Charles A Taylor
Research in environmental and health economics with a focus on climate, agriculture, land use, and ecosystem services. I like using satellite data and remote sensing products to help answer policy questions.
I will start as a S.V. Ciriacy-Wantrup postdoc at UC Berkeley ARE in August 2022, and afterwards I’ll be joining Harvard Kennedy School as an Assistant Professor. In May 2022, I completed my PhD in Sustainable Development at Columbia University.
I do applied micro research on environmental topics. I enjoy teaching and have taught environmental economics at Columbia, City College of New York, and Fordham University. Before academia, I worked at McKinsey & Company, the Bill & Melinda Gates Foundation as an agricultural consultant, and The Earth Partners LP, a land and environmental investment company, and I advise a niche agri-commodity exporting company. I co-founded Drylands Natural Resource Centre, a farmer-owned cooperative and research center. I have a BA in Economics and in Political & Social Thought from the University of Virginia.
“Cicadian Rhythm: Insecticides, Infant Health and Long-term Outcomes.” Job Market Paper
Pesticides are linked to negative health outcomes, but a causal relationship is difficult to establish due to nonrandom pesticide exposure. I use a peculiar ecological phenomenon, the mass emergence of cicadas in 13 and 17-year cycles across the eastern half of the US, to estimate the short and long-term impacts of pesticides. With a triple-difference setup that leverages the fact that cicadas only damage tree crops and not agricultural row crops, I show that insecticide use increases with cicada emergence in places with high apple production. Exposed cohorts experience higher infant mortality and adverse health impacts, followed by lower test scores and higher dropout rates. I exploit geo-spatial sources of variation and find evidence for pesticide exposure through a water channel. Moderate levels of environmental pollution, not just extreme exposure, can affect human health and development. The study design, which encompasses the entire chemical era of US agriculture since 1950, provides insights into the regulation of pesticides in the US and globally.
“Wetlands, Flooding, and the Clean Water Act.” American Economic Review (with Hannah Druckenmiller), 2022
In 2020 the EPA narrowed the definition of ‘Waters of the United States’, significantly limiting wetland protection under the Clean Water Act. Current policy debates center on the uncertainty around wetland benefits. We estimate the value of wetlands for flood mitigation across the US using detailed flood claims and land use data. We find the average hectare of wetland lost between 2001 and 2016 cost society $1,840 annually, and over $8,000 in developed areas. We document significant spatial heterogeneity in wetland benefits, with implications for flood insurance policy and the 50% of ‘isolated’ wetlands at risk of losing federal protection. (ungated)
“Livestock Plants and COVID-19 Transmission.” Proceedings of the National Academy of Sciences (with Chris Boulos and Douglas Almond), 2020
Policy responses to the COVID-19 outbreak must strike a balance between maintaining essential supply chains and limiting the spread of the virus. Our results indicate a strong positive relationship between livestock-processing plants and local community transmission of COVID-19, suggesting that these plants may act as transmission vectors into the surrounding population and accelerate the spread of the virus beyond what would be predicted solely by population risk characteristics. We estimate the total excess COVID-19 cases and deaths associated with proximity to livestock plants to be 236,000 to 310,000 (6 to 8% of all US cases) and 4,300 to 5,200 (3 to 4% of all US deaths), respectively, as of July 2020, with the vast majority likely related to community spread outside these plants. The association is found primarily among large processing facilities and large meatpacking companies. In addition, we find evidence that plant closures attenuated county-wide cases and that plants that received USDA permission to increase their production-line speeds saw more county-wide cases.
“Market Expectations of a Warming Climate.” Journal of Financial Economics (with Wolfram Schlenker), 2021
We compare prices of financial derivatives whose payouts are based on future weather outcomes to CMIP5 climate model predictions as well as observed weather station data across eight cities in the US from 2001 through 2020. Derivative prices respond both to short-term weather forecasts for the next two weeks and longer-term warming trends. We show that the long-term trends in derivative prices are comparable to station-level data and climate model output. The one exception is February in the northeastern US, where financial markets price in a polar vortex-induced cooling effect, a recent scientific finding that was not present in the older CMIP5 climate output. When looking at the spatial and temporal heterogeneity in trends, futures prices are more aligned with climate model output than observed weather station trends, suggesting that market participants closely align their expectations with scientific projections rather than recent observations.
“Fertilizer and Algal Blooms: A Satellite Approach to Assessing Water Quality.” NBER Risks in Agricultural Supply Chains, Book Chapter (with Geoffrey Heal), forthcoming
Fertilizer is critical to agricultural supply chains, but its use results in downstream externalities in the form of aquatic hypoxic zones and algal blooms. Quantifying farm pollution is challenging due to its non-point nature and the lack of a temporally consistent, administrative-level dataset on water quality. This study offers a novel satellite-derived measure of algal bloom intensity that spans 30-plus years and encompasses lakes, riparian, and coastal aquatic resources across US counties. We show that fertilizer use is closely linked to our measure of water quality. Such farm pollution drives water quality impairment both locally and downstream from the fertilizer use, with impacts occurring at an annual and longer-term timescale.
“Algal Blooms and the Social Cost of Fertilizer.” Working Paper (with Geoffrey Heal)
Fertilizer is a major source of water pollution that causes widespread algal blooms and threatens aquatic ecosystems. Driven by agriculture, the benefits of fertilizer accrue to farmers but the costs are borne to downstream water users. The negative externality has yet to be quantified at a large scale in the US, partly because most farm pollution is unregulated under the Clean Water Act, and partly due to the lack of temporally-consistent, administrative-level water quality data. This study utilizes a long-term satellite-derived measure of algal bloom intensity that encompasses lakes, rivers, and coastal areas. We find a significant negative economic impact of algal blooms in locations downstream from agricultural areas, as well as in water-reliant regions (e.g., coastal areas) and economic sectors (e.g., fishing, tourism, recreation). The reduction in income extends for up to four years following high intensity algal blooms. From these results, we estimate the external cost of nitrogen fertilizer to be $580 per ton, or 66% of its 2020 market value.
