Bio


Marshall Burke is an associate professor in Global Environmental Policy unit in the Doerr School of Sustainability, deputy director at the Center on Food Security and the Environment, and Senior Fellow at the Freeman Spogli Institute for International Studies (FSI), Woods Institute, and SIEPR at Stanford University. He is also a faculty research fellow at the National Bureau of Economic Research, and a co-founder of AtlasAI, a remote sensing start-up. His research focuses on social and economic impacts of environmental change and on measuring and understanding economic development in emerging markets. His work has appeared in both economic and scientific journals, including recent publications in Nature, Science, The Quarterly Journal of Economics, and The Lancet. He holds a PhD in agricultural and resource economics from the University of California, Berkeley and a BA in international relations from Stanford University.

Prospective students should see my personal webpage, linked at right.

Program Affiliations


  • Program in International Relations

2023-24 Courses


Stanford Advisees


All Publications


  • Sociodemographic and geographic variation in mortality attributable to air pollution in the United States. medRxiv : the preprint server for health sciences Geldsetzer, P., Fridljand, D., Kiang, M. V., Bendavid, E., Heft-Neal, S., Burke, M., Thieme, A. H., Benmarhnia, T. 2024

    Abstract

    There are large differences in premature mortality in the USA by racial/ethnic, education, rurality, and social vulnerability index groups. Using existing concentration-response functions, particulate matter (PM2.5) air pollution, population estimates at the tract level, and county-level mortality data, we estimated the degree to which these mortality discrepancies can be attributed to differences in exposure and susceptibility to PM2.5. We show that differences in mortality attributable to PM2.5 were consistently more pronounced between racial/ethnic groups than by education, rurality, or social vulnerability index, with the Black American population having by far the highest proportion of deaths attributable to PM2.5 in all years from 1990 to 2016. Over half of the difference in age-adjusted all-cause mortality between the Black American and non-Hispanic White population was attributable to PM2.5 in the years 2000 to 2011.

    View details for DOI 10.1101/2024.04.17.24305943

    View details for PubMedID 38699349

    View details for PubMedCentralID PMC11065005

  • Climate warming is expanding dengue burden in the Americas and Asia. medRxiv : the preprint server for health sciences Childs, M. L., Lyberger, K., Harris, M., Burke, M., Mordecai, E. A. 2024

    Abstract

    Climate change poses significant threats to public health, with dengue representing a growing concern due to its high existing burden and sensitivity to climatic conditions. Yet, the quantitative impacts of temperature warming on dengue, both in the past and in the future, remain poorly understood. In this study, we quantify how dengue responds to climatic fluctuations, and use this inferred temperature response to estimate the impacts of historical warming and forecast trends under future climate change scenarios. To estimate the causal impact of temperature on the spread of dengue in the Americas and Asia, we assembled a dataset encompassing nearly 1.5 million dengue incidence records from 21 countries. Our analysis revealed a nonlinear relationship between temperature and dengue incidence with the largest marginal effects at lower temperatures (around 15°C), peak incidence at 27.8°C (95% CI: 27.3 - 28.2°C), and subsequent declines at higher temperatures. Our findings indicate that historical climate change has already increased dengue incidence 18% (12 - 25%) in the study region, and projections suggest a potential increase of 40% (17 - 76) to 57% (33 - 107%) by mid-century depending on the climate scenario, with some areas seeing up to 200% increases. Notably, our models suggest that lower emissions scenarios would substantially reduce the warming-driven increase in dengue burden. Together, these insights contribute to the broader understanding of how long-term climate patterns influence dengue, providing a valuable foundation for public health planning and the development of strategies to mitigate future risks due to climate change.

    View details for DOI 10.1101/2024.01.08.24301015

    View details for PubMedID 38260629

    View details for PubMedCentralID PMC10802639

  • Exposure to Nitrogen Dioxide and Fine Particulate Matter When Cooking with Electricity Compared to Gas, a Randomized Crossover Study in Quito, Ecuador. Environmental health perspectives Gould, C. F., Davila, L., Bejarano, M. L., Burke, M., Jack, D. W., Schlesinger, S. B., Mora, J. R., Valarezo, A. 2024; 132 (1): 17702

    View details for DOI 10.1289/EHP13134

    View details for PubMedID 38261301

  • Quantifying fire-specific smoke exposure and health impacts. Proceedings of the National Academy of Sciences of the United States of America Wen, J., Heft-Neal, S., Baylis, P., Boomhower, J., Burke, M. 2023; 120 (51): e2309325120

    Abstract

    Rapidly changing wildfire regimes across the Western United States have driven more frequent and severe wildfires, resulting in wide-ranging societal threats from wildfires and wildfire-generated smoke. However, common measures of fire severity focus on what is burned, disregarding the societal impacts of smoke generated from each fire. We combine satellite-derived fire scars, air parcel trajectories from individual fires, and predicted smoke PM2.5 to link source fires to resulting smoke PM2.5 and health impacts experienced by populations in the contiguous United States from April 2006 to 2020. We quantify fire-specific accumulated smoke exposure based on the cumulative population exposed to smoke PM2.5 over the duration of a fire and estimate excess asthma-related emergency department (ED) visits as a result of this exposure. We find that excess asthma visits attributable to each fire are only moderately correlated with common measures of wildfire severity, including burned area, structures destroyed, and suppression cost. Additionally, while recent California fires contributed nearly half of the country's smoke-related excess asthma ED visits during our study period, the most severe individual fire was the 2007 Bugaboo fire in the Southeast. We estimate that a majority of smoke PM2.5 comes from sources outside the local jurisdictions where the smoke is experienced, with 87% coming from fires in other counties and 60% from fires in other states. Our approach could enable broad-scale assessment of whether specific fire characteristics affect smoke toxicity or impact, inform cost-effectiveness assessments for allocation of suppression resources, and help clarify the growing transboundary nature of local air quality.

    View details for DOI 10.1073/pnas.2309325120

    View details for PubMedID 38085772

  • Reply to Giglio and Roy: Aggregate infant mortality estimates robust to choice of burned area product. Proceedings of the National Academy of Sciences of the United States of America Pullabhotla, H., Zahid, M., Heft-Neal, S., Rathi, V., Burke, M. 2023; 120 (51): e2318188120

    View details for DOI 10.1073/pnas.2318188120

    View details for PubMedID 38060525

  • In praise of fossil fuel subsidies (for cooking). medRxiv : the preprint server for health sciences Gould, C. F., Bailis, R., Balakrishnan, K., Burke, M., Espinoza, S., Mehta, S., Schlesinger, S. B., Suarez-Lopez, J. R., Pillarisetti, A. 2023

    Abstract

    We use three quantitative case studies to argue that ubiquitous and universal condemnation of fossil fuel subsidies is myopic and does not adequately consider subsidizing gas for cooking as a potential strategy to improve public health and reduce greenhouse gas emissions. Ecuador offers a view into the long-run impacts of gas subsidies, having made historical investments in subsidizing gas for cooking that led to widespread use that outpaces peer nations. We calculate that the subsidy likely averted 100,000 premature deaths with benefits that outweigh costs four to one. India successfully implemented the largest gas cooking access program in the world, but the level of subsidies provided by the government has varied. We estimate that mortality and climate benefits from maintaining varying levels of the gas subsidy between 2023-2030 will be roughly double costs. In Kenya, removing a value added tax on LPG will yield health and climate benefits that will dwarf the lost revenue by ~30x. Waiting for existing policies and momentum to move households toward near-exclusive clean fuel use forces marginalized populations to directly face the health, environmental, and socio-economic harms of traditional cooking. Rather than wait decades for development to provide clean cooking to these households, which will deepen health and energy inequities, we suggest that targeted LPG subsidies offer a solution available today and provide immediate health and climate benefits.

    View details for DOI 10.1101/2023.10.26.23297550

    View details for PubMedID 37961585

    View details for PubMedCentralID PMC10635205

  • Emergency department visits respond nonlinearly to wildfire smoke. Proceedings of the National Academy of Sciences of the United States of America Heft-Neal, S., Gould, C. F., Childs, M. L., Kiang, M. V., Nadeau, K. C., Duggan, M., Bendavid, E., Burke, M. 2023; 120 (39): e2302409120

    Abstract

    Air pollution negatively affects a range of health outcomes. Wildfire smoke is an increasingly important contributor to air pollution, yet wildfire smoke events are highly salient and could induce behavioral responses that alter health impacts. We combine geolocated data covering all emergency department (ED) visits to nonfederal hospitals in California from 2006 to 2017 with spatially resolved estimates of daily wildfire smoke PM[Formula: see text] concentrations and quantify how smoke events affect ED visits. Total ED visits respond nonlinearly to smoke concentrations. Relative to a day with no smoke, total visits increase by 1 to 1.5% in the week following low or moderate smoke days but decline by 6 to 9% following extreme smoke days. Reductions persist for at least a month. Declines at extreme levels are driven by diagnoses not thought to be acutely impacted by pollution, including accidental injuries and several nonurgent symptoms, and declines come disproportionately from less-insured populations. In contrast, health outcomes with the strongest physiological link to short-term air pollution increase dramatically in the week following an extreme smoke day: We estimate that ED visits for asthma, COPD, and cough all increase by 30 to 110%. Data from internet searches, vehicle traffic sensors, and park visits indicate behavioral changes on high smoke days consistent with declines in healthcare utilization. Because low and moderate smoke days vastly outweigh high smoke days, we estimate that smoke was responsible for an average of 3,010 (95% CI: 1,760-4,380) additional ED visits per year 2006 to 2017. Given the increasing intensity of wildfire smoke events, behavioral mediation is likely to play a growing role in determining total smoke impacts.

