plants. Similar patterns are observed for other combustion-related pollutants. We estimate that heatwave-induced pollution from power-sector efficiency losses imposes an annual social cost of USD 4.21 billion in China, which could be reduced by USD 1.42 billion under a complete coal-to-gas substitution scenario. Looking ahead, under the high-emissions SSP5-8.5 scenario, which is associated with approximately 4.4°C of warming by 2100, annual costs in China could rise to USD 20.41 billion. The impacts are highly uneven across provinces, with coal-dependent and industrial coastal regions disproportionately affected. Our findings highlight how extreme heatwaves can amplify air pollution and health damages through an overlooked energy-sector efficiency channel, underscoring the broader societal costs of continued fossil-fuel dependence in a warming world.

Using quarterly, county-level employment and wage data spanning 1996–2023, this study investigates the labor market consequences of floods- historically among the most lethal and expensive natural disasters in the United States. We distinguish between flash floods and floods with gradual, slower onset patterns (non-flash floods), and explore how the impacts vary across temporal windows (sub-annual versus annual), location (inland versus coastal counties), sectors, and existing labor market conditions. Our results show that an additional day of flash floods in a quarter reduces county-level employment and wages by 0.13% and 0.15% respectively. We find that total wages decreased by $6.2 billion per year (in 2023 USD) between 1996 and 2023 as a result of flash and non-flash floods. Heterogeneous effects reveal that economically vulnerable counties experience larger negative impacts from both flood types and that both coastal and inland counties face negative economic disruptions. Our findings underscore that sub-annual impacts are crucial for understanding flood impacts and designing policies that build resilience to shocks.

Land use alternations and climate change are shifting natural fire regimes, leading to prolonged and intensified fire seasons accompanied by widespread air pollution, with potentially important consequences for local wildlife. Combining data from the North American Breeding Bird Survey with high-resolution satellite imagery, we estimate the impact of wildfire-specific smoke pollution (PM2.5) on avian biodiversity in the contiguous United States (US) from 2008 to 2022. The panel fixed effects instrumental variable estimation results indicate a short-term adverse effect of PM2.5 on taxonomic and phylogenetic diversity metrics. More specifically, a standard deviation (sd) increase in wildfire-specific PM2.5 pollution reduces species richness, abundance, and phylogenetic diversity by about 0.1 sd, largely driven by observations in the Western US. For the most polluted transects the effect is up to 2-3 standard deviations. The adverse effects on biodiversity metrics vary markedly across ecosystems. While the decrease in phylogenetic diversity is most pronounced in the Western US, for the taxonomic metrics it is the Eastern Temperate Forests, the Northern Forests, and the North American Deserts, which are driving the adverse effect of wildfire smoke. These findings underscore the need for targeted fire management and conservation strategies to mitigate biodiversity loss, especially in the face of increasing wildfire intensity and smoke exposure projected for many regions worldwide.