Showing papers by "Deborah Balk published in 2022"

Frameworks to envision equitable urban futures in a changing climate: A multi-level, multidisciplinary case study of New York City

Abstract: Cities are at the forefront of climate change action and planning for futures that are concomitantly more resilient and equitable, making local goals imperative for global sustainability. Under the multiple challenges of changing climatic, ecological and socio-economic conditions, cities need the means to meet these goals. We know cities are and will continue to be points of concentrated and diverse populations, socioeconomic vulnerability, amplified exposure, transformed ecosystems and are responsible for the bulk of the world’s greenhouse gas emissions. Yet, much is also unknown and intrinsically uncertain about urban futures: there is a range of potential plausible futures which have differing implications for both potential mitigation and adaptation actions. To better assess these plausible futures, the “global change” research community developed a framework including scenarios that are applicable for global and regional policy, entitled the Shared Socio-economic Pathways (SSPs) and scenarios exploring future emissions that will drive climate change, entitled Representative Concentration Pathways (RCPs). Importantly, this global scale framework does not include specific city-level perspectives or data at the spatial scales necessary to address questions of local relevance. While the SSPs address many of the key population and socioeconomic drivers of climate change, they do not address important concerns that are particularly relevant to cities, such as racial justice, ecosystem change or migration. Nevertheless, city-level impacts will evolve, in part, as a function of the global scale change characterized by the SSPs, and in part based on demographic and social processes already underway. As such, applying a modification of this framework to cities has the potential to help limit local climate impacts, and create a more resilient, equitable city. To address these needs and respond to city and regional stakeholders, we propose a framework for science-based narratives and quantitative projections for cities and metropolitan areas, such as Greater New York City. In this paper, we review a wide-range of existing approaches to generate estimates of future populations and identify their vulnerabilities to climate-change hazards, ranging from subnational population projections or the spatially-explicit allocation of populations linked to SSPs for the US and selected cities, city-specific population forecasting without climate considerations, and participatory approaches to future scenario development and fine-scale, within-city land use change models. By showcasing the strengths and limitations of various approaches and modeling efforts, their spatial and temporal scales, and thematic breadth, we propose a novel framework that leverages state-of-the art quantitative approaches and couples it with stakeholder engagement that can help cities plan equitably under uncertainty.

The importance of reclassification to understanding urban growth: A demographic decomposition of the United States, 1990–2010

Abstract: An improved understanding of reclassification as a sociodemographic component of urban growth is important for urban planning and sustainable development. However, empirical assessments of the effect of reclassification on urban population dynamics are lacking, especially in countries in the later stage of the urban transition. Using recently available data on spatial reclassification of rural and urban land areas and population, and adopting multiregional demographic methods, we explicitly examine the effects of reclassification, natural growth and rural – urban migration on urban growth in the United States for the intercensal periods of 1990 – 2000 and 2000 – 2010. Results suggest that reclassification played a significant role in U.S. urban population change but its magnitude depends on assumptions about the timing of reclassification. The net effect of reclassification on urban change is the largest when reclassification is assumed to occur at the end, and the smallest when assumed to occur at the beginning, of the decennial census periods. While the impact of natural growth on U.S. urban population change is relatively stable, there is significant uncertainty in the effects of reclassification and rural – urban migration. Additionally, international migration is a key source of urban growth in the United States. We find that the places reclassified from rural to urban or from urban to rural experienced the largest changes in population sizes and age composition.

Built environment as a risk factor for adult overweight and obesity: Evidence from a longitudinal geospatial analysis in Indonesia

Abstract: Indonesia has nearly doubled its urban population in the past three decades. In this period, the prevalence of overweight and obesity in Indonesia has also nearly doubled. We examined 1993–2014 panel data from the Indonesian Family Life Survey (IFLS) to determine the extent to which the increase in one’s built environment contributed to a corresponding increase in adult overweight and obesity during this period. We estimated longitudinal regression models for body mass index (BMI) and being overweight or obese using novel matched geospatial measures of built-up land area. Living in a more built-up area was associated with greater BMI and risk of being overweight or obese. The contribution of the built environment was estimated to be small but statistically significant even after accounting for individuals’ initial BMI. We discuss the findings considering the evidence on nutritional and technological transitions affecting food consumption patterns and physical activity levels in urban and rural areas.

People and infrastructure: multi-scale assessment of coastal and fluvial flood exposure in India

Abstract: India is one of the world’s most flood-prone countries, with present-day risks likely to be exacerbated by climate change in the coming decades. The type of risk varies by location, with the lives, homes, and livelihoods of residents of India’s coastal megacities threatened by coastal floods and storm surges while village-dwellers residing in rural flood plains may additionally lose both crops and livestock. Schools and health facilities throughout the country are also at risk. This multi-scale study employs several datasets, from multiple domains, to generate high-resolution estimates of potential exposure to fluvial and coastal floods for (1) urban and rural populations, (2) health facilities, and (3) educational facilities. Our results, presented at the state level, suggest high exposure to fluvial flooding with about 184 million or more than 1:7 of India’s population at risk. This proportion is somewhat higher for rural dwellers (15.8%) compared with urban residents (14.2%). Urban residents, however, are much more likely to be affected by coastal floods, likely due to the high population densities of India’s coastal megacities. In total, around 19,218 (15%) of health and 34,519 (18%) of educational facilities are exposed to either coastal or fluvial flood risks. A spatially detailed, locally refined, comprehensive flood risk assessment such as this is critical to inform and target public policy and guide disaster risk reduction plans. By improving infrastructure, increasing awareness, and developing proactive, targeted, and inclusive flood plans, communities can build resilience.