    View details for DOI 10.1073/pnas.2302409120

    View details for PubMedID 37722035

  • Health Effects of Wildfire Smoke Exposure. Annual review of medicine Gould, C. F., Heft-Neal, S., Prunicki, M., Aguilera, J., Burke, M., Nadeau, K. 2023

    Abstract

    We review current knowledge on the trends and drivers of global wildfire activity, advances in the measurement of wildfire smoke exposure, and evidence on the health effects of this exposure. We describe methodological issues in estimating the causal effects of wildfire smoke exposures on health and quantify their importance, emphasizing the role of nonlinear and lagged effects. We conduct a systematic review and meta-analysis of the health effects of wildfire smoke exposure, finding positive impacts on all-cause mortality and respiratory hospitalizations but less consistent evidence on cardiovascular morbidity. We conclude by highlighting priority areas for future research, including leveraging recently developed spatially and temporally resolved wildfire-specific ambient air pollution data to improve estimates of the health effects of wildfire smoke exposure. Expected final online publication date for the Annual Review of Medicine, Volume 75 is January 2024. Please see http://www.annualreviews.org/page/journal/pubdates for revised estimates.

    View details for DOI 10.1146/annurev-med-052422-020909

    View details for PubMedID 37738508

  • The contribution of wildfire to PM2.5 trends in the USA. Nature Burke, M., Childs, M. L., de la Cuesta, B., Qiu, M., Li, J., Gould, C. F., Heft-Neal, S., Wara, M. 2023

    Abstract

    Steady improvements in ambient air quality in the USA over the past several decades, in part a result of public policy1,2, have led to public health benefits1-4. However, recent trends in ambient concentrations of particulate matter with diameters less than 2.5 μm (PM2.5), a pollutant regulated under the Clean Air Act1, have stagnated or begun to reverse throughout much of the USA5. Here we use a combination of ground- and satellite-based air pollution data from 2000 to 2022 to quantify the contribution of wildfire smoke to these PM2.5 trends. We find that since at least 2016, wildfire smoke has influenced trends in average annual PM2.5 concentrations in nearly three-quarters of states in the contiguous USA, eroding about 25% of previous multi-decadal progress in reducing PM2.5 concentrations on average in those states, equivalent to 4 years of air quality progress, and more than 50% in many western states. Smoke influence on trends in the number of days with extreme PM2.5 concentrations is detectable by 2011, but the influence can be detected primarily in western and mid-western states. Wildfire-driven increases in ambient PM2.5 concentrations are unregulated under current air pollution law6 and, in the absence of further interventions, we show that the contribution of wildfire to regional and national air quality trends is likely to grow as the climate continues to warm.

    View details for DOI 10.1038/s41586-023-06522-6

    View details for PubMedID 37730996

    View details for PubMedCentralID 3521092

  • Wildfires are worsening air quality in the United States NATURE Burke, M., Childs, M. 2023

    View details for DOI 10.1038/d41586-023-02794-0

    View details for Web of Science ID 001079222200011

    View details for PubMedID 37730773

    View details for PubMedCentralID 5081637

  • Climate and health benefits of a transition from gas to electric cooking. Proceedings of the National Academy of Sciences of the United States of America Gould, C. F., Bejarano, M. L., De La Cuesta, B., Jack, D. W., Schlesinger, S. B., Valarezo, A., Burke, M. 2023; 120 (34): e2301061120

    Abstract

    Household electrification is thought to be an important part of a carbon-neutral future and could also have additional benefits to adopting households such as improved air quality. However, the effectiveness of specific electrification policies in reducing total emissions and boosting household livelihoods remains a crucial open question in both developed and developing countries. We investigated a transition of more than 750,000 households from gas to electric cookstoves-one of the most popular residential electrification strategies-in Ecuador following a program that promoted induction stoves and assessed its impacts on electricity consumption, greenhouse gas emissions, and health. We estimate that the program resulted in a 5% increase in total residential electricity consumption between 2015 and 2021. By offsetting a commensurate amount of cooking gas combustion, we find that the program likely reduced national greenhouse gas emissions, thanks in part to the country's electricity grid being 80% hydropower in later parts of the time period. Increased induction stove uptake was also associated with declines in all-cause and respiratory-related hospitalizations nationwide. These findings suggest that, when the electricity grid is largely powered by renewables, gas-to-induction cooking transitions represent a promising way of amplifying the health and climate cobenefits of net-carbon-zero policies.

    View details for DOI 10.1073/pnas.2301061120

    View details for PubMedID 37582122

  • Drought impacts on the electricity system, emissions, and air quality in the western United States. Proceedings of the National Academy of Sciences of the United States of America Qiu, M., Ratledge, N., Azevedo, I. M., Diffenbaugh, N. S., Burke, M. 2023; 120 (28): e2300395120

    Abstract

    The western United States has experienced severe drought in recent decades, and climate models project increased drought risk in the future. This increased drying could have important implications for the region's interconnected, hydropower-dependent electricity systems. Using power-plant level generation and emissions data from 2001 to 2021, we quantify the impacts of drought on the operation of fossil fuel plants and the associated impacts on greenhouse gas (GHG) emissions, air quality, and human health. We find that under extreme drought, electricity generation from individual fossil fuel plants can increase up to 65% relative to average conditions, mainly due to the need to substitute for reduced hydropower. Over 54% of this drought-induced generation is transboundary, with drought in one electricity region leading to net imports of electricity and thus increased pollutant emissions from power plants in other regions. These drought-induced emission increases have detectable impacts on local air quality, as measured by proximate pollution monitors. We estimate that the monetized costs of excess mortality and GHG emissions from drought-induced fossil generation are 1.2 to 2.5x the reported direct economic costs from lost hydro production and increased demand. Combining climate model estimates of future drying with stylized energy-transition scenarios suggests that these drought-induced impacts are likely to remain large even under aggressive renewables expansion, suggesting that more ambitious and targeted measures are needed to mitigate the emissions and health burden from the electricity sector during drought.

    View details for DOI 10.1073/pnas.2300395120

    View details for PubMedID 37410866

  • Global biomass fires and infant mortality. Proceedings of the National Academy of Sciences of the United States of America Pullabhotla, H. K., Zahid, M., Heft-Neal, S., Rathi, V., Burke, M. 2023; 120 (23): e2218210120

    Abstract

    Global outdoor biomass burning is a major contributor to air pollution, especially in low- and middle-income countries. Recent years have witnessed substantial changes in the extent of biomass burning, including large declines in Africa. However, direct evidence of the contribution of biomass burning to global health outcomes remains limited. Here, we use georeferenced data on more than 2 million births matched to satellite-derived burned area exposure to estimate the burden of biomass fires on infant mortality. We find that each additional square kilometer of burning is associated with nearly 2% higher infant mortality in nearby downwind locations. The share of infant deaths attributable to biomass fires has increased over time due to the rapid decline in other important causes of infant death. Applying our model estimates across harmonized district-level data covering 98% of global infant deaths, we find that exposure to outdoor biomass burning was associated with nearly 130,000 additional infant deaths per year globally over our 2004 to 2018 study period. Despite the observed decline in biomass burning in Africa, nearly 75% of global infant deaths due to burning still occur in Africa. While fully eliminating biomass burning is unlikely, we estimate that even achievable reductions-equivalent to the lowest observed annual burning in each location during our study period-could have avoided more than 70,000 infant deaths per year globally since 2004.

    View details for DOI 10.1073/pnas.2218210120

    View details for PubMedID 37253010

  • Antenatal wildfire smoke exposure and hypertensive disorders of pregnancy Waldrop, A. R., Blumenfeld, Y. J., Mayo, J. A., Panelli, D. M., Heft-Neal, S., Burke, M., Leonard, S. A., Shaw, G. M. MOSBY-ELSEVIER. 2023: S59-S60
  • Using machine learning to assess the livelihood impact of electricity access. Nature Ratledge, N., Cadamuro, G., de la Cuesta, B., Stigler, M., Burke, M. 2022; 611 (7936): 491-495

    Abstract

    In many regions of the world, sparse data on key economic outcomes inhibit the development, targeting and evaluation of public policy1,2. We demonstrate how advancements in satellite imagery and machine learning (ML) can help ameliorate these data and inference challenges. In the context of an expansion of the electrical grid across Uganda, we show how a combination of satellite imagery and computer vision can be used to develop local-level livelihood measurements appropriate for inferring the causal impact of electricity access on livelihoods. We then show how ML-based inference techniques deliver more reliable estimates of the causal impact of electrification than traditional alternatives when applied to these data. We estimate that grid access improves village-level asset wealth in rural Uganda by up to 0.15 standard deviations, more than doubling the growth rate during our study period relative to untreated areas. Our results provide country-scale evidence on the impact of grid-based infrastructure investment and our methods provide a low-cost, generalizable approach to future policy evaluation in data-sparse environments.

    View details for DOI 10.1038/s41586-022-05322-8

    View details for PubMedID 36385544

  • Lower test scores from wildfire smoke exposure NATURE SUSTAINABILITY Wen, J., Burke, M. 2022
  • Wildfire smoke exposure worsens students' learning outcomes NATURE SUSTAINABILITY Wen, J., Burke, M. 2022
  • Geographically resolved social cost of anthropogenic emissions accounting for both direct and climate-mediated effects. Science advances Burney, J., Persad, G., Proctor, J., Bendavid, E., Burke, M., Heft-Neal, S. 2022; 8 (38): eabn7307

    Abstract

    The magnitude and distribution of physical and societal impacts from long-lived greenhouse gases are insensitive to the emission source location; the same is not true for major coemitted short-lived pollutants such as aerosols. Here, we combine novel global climate model simulations with established response functions to show that a given aerosol emission from different regions produces divergent air quality and climate changes and associated human system impacts, both locally and globally. The marginal global damages to infant mortality, crop productivity, and economic growth from aerosol emissions and their climate effects differ by more than an order of magnitude depending on source region, with certain regions creating global external climate changes and impacts much larger than those felt locally. The complex distributions of aerosol-driven societal impacts emerge from geographically distinct and region-specific aerosol-climate interactions, estimation of which is enabled by the full Earth System Modeling Framework used here.

