At the intersection of physical sciences and policy, our researchers work to find solutions for hunger, environmental degradation, emerging energy markets and more.
Research Spotlight
Economic Policy Challenges Facing California's Next Governor: Electricity Policy Reform
Because Californians are likely to want to continue to lead the energy transition, the relevant policy design question is: How can the state achieve these low-carbon energy goals in a more cost- effective manner?
Climate Change is Increasing the Risk of Extreme Autumn Wildfire Conditions Across California
The climate model analyses presented here suggest that continued climate change will further amplify the number of days with extreme fire weather by the end of this century, though a pathway consistent with the UN Paris commitments would substantially curb that increase.
Sight for Sorghums: Comparisons of Satellite- and Ground-Based Sorghum Yield Estimates in Mali
Leveraging a survey experiment in Mali, this study uses plot-level sorghum yield estimates, based on farmer reporting and crop cutting, to construct and evaluate estimates from three satellite-based sensors.
Natural infrastructure such as parks, forests, street trees, green roofs, and coastal vegetation is central to sustainable urban management. Despite recent progress, it remains challenging for urban decision-makers to incorporate the benefits of natural infrastructure into urban design and planning. Here, we present an approach to support the greening of cities by quantifying and mapping the diverse benefits of natural infrastructure for now and in the future. The approach relies on open-source tools, within the InVEST (Integrated Valuation of Ecosystem Services and Tradeoffs) software, that compute biophysical and socio-economic metrics relevant to a variety of decisions in data-rich or data-scarce contexts. Through three case studies in China, France, and the United States, we show how spatially explicit information about the benefits of nature enhances urban management by improving economic valuation, prioritizing land use change, and promoting inclusive planning and stakeholder dialogue. We discuss limitations of the tools, including modeling uncertainties and a limited suite of output metrics, and propose research directions to mainstream natural infrastructure information in integrated urban management.
Background: Attention deficit hyperactivity disorder (ADHD) is a widely recognized mental health problem in developed countries but remains under-investigated in developing settings. This study examines the prevalence, correlates, and consequences of ADHD symptoms among elementary school students in rural China. Methods: Cross-sectional data were collected from 6,719 students across 120 rural primary schools in China on ADHD symptoms, demographic characteristics, and academic performance in reading and math. ADHD symptoms were evaluated using the caregiver-reported ADHD Rating Scale-IV. Results: The prevalence of ADHD symptoms was 7.5% in our sample. Male students, students in lower grade levels, and students with lower cognitive ability showed a significantly higher prevalence of ADHD symptoms (ORs = 2.56, 2.06, and 1.84, respectively; p<0.05). Left-behind children showed a significantly lower prevalence of ADHD symptoms than did children who were living with their parents (OR = 0.74, p < 0.05). Adjusted regressions show that students with ADHD symptoms scored 0.12 standardized deviations lower in reading (p < 0.05) and 0.19 standardized deviations lower in math (p < 0.01). Limitations: The ADHD Rating Scale-IV is a screening scale rather than a diagnostic test. Caregiver self-report measures also may underestimate ADHD symptoms for our sample. Conclusions: ADHD is a common disorder among rural students in China and appears to be contributing to poor academic outcomes. The higher prevalence of ADHD among students with low cognitive ability also suggests that many rural children in China face multifactorial learning challenges. Taken together, the findings indicate a need for educators and policymakers in rural China to develop programs to reduce risk and support students with ADHD symptoms.
China’s economy has doubled in size every eight years since 1979, making it over 32 times bigger now then it was then and the second largest in the world today.1 Four decades of growth have ushered more than 400 million people in China into the global middle class.2 According to the World Bank, China is currently an upper middle-income country. The country is the only major economy on earth to report growth in 2020 in the wake of the coronavirus pandemic.3 What are the prospects for China to continue its spectacular economic rise and become a high-income country? In this article, we aim to draw attention to an underappreciated factor that we believe may complicate China’s continued economic ascent: hundreds of millions of poorly educated, increasingly underemployed workers hailing from China’s rural hinterland.
Scott Rozelle, Yuqing Zheng, and Chengfang Liu were the guest editors of this special issue on agriculture, the rural economy and China's growth in the 21st century. Scott Rozelle also authored a publication in this issue.
Digital contact tracing has the potential to limit the spread of COVID-19. A contact-tracing smartphone app that has been readily adopted by people in England and Wales has shown efficacy in reducing disease spread.
We use high resolution satellite data on the proportion of buildings in a 250x250 meter cell to study the evolution of human settlement in Ghana over a 40 year period. We find a strong increase in built-up area over time, mostly concentrated in the vicinity of roads, and also directly on the coast. We find strong evidence of agglomeration effects both in the static sense—buildup in one cell predicts buildup in a nearby cell—and in a dynamic sense—buildup in a cell predicts buildup in that cell later on and an increase in buildup in nearby cells. These effects are strongest over a 3 to 15 Km radius, which corresponds to a natural hinterland for a population without mechanized transportation. We find no evidence that human settlements are spaced more or less equally either over the landscape or along roads. This suggests that arable land is not yet fully utilized, allowing rural settlements to be separated by areas of un-farmed land. By fitting a transition matrix to the data, we predict a sharp increase in the proportion of the country that is densely built-up by the middle and the end of the century, but no increase in the proportion of partially built-up locations.
Based on three years of intensive research and analysis of the Nuclear Archives, this new book from the Institute presents a compelling account of Iran’s secret plans to develop nuclear weapons. Frank was the Geospatial Contributing Analyst.
Environmental Research and Public Health,
May 15, 2021
This study examines the prevalence of cognitive delay among infants and toddlers in rural China and its relationship with one of the potential sources of the observed delay: low levels of stimulating parenting practices (SPPs). Data were compiled from five distinct studies, resulting in a pooled sample of 4436 caregivers of 6–29-month-old infants. The sampling sites span five provinces in rural China. According to the data, on average, rates of delay are high—51 percent. The low rates of SPPs among our sample demonstrate that this may be one source of the high prevalence of delays. The results of the multivariate regression analysis reveal that reading books and singing songs are each significantly associated with an increase in infant cognitive score by 1.62 points (p = 0.003) and 2.00 points (p 0.001), respectively. Telling stories to infants, however, is not significantly associated with infant cognitive scores. Our findings indicate that caregivers with different characteristics engage in various levels of stimulating practices and have infants with different rates of delay. Specifically, infants of better-educated mothers who have greater household assets are in families in which the caregivers provide more SPPs and have infants who score higher on the study’s cognitive abilities scales.
Nature underpins human well-being in critical ways, especially in health. Nature provides pollination of nutritious crops, purification of drinking water, protection from floods, and climate security, among other well-studied health benefits. A crucial, yet challenging, research frontier is clarifying how nature promotes physical activity for its many mental and physical health benefits, particularly in densely populated cities with scarce and dwindling access to nature. Here we frame this frontier by conceptually developing a spatial decision-support tool that shows where, how, and for whom urban nature promotes physical activity, to inform urban greening efforts and broader health assessments. We synthesize what is known, present a model framework, and detail the model steps and data needs that can yield generalizable spatial models and an effective tool for assessing the urban nature–physical activity relationship. Current knowledge supports an initial model that can distinguish broad trends and enrich urban planning, spatial policy, and public health decisions. New, iterative research and application will reveal the importance of different types of urban nature, the different subpopulations who will benefit from it, and nature’s potential contribution to creating more equitable, green, livable cities with active inhabitants.