“Environmental Drivers of Agricultural Productivity Growth: CO2 Fertilization of US Field Crops.” NBER Working Paper w29320 (with Wolfram Schlenker), 2021
We assess the CO2 fertilization effect on US agriculture using spatially-varying CO2 data from NASA’s Orbiting Carbon Observatory-2 (OCO-2) satellite covering the majority of US cropland under actual growing conditions. This study complements the many CO2 enrichment experiments that have found important interactions between CO2 and local environmental conditions in controlled settings. We use three empirical strategies: (i) a panel of CO2 anomalies and county yields, (ii) a panel of spatial first-differences between neighboring counties, and (iii) a cross-sectional spatial first-difference. We find consistently high fertilization effects: a 1 ppm increase in CO2 equates to a 0.5%, 0.6%, and 0.8% yield increase for corn, soybeans, and wheat, respectively. Viewed retrospectively, 10%, 30%, and 40% of each crop’s yield improvements since 1940 are attributable to rising CO2.
As the largest user of global water, irrigated agriculture accounts for 20% of global cropland and 40% of food production. Irrigation is also a potential adaptive response to drought and extreme temperatures. This paper examines the extent to which the current global irrigation footprint reflects climate change over the last 50 years. Utilizing exogenous variation in geological structure, I find evidence that farmers adapt by increasing irrigation in places that became dryer and hotter. The results hold globally and in the US. Observed recent warming is responsible for 9% of global irrigation growth. GRACE satellite data shows that climate-driven irrigation contributes to aquifer stress, as well as increased soil salinity, thus representing large negative externalities of adaptation to climate change and a potential threat to future food security.
“Tipping point dynamics in global land use.” Environmental Research Letters (with James Rising), 2021
Agricultural land use has recently peaked, both globally and across country income groups, after centuries of expansion and intensification. Such shifts in the evolution of global land use have implications for food security, biodiversity loss, and carbon emissions. While economic growth and land use are closely linked, it is difficult to determine the extent to which the relationship is causal, deterministic, and unidirectional. Here we utilize gridded datasets to study long-term global land use change from 1780-2010. We find evidence for an economic tipping point, where land use intensifies with economic development at low income levels, then reverses after incomes reach a critical threshold. Cropland peaks around $5,000 GDP per capita then declines. We utilize a Markov model to show that this reversal emerges from a variety of divergent land use pathways, in particular the expansion of protected areas and a reduction in land use lock-in. Our results suggest that economic development remains a powerful driver of land use change with implications for the future of natural ecosystems in the context of continued population and income growth.
“Violent conflict exacerbated drought-related food insecurity between 2009 and 2019 in sub-Saharan Africa.” Nature Food (with W Anderson, C Taylor, S McDermid, E Ilboudo-Nébié, R Seager, W Schlenker, F Cottier, A de Sherbinin, D Mendeloff, K Markey), 2021
Conflict, drought and locusts are leading concerns for African food security but the relative importance and spatiotemporal scale of crises resulting from each hazard is poorly characterized. Here we use continuous, subnational data to demonstrate that the rise of food insecurity across sub-Saharan Africa that began in 2014 is attributable to an increase in violent conflict, particularly in South Sudan and Nigeria. Although drought remains a leading trigger of food crises, the prevalence of drought-related crises did not increase from 2009 to 2018. When exposed to drought, pastoralists experienced more widespread, severe and long-lasting food crises than people living in agricultural zones. Food insecurity remained elevated in pastoral regions for 2 years following a drought, while agricultural regions returned to pre-drought food-security levels in ~12 months. The few confirmed famines during the 2009–2018 period coincided with both conflict and drought, while locusts had little effect on food security during this period.
“The 1968 Influenza Pandemic and COVID-19 Outcomes.” Preprint on medRxiv (with Chris Boulos and Matthew Memoli)
Past pandemic experience at an individual or population level may affect health outcomes in future pandemics. In this study, we focus on how the influenza pandemic of 1968 (H3N2), which killed up to 100,000 people in the US, may have produced differential COVID-19 (SARS-CoV-2) outcomes. Our analysis finds that areas with high influenza-related mortality in 1968 experienced 1-2% lower COVID-19 death rates. We employ an identification strategy that isolates variation in COVID-19 rates across age cohorts born before and after 1968. Locales in the US with high 1968 influenza mortality have lower COVID-19 death rates among older cohorts relative to younger ones. The relationship holds using county-level and patient-level data, as well as data from hospitals and nursing homes. Results do not appear to be driven by systemic or policy-related factors that would affect a population, but instead suggest an individual-level response to prior influenza pandemic exposure. The findings merit further investigation into potential biological, immunological, or other mechanisms that account for these differences.
“Cicadas, insecticides and children,” The Economist (June 2021)
“The Trump administration approved faster line speeds at chicken plants. Those facilities are more likely to have Covid-19 cases,” by Kimberly Kindy, Ted Mellnik and Arelis R. Hernandez, The Washington Post (January 2021)
“Study Ties 6% to 8% of U.S. Covid Cases to Meatpacking Plants,” by Mike Dorning, Bloomberg (November 2020)
“OSHA issues a new Covid safety rule, but only for the health care industry,” by Noam Scheiber, The New York Times (June 2021)
“The market is betting on climate change,” The Economist (March 2019)
Charles A Taylor
420 W 118th St
New York, NY 10027
cat2180 (at) columbia (dot) edu
cha (dot) taylor (at) gmail (dot) com