    View details for DOI 10.1126/sciadv.abn7307

    View details for PubMedID 36149961

  • Geographically resolved social cost of anthropogenic emissions accounting for both direct and climate-mediated effects SCIENCE ADVANCES Burney, J., Persad, G., Proctor, J., Bendavid, E., Burke, M., Heft-Neal, S. 2022; 8 (38)
  • Daily Local-Level Estimates of Ambient Wildfire Smoke PM2.5 for the Contiguous US. Environmental science & technology Childs, M. L., Li, J., Wen, J., Heft-Neal, S., Driscoll, A., Wang, S., Gould, C. F., Qiu, M., Burney, J., Burke, M. 2022

    Abstract

    Smoke from wildfires is a growing health risk across the US. Understanding the spatial and temporal patterns of such exposure and its population health impacts requires separating smoke-driven pollutants from non-smoke pollutants and a long time series to quantify patterns and measure health impacts. We develop a parsimonious and accurate machine learning model of daily wildfire-driven PM2.5 concentrations using a combination of ground, satellite, and reanalysis data sources that are easy to update. We apply our model across the contiguous US from 2006 to 2020, generating daily estimates of smoke PM2.5 over a 10 km-by-10 km grid and use these data to characterize levels and trends in smoke PM2.5. Smoke contributions to daily PM2.5 concentrations have increased by up to 5 mug/m3 in the Western US over the last decade, reversing decades of policy-driven improvements in overall air quality, with concentrations growing fastest for higher income populations and predominantly Hispanic populations. The number of people in locations with at least 1 day of smoke PM2.5 above 100 mug/m3 per year has increased 27-fold over the last decade, including nearly 25 million people in 2020 alone. Our data set can bolster efforts to comprehensively understand the drivers and societal impacts of trends and extremes in wildfire smoke.

    View details for DOI 10.1021/acs.est.2c02934

    View details for PubMedID 36134580

  • Exposures and behavioural responses to wildfire smoke. Nature human behaviour Burke, M., Heft-Neal, S., Li, J., Driscoll, A., Baylis, P., Stigler, M., Weill, J. A., Burney, J. A., Wen, J., Childs, M. L., Gould, C. F. 2022

    Abstract

    Pollution from wildfires constitutes a growing source of poor air quality globally. To protect health, governments largely rely on citizens to limit their own wildfire smoke exposures, but the effectiveness of this strategy is hard to observe. Using data from private pollution sensors, cell phones, social media posts and internet search activity, we find that during large wildfire smoke events, individuals in wealthy locations increasingly search for information about air quality and health protection, stay at home more and are unhappier. Residents of lower-income neighbourhoods exhibit similar patterns in searches for air quality information but not for health protection, spend less time at home and have more muted sentiment responses. During smoke events, indoor particulate matter (PM2.5) concentrations often remain 3-4* above health-based guidelines and vary by 20* between neighbouring households. Our results suggest that policy reliance on self-protection to mitigate smoke health risks will have modest and unequal benefits.

    View details for DOI 10.1038/s41562-022-01396-6

    View details for PubMedID 35798884

  • Upstream oil and gas production and ambient air pollution in California. The Science of the total environment Gonzalez, D. J., Francis, C. K., Shaw, G. M., Cullen, M. R., Baiocchi, M., Burke, M. 2022; 806 (Pt 1): 150298

    Abstract

    Prior studies have found that residential proximity to upstream oil and gas production is associated with increased risk of adverse health outcomes. Emissions of ambient air pollutants from oil and gas wells in the preproduction and production stages have been proposed as conferring risk of adverse health effects, but the extent of air pollutant emissions and resulting nearby pollution concentrations from wells is not clear.We examined the effects of upstream oil and gas preproduction (count of drilling sites) and production (total volume of oil and gas) activities on concentrations of five ambient air pollutants in California.We obtained data on approximately 1 million daily observations from 314 monitors in the EPA Air Quality System, 2006-2019, including daily concentrations of five routinely monitored ambient air pollutants: PM2.5, CO, NO2, O3, and VOCs. We obtained data on preproduction and production operations from Enverus and the California Geographic Energy Management Division (CalGEM) for all wells in the state. For each monitor and each day, we assessed exposure to upwind preproduction wells and total oil and gas production volume within 10 km. We used a panel regression approach in the analysis and fit adjusted fixed effects linear regression models for each pollutant, controlling for geographic, seasonal, temporal, and meteorological factors.We observed higher concentrations of PM2.5 and CO at monitors within 3 km of preproduction wells, NO2 at monitors at 1-2 km, and O3 at 2-4 km from the wells. Monitors with proximity to increased production volume observed higher concentrations of PM2.5, NO2, and VOCs within 1 km and higher O3 concentrations at 1-2 km. Results were robust to sensitivity analyses.Adjusting for geographic, meteorological, seasonal, and time-trending factors, we observed higher concentrations of ambient air pollutants at air quality monitors in proximity to preproduction wells within 4 km and producing wells within 2 km.

    View details for DOI 10.1016/j.scitotenv.2021.150298

    View details for PubMedID 34844318

  • Upstream oil and gas production and ambient air pollution in California SCIENCE OF THE TOTAL ENVIRONMENT Gonzalez, D. X., Francis, C. K., Shaw, G. M., Cullen, M. R., Baiocchi, M., Burke, M. 2022; 806
  • IS-Count: Large-Scale Object Counting from Satellite Images with Covariate-Based Importance Sampling Meng, C., Liu, E., Neiswanger, W., Song, J., Burke, M., Lobell, D., Ermon, S., Assoc Advancement Artificial Intelligence ASSOC ADVANCEMENT ARTIFICIAL INTELLIGENCE. 2022: 12034-12042
  • Associations between wildfire smoke exposure during pregnancy and risk of preterm birth in California. Environmental research Heft-Neal, S., Driscoll, A., Yang, W., Shaw, G., Burke, M. 2021: 111872

    Abstract

    There is limited population-scale evidence on the burden of exposure to wildfire smoke during pregnancy and its impacts on birth outcomes. In order to investigate this relationship, data on every singleton birth in California 2006-2012 were combined with satellite-based estimates of wildfire smoke plume boundaries and high-resolution gridded estimates of surface PM2.5 concentrations and a regression model was used to estimate associations with preterm birth risk. Results suggest that each additional day of exposure to any wildfire smoke during pregnancy was associated with an 0.49 % (95 % CI: 0.41-0.59 %) increase in risk of preterm birth (<37 weeks). At sample median smoke exposure (7 days) this translated to a 3.4 % increase in risk, relative to an unexposed mother. Estimates by trimester suggest stronger associations with exposure later in pregnancy and estimates by smoke intensity indicate that observed associations were driven by higher intensity smoke-days. Exposure to low intensity smoke-days had no association with preterm birth while an additional medium (smoke PM2.5 5-10 mug/m3) or high (smoke PM2.5 > 10 mug/m3) intensity smoke-day was associated with an 0.95 % (95 % CI: 0.47-1.42 %) and 0.82 % (95 % CI: 0.41-1.24 %) increase in preterm risk, respectively. In contrast to previous findings for other pollution types, neither exposure to smoke nor the relative impact of smoke on preterm birth differed by race/ethnicity or income in our sample. However, impacts differed greatly by baseline smoke exposure, with mothers in regions with infrequent smoke exposure experiencing substantially larger impacts from an additional smoke-day than mothers in regions where smoke is more common. We estimate 6,974 (95 % CI: 5,513-8,437) excess preterm births attributable to wildfire smoke exposure 2007-2012, accounting for 3.7 % of observed preterm births during this period. Our findings have important implications for understanding the costs of growing wildfire smoke exposure, and for understanding the benefits of smoke mitigation measures.

    View details for DOI 10.1016/j.envres.2021.111872

    View details for PubMedID 34403668

  • Historical warming has increased US crop insurance losses ENVIRONMENTAL RESEARCH LETTERS Diffenbaugh, N. S., Davenport, F., Burke, M. 2021; 16 (8)
  • Twice Is Nice: The Benefits of Two Ground Measures for Evaluating the Accuracy of Satellite-Based Sustainability Estimates REMOTE SENSING Lobell, D. B., Di Tommaso, S., Burke, M., Kilic, T. 2021; 13 (16)

    View details for DOI 10.3390/rs13163160

    View details for Web of Science ID 000690181500001

  • Scalable deep learning to identify brick kilns and aid regulatory capacity. Proceedings of the National Academy of Sciences of the United States of America Lee, J., Brooks, N. R., Tajwar, F., Burke, M., Ermon, S., Lobell, D. B., Biswas, D., Luby, S. P. 2021; 118 (17)

    Abstract

    Improving compliance with environmental regulations is critical for promoting clean environments and healthy populations. In South Asia, brick manufacturing is a major source of pollution but is dominated by small-scale, informal producers who are difficult to monitor and regulate-a common challenge in low-income settings. We demonstrate a low-cost, scalable approach for locating brick kilns in high-resolution satellite imagery from Bangladesh. Our approach identifies kilns with 94.2% accuracy and 88.7% precision and extracts the precise GPS coordinates of every brick kiln across Bangladesh. Using these estimates, we show that at least 12% of the population of Bangladesh (>18 million people) live within 1 km of a kiln and that 77% and 9% of kilns are (illegally) within 1 km of schools and health facilities, respectively. Finally, we show how kilns contribute up to 20.4 mug/[Formula: see text] of [Formula: see text] (particulate matter of a diameter less than 2.5 mum) in Dhaka when the wind blows from an unfavorable direction. We document inaccuracies and potential bias with respect to local regulations in the government data. Our approach demonstrates how machine learning and Earth observation can be combined to better understand the extent and implications of regulatory compliance in informal industry.

    View details for DOI 10.1073/pnas.2018863118

    View details for PubMedID 33888583

  • The effect of information about climate risk on property values. Proceedings of the National Academy of Sciences of the United States of America Hino, M., Burke, M. 2021; 118 (17)

    Abstract

    Floods and other climate hazards pose a widespread and growing threat to housing and infrastructure around the world. By reflecting climate risk in prices, markets can discourage excessive development in hazardous areas. However, the extent to which markets price these risks remains poorly understood. Here we measure the effect of information about flood risk contained in regulatory floodplain maps on residential property values in the United States. Using multiple empirical approaches and two decades of sales data covering the universe of homes in the United States, we find little evidence that housing markets fully price information about flood risk in aggregate. However, the price penalty is larger for commercial buyers and in markets where buyers are more risk aware, suggesting that policies to improve risk communication could influence market outcomes. Our findings indicate that houses in flood zones in the United States are currently overvalued by a total of $43.8 billion (95% confidence interval: $32.6 to $55.6 billion) based on the information in publicly available flood hazard maps alone, raising concerns about the stability of real estate markets as climate risks become more salient and severe.

    View details for DOI 10.1073/pnas.2003374118

    View details for PubMedID 33879604

  • Contribution of historical precipitation change to US flood damages. Proceedings of the National Academy of Sciences of the United States of America Davenport, F. V., Burke, M., Diffenbaugh, N. S. 2021; 118 (4)

    Abstract

    Precipitation extremes have increased across many regions of the United States, with further increases anticipated in response to additional global warming. Quantifying the impact of these precipitation changes on flood damages is necessary to estimate the costs of climate change. However, there is little empirical evidence linking changes in precipitation to the historically observed increase in flood losses. We use >6,600 reports of state-level flood damage to quantify the historical relationship between precipitation and flood damages in the United States. Our results show a significant, positive effect of both monthly and 5-d state-level precipitation on state-level flood damages. In addition, we find that historical precipitation changes have contributed approximately one-third of cumulative flood damages over 1988 to 2017 (primary estimate 36%; 95% CI 20 to 46%), with the cumulative impact of precipitation change totaling $73 billion (95% CI 39 to $91 billion). Further, climate models show that anthropogenic climate forcing has increased the probability of exceeding precipitation thresholds at the extremely wet quantiles that are responsible for most flood damages. Climate models project continued intensification of wet conditions over the next three decades, although a trajectory consistent with UN Paris Agreement goals significantly curbs that intensification. Taken together, our results quantify the contribution of precipitation trends to recent increases in flood damages, advance estimates of the costs associated with historical greenhouse gas emissions, and provide further evidence that lower levels of future warming are very likely to reduce financial losses relative to the current global warming trajectory.

    View details for DOI 10.1073/pnas.2017524118

    View details for PubMedID 33431652

  • The changing risk and burden of wildfire in the United States. Proceedings of the National Academy of Sciences of the United States of America Burke, M., Driscoll, A., Heft-Neal, S., Xue, J., Burney, J., Wara, M. 2021; 118 (2)

    Abstract

    Recent dramatic and deadly increases in global wildfire activity have increased attention on the causes of wildfires, their consequences, and how risk from wildfire might be mitigated. Here we bring together data on the changing risk and societal burden of wildfire in the United States. We estimate that nearly 50 million homes are currently in the wildland-urban interface in the United States, a number increasing by 1 million houses every 3 y. To illustrate how changes in wildfire activity might affect air pollution and related health outcomes, and how these linkages might guide future science and policy, we develop a statistical model that relates satellite-based fire and smoke data to information from pollution monitoring stations. Using the model, we estimate that wildfires have accounted for up to 25% of PM 2.5 (particulate matter with diameter <2.5 mum) in recent years across the United States, and up to half in some Western regions, with spatial patterns in ambient smoke exposure that do not follow traditional socioeconomic pollution exposure gradients. We combine the model with stylized scenarios to show that fuel management interventions could have large health benefits and that future health impacts from climate-change-induced wildfire smoke could approach projected overall increases in temperature-related mortality from climate change-but that both estimates remain uncertain. We use model results to highlight important areas for future research and to draw lessons for policy.

    View details for DOI 10.1073/pnas.2011048118

    View details for PubMedID 33431571

  • Using satellite imagery to understand and promote sustainable development. Science (New York, N.Y.) Burke, M., Driscoll, A., Lobell, D. B., Ermon, S. 2021; 371 (6535)

    Abstract

    Accurate and comprehensive measurements of a range of sustainable development outcomes are fundamental inputs into both research and policy. We synthesize the growing literature that uses satellite imagery to understand these outcomes, with a focus on approaches that combine imagery with machine learning. We quantify the paucity of ground data on key human-related outcomes and the growing abundance and improving resolution (spatial, temporal, and spectral) of satellite imagery. We then review recent machine learning approaches to model-building in the context of scarce and noisy training data, highlighting how this noise often leads to incorrect assessment of model performance. We quantify recent model performance across multiple sustainable development domains, discuss research and policy applications, explore constraints to future progress, and highlight research directions for the field.

    View details for DOI 10.1126/science.abe8628

    View details for PubMedID 33737462

  • Geography-Aware Self-Supervised Learning Ayush, K., Uzkent, B., Meng, C., Tanmay, K., Burke, M., Lobell, D., Ermon, S., IEEE IEEE. 2021: 10161-10170
  • Efficient Poverty Mapping from High Resolution Remote Sensing Images Ayush, K., Uzkent, B., Tanmay, K., Burke, M., Lobell, D., Ermon, S., Assoc Advancement Artificial Intelligence ASSOC ADVANCEMENT ARTIFICIAL INTELLIGENCE. 2021: 12-20
  • Predicting Livelihood Indicators from Community-Generated Street-Level Imagery Lee, J., Grosz, D., Uzkent, B., Zeng, S., Burke, M., Lobell, D., Ermon, S., Assoc Advancement Artificial Intelligence ASSOC ADVANCEMENT ARTIFICIAL INTELLIGENCE. 2021: 268-276
  • Quantifying the Effect of Precipitation on Landslide Hazard in Urbanized and Non-Urbanized Areas Geophysical Research Letters Johnston, E. C., Davenport, F. V., Wang, L., Caers, J. K., Muthukrishnan, S., Burke, M., Diffenbaugh, N. S. 2021; 48 (16)

    View details for DOI 10.1029/2021GL094038

  • Addressing Climate Change and Its Effects on Human Health: A Call to Action for Medical Schools. Academic medicine : journal of the Association of American Medical Colleges Goshua, A., Gomez, J., Erny, B., Burke, M., Luby, S., Sokolow, S., LaBeaud, A. D., Auerbach, P., Gisondi, M. A., Nadeau, K. 2020

    Abstract

    Human health is increasingly threatened by rapid and widespread changes in the environment and climate, including rising temperatures, air and water pollution, disease vector migration, floods, and droughts. In the United States, many medical schools, the American Medical Association, and the National Academy of Sciences have published calls for physicians and physicians-in-training to develop a basic knowledge of the science of climate change and an awareness of the associated health risks. The authors--all medical students and educators--argue for the expeditious redesign of medical school curricula to teach students to recognize, diagnose, and treat the many health conditions exacerbated by climate change as well as understanding public health issues. In this Invited Commentary, the authors briefly review the health impacts of climate change, examine current climate change course offerings and proposals, and describe the rationale for promptly and comprehensively including climate science education in medical school curricula. Efforts in training physicians now will benefit those physicians' communities, whose health will be impacted by a period of remarkable climate change. The bottom line is that the health effects of climate reality cannot be ignored, and people everywhere must adapt as quickly as possible.

    View details for DOI 10.1097/ACM.0000000000003861

    View details for PubMedID 33239537

  • The Economic Origins of Conflict in Africa JOURNAL OF POLITICAL ECONOMY McGuirk, E., Burke, M. 2020

    View details for DOI 10.1086/709993

    View details for Web of Science ID 000570151000001

  • The COVID-19 lockdowns: a window into the Earth System NATURE REVIEWS EARTH & ENVIRONMENT Diffenbaugh, N. S., Field, C. B., Appel, E. A., Azevedo, I. L., Baldocchi, D. D., Burke, M., Burney, J. A., Ciais, P., Davis, S. J., Fiore, A. M., Fletcher, S. M., Hertel, T. W., Horton, D. E., Hsiang, S. M., Jackson, R. B., Jin, X., Levi, M., Lobell, D. B., McKinley, G. A., Moore, F. C., Montgomery, A., Nadeau, K. C., Pataki, D. E., Randerson, J. T., Reichstein, M., Schnell, J. L., Seneviratne, S., Singh, D., Steiner, A. L., Wong-Parodi, G. 2020; 1 (9): 470-481
  • Directions for Research on Climate and Conflict. Earth's future Mach, K. J., Adger, W. N., Buhaug, H., Burke, M., Fearon, J. D., Field, C. B., Hendrix, C. S., Kraan, C. M., Maystadt, J., O'Loughlin, J., Roessler, P., Scheffran, J., Schultz, K. A., von Uexkull, N. 2020; 8 (7): e2020EF001532

    Abstract

    The potential links between climate and conflict are well studied, yet disagreement about the specific mechanisms and their significance for societies persists. Here, we build on assessment of the relationship between climate and organized armed conflict to define crosscutting priorities for future directions of research. They include (1) deepening insight into climate-conflict linkages and conditions under which they manifest, (2) ambitiously integrating research designs, (3) systematically exploring future risks and response options, responsive to ongoing decision-making, and (4) evaluating the effectiveness of interventions to manage climate-conflict links. The implications of this expanding scientific domain unfold in real time.

    View details for DOI 10.1029/2020EF001532

    View details for PubMedID 32715014

  • Dust pollution from the Sahara and African infant mortality NATURE SUSTAINABILITY Heft-Neal, S., Burney, J., Bendavid, E., Voss, K. K., Burke, M. 2020
  • Reply to: Temporal displacement, adaptation and the effect of climate on suicide rates NATURE CLIMATE CHANGE Burke, M., Gonzalez, F., Baylis, P., Heft-Neal, S., Baysan, C., Hsiang, S. 2020
  • EYES IN THE SKY, BOOTS ON THE GROUND: ASSESSING SATELLITE- AND GROUND-BASED APPROACHES TO CROP YIELD MEASUREMENT AND ANALYSIS AMERICAN JOURNAL OF AGRICULTURAL ECONOMICS Lobell, D. B., Azzari, G., Burke, M., Gourlay, S., Jin, Z., Kilic, T., Murray, S. 2020; 102 (1): 202–19
  • Using publicly available satellite imagery and deep learning to understand economic well-being in Africa. Nature communications Yeh, C. n., Perez, A. n., Driscoll, A. n., Azzari, G. n., Tang, Z. n., Lobell, D. n., Ermon, S. n., Burke, M. n. 2020; 11 (1): 2583

    Abstract

    Accurate and comprehensive measurements of economic well-being are fundamental inputs into both research and policy, but such measures are unavailable at a local level in many parts of the world. Here we train deep learning models to predict survey-based estimates of asset wealth across ~ 20,000 African villages from publicly-available multispectral satellite imagery. Models can explain 70% of the variation in ground-measured village wealth in countries where the model was not trained, outperforming previous benchmarks from high-resolution imagery, and comparison with independent wealth measurements from censuses suggests that errors in satellite estimates are comparable to errors in existing ground data. Satellite-based estimates can also explain up to 50% of the variation in district-aggregated changes in wealth over time, with daytime imagery particularly useful in this task. We demonstrate the utility of satellite-based estimates for research and policy, and demonstrate their scalability by creating a wealth map for Africa's most populous country.

    View details for DOI 10.1038/s41467-020-16185-w

    View details for PubMedID 32444658

  • Sight for Sorghums: Comparisons of Satellite- and Ground-Based Sorghum Yield Estimates in Mali REMOTE SENSING Lobell, D. B., Di Tommaso, S., You, C., Djima, I., Burke, M., Kilic, T. 2020; 12 (1)

    View details for DOI 10.3390/rs12010100

    View details for Web of Science ID 000515391700100

  • Flood Size Increases Nonlinearly Across the Western United States in Response to Lower Snow-Precipitation Ratios WATER RESOURCES RESEARCH Davenport, F. V., Herrera-Estrada, J. E., Burke, M., Diffenbaugh, N. S. 2020; 56 (1)
  • Oil and gas production and spontaneous preterm birth in the San Joaquin Valley, CA: A case-control study. Environmental epidemiology (Philadelphia, Pa.) Gonzalez, D. J., Sherris, A. R., Yang, W. n., Stevenson, D. K., Padula, A. M., Baiocchi, M. n., Burke, M. n., Cullen, M. R., Shaw, G. M. 2020; 4 (4): e099

    Abstract

    Recent studies report an association between preterm birth and exposure to unconventional oil and gas wells. There has been limited previous study on exposure to conventional wells, which are common in California. Our objective was to determine whether exposure to well sites was associated with increased odds of spontaneous preterm birth (delivery at <37 weeks).We conducted a case-control study using data on 27,913 preterm birth cases and 197,461 term birth controls. All births were without maternal comorbidities and were located in the San Joaquin Valley, CA, between 1998 and 2011. We obtained data for 83,559 wells in preproduction or production during the study period. We assessed exposure using inverse distance-squared weighting and, for each birth and trimester, we assigned an exposure tertile. Using logistic regression, we estimated adjusted odds ratios (ORs) for the association between exposure to well sites and preterm birth at 20-27, 28-31, and 32-36 weeks.We observed increased ORs for preterm birth with high exposure to wells in the first and second trimesters for births delivered at ≤31 weeks (adjusted ORs, 1.08-1.14). In stratified analyses, the associations were confined to births to Hispanic and non-Hispanic Black women and to women with ≤12 years of educational attainment. In a secondary analysis, we found evidence that exposure to wells in preproduction is associated with higher concentrations of particulate matter.We found evidence that exposure to oil and gas well sites is associated with increased risk of spontaneous preterm birth.

    View details for DOI 10.1097/EE9.0000000000000099

    View details for PubMedID 32832838

    View details for PubMedCentralID PMC7423522

  • Non-economic factors in violence: Evidence from organized crime, suicides and climate in Mexico JOURNAL OF ECONOMIC BEHAVIOR & ORGANIZATION Baysan, C., Burke, M., Gonzalez, F., Hsiang, S., Miguel, E. 2019; 168: 434–52
  • Smallholder maize area and yield mapping at national scales with Google Earth Engine REMOTE SENSING OF ENVIRONMENT Jin, Z., Azzari, G., You, C., Di Tommaso, S., Aston, S., Burke, M., Lobell, D. B. 2019; 228: 115–28
  • Global warming has increased global economic inequality PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA Diffenbaugh, N. S., Burke, M. 2019; 116 (20): 9808–13
  • SELL LOW AND BUY HIGH: ARBITRAGE AND LOCAL PRICE EFFECTS IN KENYAN MARKETS QUARTERLY JOURNAL OF ECONOMICS Burke, M., Bergquist, L., Miguel, E. 2019; 134 (2): 785–842

    View details for DOI 10.1093/qje/qjy034

    View details for Web of Science ID 000489162100005

  • Global warming has increased global economic inequality. Proceedings of the National Academy of Sciences of the United States of America Diffenbaugh, N. S., Burke, M. 2019

    Abstract

    Understanding the causes of economic inequality is critical for achieving equitable economic development. To investigate whether global warming has affected the recent evolution of inequality, we combine counterfactual historical temperature trajectories from a suite of global climate models with extensively replicated empirical evidence of the relationship between historical temperature fluctuations and economic growth. Together, these allow us to generate probabilistic country-level estimates of the influence of anthropogenic climate forcing on historical economic output. We find very high likelihood that anthropogenic climate forcing has increased economic inequality between countries. For example, per capita gross domestic product (GDP) has been reduced 17-31% at the poorest four deciles of the population-weighted country-level per capita GDP distribution, yielding a ratio between the top and bottom deciles that is 25% larger than in a world without global warming. As a result, although between-country inequality has decreased over the past half century, there is 90% likelihood that global warming has slowed that decrease. The primary driver is the parabolic relationship between temperature and economic growth, with warming increasing growth in cool countries and decreasing growth in warm countries. Although there is uncertainty in whether historical warming has benefited some temperate, rich countries, for most poor countries there is >90% likelihood that per capita GDP is lower today than if global warming had not occurred. Thus, our results show that, in addition to not sharing equally in the direct benefits of fossil fuel use, many poor countries have been significantly harmed by the warming arising from wealthy countries' energy consumption.

    View details for PubMedID 31010922

  • Back to the root causes of war: food shortages Reply LANCET Wagner, Z., Heft-Neal, S., Bhutta, Z. A., Black, R. E., Burke, M., Bendavid, E. 2019; 393 (10175): 982
  • Back to the root causes of war: food shortages - Authors' reply. Lancet (London, England) Wagner, Z., Heft-Neal, S., Bhutta, Z. A., Black, R. E., Burke, M., Bendavid, E. 2019; 393 (10175): 982

    View details for PubMedID 30860044

  • Reply to Rosen: Temperature-growth relationship is robust. Proceedings of the National Academy of Sciences of the United States of America Diffenbaugh, N. S., Burke, M. n. 2019

    View details for DOI 10.1073/pnas.1908772116

    View details for PubMedID 31375623

  • Mapping Missing Population in Rural India: A Deep Learning Approach with Satellite Imagery Hu, W., Patel, J., Robert, Z., Novosad, P., Asher, S., Tang, Z., Burke, M., Lobell, D., Ermon, S., Assoc Comp Machinery ASSOC COMPUTING MACHINERY. 2019: 353–59
  • Women and children living in areas of armed conflict in Africa: a geospatial analysis of mortality and orphanhood. The Lancet. Global health Wagner, Z. n., Heft-Neal, S. n., Wise, P. H., Black, R. E., Burke, M. n., Boerma, T. n., Bhutta, Z. A., Bendavid, E. n. 2019

    Abstract

    The population effects of armed conflict on non-combatant vulnerable populations are incompletely understood. We aimed to study the effects of conflict on mortality among women of childbearing age (15-49 years) and on orphanhood among children younger than 15 years in Africa.We tested the extent to which mortality among women aged 15-49 years, and orphanhood among children younger than 15 years, increased in response to nearby armed conflict in Africa. Data on location, timing, and intensity of armed conflicts were obtained from the Uppsala Conflict Data Program, and data on the location, timing, and outcomes of women and children from Demographic and Health Surveys done in 35 African countries from 1990 to 2016. Mortality among women was obtained from sibling survival data. We used cluster-area fixed-effects regression models to compare survival of women during periods of nearby conflict (within 50 km) to survival of women in the same area during times without conflict. We used similar methods to examine the extent to which children living near armed conflicts are at increased risk of becoming orphans. We examined the effects of varying conflict intensity using number of direct battle deaths and duration of consecutive conflict exposure.We analysed data on 1 629 352 women (19 286 387 person-years), of which 103 011 (6·3%) died (534·1 deaths per 100 000 women-years), and 2 354 041 children younger than 15 years, of which 204 276 (8·7%) had lost a parent. On average, conflict within 50 km increased women's mortality by 112 deaths per 100 000 person-years (95% CI 97-128; a 21% increase above baseline), and the probability that a child has lost at least one parent by 6·0% (95% CI 3-8). This effect was driven by high-intensity conflicts: exposure to the highest (tenth) decile conflict in terms of conflict-related deaths increased the probability of female mortality by 202% (187-218) and increased the likelihood of orphanhood by 42% compared with a conflict-free period. Among the conflict-attributed deaths, 10% were due to maternal mortality.African women of childbearing age are at a substantially increased risk of death from nearby high-intensity armed conflicts. Children exposed to conflict are analogously at increased risk of becoming orphans. This work fills gaps in literature on the harmful effects of armed conflict on non-combatants and highlights the need for humanitarian interventions to protect vulnerable populations.Bill & Melinda Gates Foundation to the BRANCH Consortium.

    View details for DOI 10.1016/S2214-109X(19)30407-3

    View details for PubMedID 31669039

  • Predicting Economic Development using Geolocated Wikipedia Articles Sheehan, E., Meng, C., Tan, M., Uzkent, B., Jean, N., Burke, M., Lobell, D., Ermon, S., Assoc Comp Machinery ASSOC COMPUTING MACHINERY. 2019: 2698–2706
  • Climate as a risk factor for armed conflict. Nature Mach, K. J., Kraan, C. M., Adger, W. N., Buhaug, H. n., Burke, M. n., Fearon, J. D., Field, C. B., Hendrix, C. S., Maystadt, J. F., O'Loughlin, J. n., Roessler, P. n., Scheffran, J. n., Schultz, K. A., von Uexkull, N. n. 2019

    Abstract

    Research findings on the relationship between climate and conflict are diverse and contested. Here we assess the current understanding of the relationship between climate and conflict, based on the structured judgments of experts from diverse disciplines. These experts agree that climate has affected organized armed conflict within countries. However, other drivers, such as low socioeconomic development and low capabilities of the state, are judged to be substantially more influential, and the mechanisms of climate-conflict linkages remain a key uncertainty. Intensifying climate change is estimated to increase future risks of conflict.

    View details for DOI 10.1038/s41586-019-1300-6

    View details for PubMedID 31189956

  • Armed conflict and child mortality in Africa: a geospatial analysis. Lancet (London, England) Wagner, Z., Heft-Neal, S., Bhutta, Z. A., Black, R. E., Burke, M., Bendavid, E. 2018

    Abstract

    BACKGROUND: A substantial portion of child deaths in Africa take place in countries with recent history of armed conflict and political instability. However, the extent to which armed conflict is an important cause of child mortality, especially in Africa, remains unknown.METHODS: We matched child survival with proximity to armed conflict using information in the Uppsala Conflict Data Program Georeferenced Events Dataset on the location and intensity of armed conflict from 1995 to 2015 together with the location, timing, and survival of infants younger than 1 year (primary outcome) in 35 African countries. We measured the increase in mortality risk for infants exposed to armed conflicts within 50 km in the year of birth and, to study conflicts' extended health risks, up to 250 km away and 10 years before birth. We also examined the effects of conflicts of varying intensity and chronicity (conflicts lasting several years), and effect heterogeneity by residence and sex of the child. We then estimated the number and portion of deaths of infants younger than 1 year related to conflict.FINDINGS: We identified 15 441 armed conflict events that led to 968 444 combat-related deaths and matched these data with 1·99 million births and 133 361 infant deaths (infant mortality of 67 deaths per 1000 births) between 1995 and 2015. A child born within 50 km of an armed conflict had a risk of dying before reaching age 1 year of 5·2 per 1000 births higher than being born in the same region during periods without conflict (95% CI 3·7-6·7; a 7·7% increase above baseline). This increased risk of dying ranged from a 3·0% increase for armed conflicts with one to four deaths to a 26·7% increase for armed conflicts with more than 1000 deaths. We find evidence of increased mortality risk from an armed conflict up to 100 km away, and for 8 years after conflicts, with cumulative increase in infant mortality two to four times higher than the contemporaneous increase. In the entire continent, the number of infant deaths related to conflict from 1995 to 2015 was between 3·2 and 3·6 times the number of direct deaths from armed conflicts.INTERPRETATION: Armed conflict substantially and persistently increases infant mortality in Africa, with effect sizes on a scale with malnutrition and several times greater than existing estimates of the mortality burden of conflict. The toll of conflict on children, who are presumably not combatants, underscores the indirect toll of conflict on civilian populations, and the importance of developing interventions to address child health in areas of conflict.FUNDING: The Doris Duke Charitable Foundation, and the Centre for Global Child Health at the Hospital for Sick Children.

    View details for PubMedID 30173907

  • Estimating global agricultural effects of geoengineering using volcanic eruptions. Nature Proctor, J., Hsiang, S., Burney, J., Burke, M., Schlenker, W. 2018

    Abstract

    Solar radiation management is increasingly considered to be an option for managing global temperatures1,2, yet the economic effects of ameliorating climatic changes by scattering sunlight back to space remain largely unknown3. Although solar radiation management may increase crop yields by reducing heat stress4, the effects of concomitant changes in available sunlight have never been empirically estimated. Here we use the volcanic eruptions that inspired modern solar radiation management proposals as natural experiments to provide the first estimates, to our knowledge, of how the stratospheric sulfate aerosols created by the eruptions of El Chichon and Mount Pinatubo altered the quantity and quality of global sunlight, and how these changes in sunlight affected global crop yields. We find that the sunlight-mediated effect of stratospheric sulfate aerosols on yields is negative for both C4 (maize) and C3 (soy, rice and wheat) crops. Applying our yield model to a solar radiation management scenario based on stratospheric sulfate aerosols, we find that projected mid-twenty-first century damages due to scattering sunlight caused by solar radiation management are roughly equal in magnitude to benefits from cooling. This suggests that solar radiation management-if deployed using stratospheric sulfate aerosols similar to those emitted by the volcanic eruptions it seeks to mimic-would, on net, attenuate little of the global agricultural damage from climate change. Our approach could be extended to study the effects of solar radiation management on other global systems, such as human health or ecosystem function.

    View details for PubMedID 30089909

  • Robust relationship between air quality and infant mortality in Africa NATURE Heft-Neal, S., Burney, J., Bendavid, E., Burke, M. 2018; 559 (7713): 254-+
  • Anticipated burden and mitigation of carbon-dioxide-induced nutritional deficiencies and related diseases: A simulation modeling study. PLoS medicine Weyant, C., Brandeau, M. L., Burke, M., Lobell, D. B., Bendavid, E., Basu, S. 2018; 15 (7): e1002586

    Abstract

    BACKGROUND: Rising atmospheric carbon dioxide concentrations are anticipated to decrease the zinc and iron concentrations of crops. The associated disease burden and optimal mitigation strategies remain unknown. We sought to understand where and to what extent increasing carbon dioxide concentrations may increase the global burden of nutritional deficiencies through changes in crop nutrient concentrations, and the effects of potential mitigation strategies.METHODS AND FINDINGS: For each of 137 countries, we incorporated estimates of climate change, crop nutrient concentrations, dietary patterns, and disease risk into a microsimulation model of zinc and iron deficiency. These estimates were obtained from the Intergovernmental Panel on Climate Change, US Department of Agriculture, Statistics Division of the Food and Agriculture Organization of the United Nations, and Global Burden of Disease Project, respectively. In the absence of increasing carbon dioxide concentrations, we estimated that zinc and iron deficiencies would induce 1,072.9 million disability-adjusted life years (DALYs) globally over the period 2015 to 2050 (95% credible interval [CrI]: 971.1-1,167.7). In the presence of increasing carbon dioxide concentrations, we estimated that decreasing zinc and iron concentrations of crops would induce an additional 125.8 million DALYs globally over the same period (95% CrI: 113.6-138.9). This carbon-dioxide-induced disease burden is projected to disproportionately affect nations in the World Health Organization's South-East Asia and African Regions (44.0 and 28.5 million DALYs, respectively), which already have high existing disease burdens from zinc and iron deficiencies (364.3 and 299.5 million DALYs, respectively), increasing global nutritional inequalities. A climate mitigation strategy such as the Paris Agreement (an international agreement to keep global temperatures within 2°C of pre-industrial levels) would be expected to avert 48.2% of this burden (95% CrI: 47.8%-48.5%), while traditional public health interventions including nutrient supplementation and disease control programs would be expected to avert 26.6% of the burden (95% CrI: 23.8%-29.6%). Of the traditional public health interventions, zinc supplementation would be expected to avert 5.5%, iron supplementation 15.7%, malaria mitigation 3.2%, pneumonia mitigation 1.6%, and diarrhea mitigation 0.5%. The primary limitations of the analysis include uncertainty regarding how food consumption patterns may change with climate, how disease mortality rates will change over time, and how crop zinc and iron concentrations will decline from those at present to those in 2050.CONCLUSIONS: Effects of increased carbon dioxide on crop nutrient concentrations are anticipated to exacerbate inequalities in zinc and iron deficiencies by 2050. Proposed Paris Agreement strategies are expected to be more effective than traditional public health measures to avert the increased inequality.

    View details for PubMedID 29969442

  • Anticipated burden and mitigation of carbondioxide-induced nutritional deficiencies and related diseases: A simulation modeling study PLOS MEDICINE Weyant, C., Brandeau, M. L., Burke, M., Lobell, D. B., Bendavid, E., Basu, S. 2018; 15 (7)
  • Comment on "Food Abundance and Violent Conflict in Africa" Discussion AMERICAN JOURNAL OF AGRICULTURAL ECONOMICS Burke, M. 2018; 100 (4): 1007–9
  • Robust relationship between air quality and infant mortality in Africa. Nature Heft-Neal, S., Burney, J., Bendavid, E., Burke, M. 2018

    Abstract

    Poor air quality is thought to be an important mortality risk factor globally1-3, but there is little direct evidence from the developing world on how mortality risk varies with changing exposure to ambient particulate matter. Current global estimates apply exposure-response relationships that have been derived mostly from wealthy, mid-latitude countries to spatial population data 4 , and these estimates remain unvalidated across large portions of the globe. Here we combine household survey-based information on the location and timing of nearly 1million births across sub-Saharan Africa with satellite-based estimates 5 of exposure to ambient respirable particulate matter with an aerodynamic diameter less than 2.5mum (PM2.5) to estimate the impact of air quality on mortality rates among infants in Africa. We find that a 10mugm-3 increase in PM2.5 concentration is associated with a 9% (95% confidence interval, 4-14%) rise in infant mortality across the dataset. This effect has not declined over the last 15 years and does not diminish with higher levels of household wealth. Our estimates suggest that PM2.5 concentrations above minimum exposure levels were responsible for 22% (95% confidence interval, 9-35%) of infant deaths in our 30 study countries and led to 449,000 (95% confidence interval, 194,000-709,000) additional deaths of infants in 2015, an estimate that is more than three times higher than existing estimates that attribute death of infants to poor air quality for these countries2,6. Upward revision of disease-burden estimates in the studied countries in Africa alone would result in a doubling of current estimates of global deaths of infants that are associated with air pollution, and modest reductions in African PM2.5 exposures are predicted to have health benefits to infants that are larger than most known health interventions.

    View details for PubMedID 29950722

  • Large potential reduction in economic damages under UN mitigation targets NATURE Burke, M., Davis, W., Diffenbaugh, N. S. 2018; 557 (7706): 549-+

    Abstract

    International climate change agreements typically specify global warming thresholds as policy targets 1 , but the relative economic benefits of achieving these temperature targets remain poorly understood2,3. Uncertainties include the spatial pattern of temperature change, how global and regional economic output will respond to these changes in temperature, and the willingness of societies to trade present for future consumption. Here we combine historical evidence 4 with national-level climate 5 and socioeconomic 6 projections to quantify the economic damages associated with the United Nations (UN) targets of 1.5 °C and 2 °C global warming, and those associated with current UN national-level mitigation commitments (which together approach 3 °C warming 7 ). We find that by the end of this century, there is a more than 75% chance that limiting warming to 1.5 °C would reduce economic damages relative to 2 °C, and a more than 60% chance that the accumulated global benefits will exceed US$20 trillion under a 3% discount rate (2010 US dollars). We also estimate that 71% of countries-representing 90% of the global population-have a more than 75% chance of experiencing reduced economic damages at 1.5 °C, with poorer countries benefiting most. Our results could understate the benefits of limiting warming to 1.5 °C if unprecedented extreme outcomes, such as large-scale sea level rise 8 , occur for warming of 2 °C but not for warming of 1.5 °C. Inclusion of other unquantified sources of uncertainty, such as uncertainty in secular growth rates beyond that contained in existing socioeconomic scenarios, could also result in less precise impact estimates. We find considerably greater reductions in global economic output beyond 2 °C. Relative to a world that did not warm beyond 2000-2010 levels, we project 15%-25% reductions in per capita output by 2100 for the 2.5-3 °C of global warming implied by current national commitments 7 , and reductions of more than 30% for 4 °C warming. Our results therefore suggest that achieving the 1.5 °C target is likely to reduce aggregate damages and lessen global inequality, and that failing to meet the 2 °C target is likely to increase economic damages substantially.

    View details for PubMedID 29795251

  • Climate and conflict: no stigma NATURE Hsiang, S., Burke, M. 2018; 555 (7698): 587
  • Higher temperatures increase suicide rates in the United States and Mexico Nature Climate Change Burke, M., González, F., Baylis, P., Heft-Neal, S., Baysan, C., Basu, S., Hsiang, S. 2018; 8 (8): 723--729
  • Infrastructure Quality Assessment in Africa using Satellite Imagery and Deep Learning Oshri, B., Hu, A., Adelson, P., Chen, X., Dupas, P., Weinstein, J., Burke, M., Lobell, D., Ermon, S., ACM ASSOC COMPUTING MACHINERY. 2018: 616–25
  • Satellite-based assessment of yield variation and its determinants in smallholder African systems. Proceedings of the National Academy of Sciences of the United States of America Burke, M., Lobell, D. B. 2017; 114 (9): 2189-2194

    Abstract

    The emergence of satellite sensors that can routinely observe millions of individual smallholder farms raises possibilities for monitoring and understanding agricultural productivity in many regions of the world. Here we demonstrate the potential to track smallholder maize yield variation in western Kenya, using a combination of 1-m Terra Bella imagery and intensive field sampling on thousands of fields over 2 y. We find that agreement between satellite-based and traditional field survey-based yield estimates depends significantly on the quality of the field-based measures, with agreement highest ([Formula: see text] up to 0.4) when using precise field measures of plot area and when using larger fields for which rounding errors are smaller. We further show that satellite-based measures are able to detect positive yield responses to fertilizer and hybrid seed inputs and that the inferred responses are statistically indistinguishable from estimates based on survey-based yields. These results suggest that high-resolution satellite imagery can be used to make predictions of smallholder agricultural productivity that are roughly as accurate as the survey-based measures traditionally used in research and policy applications, and they indicate a substantial near-term potential to quickly generate useful datasets on productivity in smallholder systems, even with minimal or no field training data. Such datasets could rapidly accelerate learning about which interventions in smallholder systems have the most positive impact, thus enabling more rapid transformation of rural livelihoods.

    View details for DOI 10.1073/pnas.1616919114

    View details for PubMedID 28202728

    View details for PubMedCentralID PMC5338538

  • Using remotely sensed temperature to estimate climate response functions ENVIRONMENTAL RESEARCH LETTERS Heft-Neal, S., Lobell, D. B., Burke, M. 2017; 12 (1)
  • Sources of variation in under-5 mortality across sub-Saharan Africa: a spatial analysis. The Lancet. Global health Burke, M., Heft-Neal, S., Bendavid, E. 2016

    Abstract

    Detailed spatial understanding of levels and trends in under-5 mortality is needed to improve the targeting of interventions to the areas of highest need, and to understand the sources of variation in mortality. To improve this understanding, we analysed local-level information on child mortality across sub-Saharan Africa between 1980-2010.We used data from 82 Demographic and Health Surveys in 28 sub-Saharan African countries, including the location and timing of 3·24 million childbirths and 393 685 deaths, to develop high-resolution spatial maps of under-5 mortality in the 1980s, 1990s, and 2000s. These estimates were at a resolution of 0·1 degree latitude by 0·1 degree longitude (roughly 10 km × 10 km). We then analysed this spatial information to distinguish within-country versus between-country sources of variation in mortality, to examine the extent to which declines in mortality have been accompanied by convergence in the distribution of mortality, and to study localised drivers of mortality differences, including temperature, malaria burden, and conflict.In our sample of sub-Saharan African countries from the 1980s to the 2000s, within-country differences in under-5 mortality accounted for 74-78% of overall variation in under-5 mortality across space and over time. Mortality differed significantly across only 8-15% of country borders, supporting the role of local, rather than national, factors in driving mortality patterns. We found that by the end of the study period, 23% of the eligible children in the study countries continue to live in mortality hotspots-areas where, if current trends continue, the Sustainable Developent Goals mortality targets will not be met. In multivariate analysis, within-country mortality levels at each pixel were significantly related to local temperature, malaria burden, and recent history of conflict.Our findings suggest that sub-national determinants explain a greater portion of under-5 mortality than do country-level characteristics. Sub-national measures of child mortality could provide a more accurate, and potentially more actionable, portrayal of where and why children are still dying than can national statistics.The Stanford Woods Institute for the Environment.

    View details for DOI 10.1016/S2214-109X(16)30212-1

    View details for PubMedID 27793587

  • Combining satellite imagery and machine learning to predict poverty. Science Jean, N., Burke, M., Xie, M., Davis, W. M., Lobell, D. B., Ermon, S. 2016; 353 (6301): 790-794

    Abstract

    Reliable data on economic livelihoods remain scarce in the developing world, hampering efforts to study these outcomes and to design policies that improve them. Here we demonstrate an accurate, inexpensive, and scalable method for estimating consumption expenditure and asset wealth from high-resolution satellite imagery. Using survey and satellite data from five African countries--Nigeria, Tanzania, Uganda, Malawi, and Rwanda--we show how a convolutional neural network can be trained to identify image features that can explain up to 75% of the variation in local-level economic outcomes. Our method, which requires only publicly available data, could transform efforts to track and target poverty in developing countries. It also demonstrates how powerful machine learning techniques can be applied in a setting with limited training data, suggesting broad potential application across many scientific domains.

    View details for DOI 10.1126/science.aaf7894

    View details for PubMedID 27540167

  • Adaptation to Climate Change: Evidence from US Agriculture AMERICAN ECONOMIC JOURNAL-ECONOMIC POLICY Burke, M., Emerick, K. 2016; 8 (3): 106-140
  • Global non-linear effect of temperature on economic production NATURE Burke, M., Hsiang, S. M., Miguel, E. 2015; 527 (7577): 235-?

    Abstract

    Growing evidence demonstrates that climatic conditions can have a profound impact on the functioning of modern human societies, but effects on economic activity appear inconsistent. Fundamental productive elements of modern economies, such as workers and crops, exhibit highly non-linear responses to local temperature even in wealthy countries. In contrast, aggregate macroeconomic productivity of entire wealthy countries is reported not to respond to temperature, while poor countries respond only linearly. Resolving this conflict between micro and macro observations is critical to understanding the role of wealth in coupled human-natural systems and to anticipating the global impact of climate change. Here we unify these seemingly contradictory results by accounting for non-linearity at the macro scale. We show that overall economic productivity is non-linear in temperature for all countries, with productivity peaking at an annual average temperature of 13 °C and declining strongly at higher temperatures. The relationship is globally generalizable, unchanged since 1960, and apparent for agricultural and non-agricultural activity in both rich and poor countries. These results provide the first evidence that economic activity in all regions is coupled to the global climate and establish a new empirical foundation for modelling economic loss in response to climate change, with important implications. If future adaptation mimics past adaptation, unmitigated warming is expected to reshape the global economy by reducing average global incomes roughly 23% by 2100 and widening global income inequality, relative to scenarios without climate change. In contrast to prior estimates, expected global losses are approximately linear in global mean temperature, with median losses many times larger than leading models indicate.

    View details for DOI 10.1038/nature15725

    View details for Web of Science ID 000364396700045

    View details for PubMedID 26503051

  • INCORPORATING CLIMATE UNCERTAINTY INTO ESTIMATES OF CLIMATE CHANGE IMPACTS REVIEW OF ECONOMICS AND STATISTICS Burke, M., Dykema, J., Lobell, D. B., Miguel, E., Satyanath, S. 2015; 97 (2): 461-471
  • Climate and Conflict ANNUAL REVIEW OF ECONOMICS, VOL 7 Burke, M., Hsiang, S. M., Miguel, E. 2015; 7: 577-?
  • Reconciling climate-conflict meta-analyses: reply to Buhaug et al. CLIMATIC CHANGE Hsiang, S. M., Burke, M., Miguel, E. 2014; 127 (3-4): 399-405
  • Climate, conflict, and social stability: what does the evidence say? CLIMATIC CHANGE Hsiang, S. M., Burke, M. 2014; 123 (1): 39-55
  • Quantifying the influence of climate on human conflict. Science Hsiang, S. M., Burke, M., Miguel, E. 2013; 341 (6151): 1235367-?

    Abstract

    A rapidly growing body of research examines whether human conflict can be affected by climatic changes. Drawing from archaeology, criminology, economics, geography, history, political science, and psychology, we assemble and analyze the 60 most rigorous quantitative studies and document, for the first time, a striking convergence of results. We find strong causal evidence linking climatic events to human conflict across a range of spatial and temporal scales and across all major regions of the world. The magnitude of climate's influence is substantial: for each one standard deviation (1σ) change in climate toward warmer temperatures or more extreme rainfall, median estimates indicate that the frequency of interpersonal violence rises 4% and the frequency of intergroup conflict rises 14%. Because locations throughout the inhabited world are expected to warm 2σ to 4σ by 2050, amplified rates of human conflict could represent a large and critical impact of anthropogenic climate change.

    View details for DOI 10.1126/science.1235367

    View details for PubMedID 24031020

  • On the use of statistical models to predict crop yield responses to climate change AGRICULTURAL AND FOREST METEOROLOGY Lobell, D. B., Burke, M. B. 2010; 150 (11): 1443-1452
  • The poverty implications of climate-induced crop yield changes by 2030 GLOBAL ENVIRONMENTAL CHANGE-HUMAN AND POLICY DIMENSIONS Hertel, T. W., Burke, M. B., Lobell, D. B. 2010; 20 (4): 577-585
  • Solar-powered drip irrigation enhances food security in the Sudano-Sahel PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA Burney, J., Woltering, L., Burke, M., Naylor, R., Pasternak, D. 2010; 107 (5): 1848-1853

    Abstract

    Meeting the food needs of Africa's growing population over the next half-century will require technologies that significantly improve rural livelihoods at minimal environmental cost. These technologies will likely be distinct from those of the Green Revolution, which had relatively little impact in sub-Saharan Africa; consequently, few such interventions have been rigorously evaluated. This paper analyzes solar-powered drip irrigation as a strategy for enhancing food security in the rural Sudano-Sahel region of West Africa. Using a matched-pair comparison of villages in northern Benin (two treatment villages, two comparison villages), and household survey and field-level data through the first year of harvest in those villages, we find that solar-powered drip irrigation significantly augments both household income and nutritional intake, particularly during the dry season, and is cost effective compared to alternative technologies.

    View details for DOI 10.1073/pnas.0909678107

    View details for Web of Science ID 000274296300011

    View details for PubMedID 20080616

    View details for PubMedCentralID PMC2806882

  • Impacts of El Nino-Southern Oscillation events on China's rice production JOURNAL OF GEOGRAPHICAL SCIENCES Deng Xiangzheng, X. Z., Huang Jikun, J. K., Qiao Fangbin, F. B., Naylor, R. L., Falcon, W. P., Burke, M., Rozelle, S., Battisti, D. 2010; 20 (1): 3-16
  • Warming increases the risk of civil war in Africa PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA Burke, M. B., Miguel, E., Satyanath, S., Dykema, J. A., Lobell, D. B. 2009; 106 (49): 20670-20674

    Abstract

    Armed conflict within nations has had disastrous humanitarian consequences throughout much of the world. Here we undertake the first comprehensive examination of the potential impact of global climate change on armed conflict in sub-Saharan Africa. We find strong historical linkages between civil war and temperature in Africa, with warmer years leading to significant increases in the likelihood of war. When combined with climate model projections of future temperature trends, this historical response to temperature suggests a roughly 54% increase in armed conflict incidence by 2030, or an additional 393,000 battle deaths if future wars are as deadly as recent wars. Our results suggest an urgent need to reform African governments' and foreign aid donors' policies to deal with rising temperatures.

    View details for DOI 10.1073/pnas.0907998106

    View details for Web of Science ID 000272553000024

    View details for PubMedID 19934048

    View details for PubMedCentralID PMC2781059

  • Shifts in African crop climates by 2050, and the implications for crop improvement and genetic resources conservation GLOBAL ENVIRONMENTAL CHANGE-HUMAN AND POLICY DIMENSIONS Burke, M. B., Lobell, D. B., Guarino, L. 2009; 19 (3): 317-325
  • A Global Model Tracking Water, Nitrogen, and Land Inputs and Virtual Transfers from Industrialized Meat Production and Trade ENVIRONMENTAL MODELING & ASSESSMENT Burke, M., Oleson, K., McCullough, E., Gaskell, J. 2009; 14 (2): 179-193
  • Why are agricultural impacts of climate change so uncertain? The importance of temperature relative to precipitation ENVIRONMENTAL RESEARCH LETTERS Lobell, D. B., Burke, M. B. 2008; 3 (3)
  • Prioritizing climate change adaptation needs for food security in 2030 SCIENCE Lobell, D. B., Burke, M. B., Tebaldi, C., Mastrandrea, M. D., Falcon, W. P., Naylor, R. L. 2008; 319 (5863): 607-610

    Abstract

    Investments aimed at improving agricultural adaptation to climate change inevitably favor some crops and regions over others. An analysis of climate risks for crops in 12 food-insecure regions was conducted to identify adaptation priorities, based on statistical crop models and climate projections for 2030 from 20 general circulation models. Results indicate South Asia and Southern Africa as two regions that, without sufficient adaptation measures, will likely suffer negative impacts on several crops that are important to large food-insecure human populations. We also find that uncertainties vary widely by crop, and therefore priorities will depend on the risk attitudes of investment institutions.

    View details for DOI 10.1126/science.1152339

    View details for Web of Science ID 000252772000037

    View details for PubMedID 18239122

  • International trade in meat: The tip of the pork chop AMBIO Galloway, J. N., Burke, M., Bradford, G. E., Naylor, R., Falcon, W., Chapagain, A. K., Gaskell, J. C., McCullough, E., Mooney, H. A., Oleson, K. L., Steinfeld, H., Wassenaar, T., Smil, V. 2007; 36 (8): 622-629

    Abstract

    This paper provides an original account of global land, water, and nitrogen use in support of industrialized livestock production and trade, with emphasis on two of the fastest-growing sectors, pork and poultry. Our analysis focuses on trade in feed and animal products, using a new model that calculates the amount of "virtual" nitrogen, water, and land used in production but not embedded in the product. We show how key meat-importing countries, such as Japan, benefit from "virtual" trade in land, water, and nitrogen, and how key meat-exporting countries, such as Brazil, provide these resources without accounting for their true environmental cost. Results show that Japan's pig and chicken meat imports embody the virtual equivalent of 50% of Japan's total arable land, and half of Japan's virtual nitrogen total is lost in the US. Trade links with China are responsible for 15% of the virtual nitrogen left behind in Brazil due to feed and meat exports, and 20% of Brazil's area is used to grow soybean exports. The complexity of trade in meat, feed, water, and nitrogen is illustrated by the dual roles of the US and The Netherlands as both importers and exporters of meat. Mitigation of environmental damage from industrialized livestock production and trade depends on a combination of direct-pricing strategies, regulatory approaches, and use of best management practices. Our analysis indicates that increased water- and nitrogen-use efficiency and land conservation resulting from these measures could significantly reduce resource costs.

    View details for Web of Science ID 000251979900002

    View details for PubMedID 18240675

  • The ripple effect: Biofuels, food security, and the environment ENVIRONMENT Naylor, R. L., Liska, A. J., Burke, M. B., Falcon, W. P., Gaskell, J. C., Rozelle, S. D., Cassman, K. G. 2007; 49 (9): 30-43
  • Assessing risks of climate variability and climate change for Indonesian rice agriculture PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA Naylor, R. L., Battisti, D. S., Vimont, D. J., Falcon, W. P., Burke, M. B. 2007; 104 (19): 7752-7757

    Abstract

    El Niño events typically lead to delayed rainfall and decreased rice planting in Indonesia's main rice-growing regions, thus prolonging the hungry season and increasing the risk of annual rice deficits. Here we use a risk assessment framework to examine the potential impact of El Niño events and natural variability on rice agriculture in 2050 under conditions of climate change, with a focus on two main rice-producing areas: Java and Bali. We select a 30-day delay in monsoon onset as a threshold beyond which significant impact on the country's rice economy is likely to occur. To project the future probability of monsoon delay and changes in the annual cycle of rainfall, we use output from the Intergovernmental Panel on Climate Change AR4 suite of climate models, forced by increasing greenhouse gases, and scale it to the regional level by using empirical downscaling models. Our results reveal a marked increase in the probability of a 30-day delay in monsoon onset in 2050, as a result of changes in the mean climate, from 9-18% today (depending on the region) to 30-40% at the upper tail of the distribution. Predictions of the annual cycle of precipitation suggest an increase in precipitation later in the crop year (April-June) of approximately 10% but a substantial decrease (up to 75% at the tail) in precipitation later in the dry season (July-September). These results indicate a need for adaptation strategies in Indonesian rice agriculture, including increased investments in water storage, drought-tolerant crops, crop diversification, and early warning systems.

    View details for DOI 10.1073/pnas.0701825104

    View details for Web of Science ID 000246461500007

    View details for PubMedID 17483453

    View details for PubMedCentralID PMC1876519