arXiv subjects

Arianna Salazar-Miranda

Publications and source records attributed to Arianna Salazar-Miranda.

4 recordsLinked to original sources

arXiv2026

What Do City Codes Say About Climate Risk?

Climate change is intensifying natural hazards, and preparing cities for them falls primarily to local governments. Yet what municipal codes say about hazards, and whether their requirements match each city's risk profile, has not been measured. I analyze 3.6 million sentences from 204 U.S. cities' municipal codes and compare each city's hazard text to its actual risk from FEMA's National Risk Index. I document four patterns. First, a small share of code text consists of provisions relevant for natural hazards (1.5%), and codes in high-risk cities contain marginally more. Second, hazard coverage is highly concentrated on flooding (61% of hazard-relevant text), even though flooding accounts for only 9% of the average city's risk. Third, city codes emphasize emergency response over prevention. Emergency management is the largest regulatory category, and land use is the smallest. Fourth, codes track the types of risks relevant to each location, but only loosely. The median city would need to reallocate 70% of its regulatory text to match its risk profile. The results suggest that U.S. city codes do not include regulation for most of the hazards cities face.

physics.soc-ph↗

arXiv2025

The Influence of Neighborhood Design on the Sustainability of US Suburbs

The growth of suburbs in the US has led to significant sustainability challenges; yet, it remains unclear whether these challenges stem from the remoteness of suburbs from city centers or the specific designs used to develop them. This paper examines how Garden City Design (GCD) -- one of the most influential suburban design paradigms since the early 20th century -- impacts the social and environmental outcomes of neighborhoods. I first introduce a composite measure of GCD, derived from street layouts and block configurations, to quantify its nationwide adoption. I use this measure combined with mobility and emissions data to estimate the impact of GCD on neighborhood outcomes using complementary identification strategies, including ordinary least squares (OLS), matching estimators, and an instrumental variables (IV) approach that exploits historical variation in GCD adoption. Results show that GCD leads to worse sustainability outcomes, including increased greenhouse gas emissions, greater social isolation, and higher sedentary behavior. The prevalence of GCD accounts for 27-38% of the adverse effects associated with suburbanization, underscoring the crucial role that neighborhood design plays in shaping urban sustainability.

physics.soc-ph↗

arXiv2025

Zoning in American Cities: Are Reforms Making a Difference? An AI-based Analysis

Cities are at the forefront of addressing global sustainability challenges, particularly those exacerbated by climate change. Traditional zoning codes, which often segregate land uses, have been linked to increased vehicular dependence, urban sprawl, and social disconnection, undermining broader social and environmental sustainability objectives. This study investigates the adoption and impact of form-based codes (FBCs), which aim to promote sustainable, compact, and mixed-use urban forms as a solution to these issues. Using Natural Language Processing (NLP) techniques, we analyzed zoning documents from over 2000 U.S. census-designated places to identify linguistic patterns indicative of FBC principles. Our findings reveal widespread adoption of FBCs across the country, with notable variations within regions. FBCs are associated with higher floor-to-area ratios, narrower and more consistent street setbacks, and smaller plots. We also find that places with FBCs have improved walkability, shorter commutes, and a higher share of multi-family housing. Our findings highlight the utility of NLP for evaluating zoning codes and underscore the potential benefits of form-based zoning reforms for enhancing urban sustainability.

cs.CY↗

arXiv2022

The 15-Minute City Quantified Using Mobility Data

Americans travel 7 to 9 miles on average for shopping and recreational activities, which is far longer than the 15-minute (walking) city advocated by ecologically-oriented urban planners. This paper provides a comprehensive analysis of local trip behavior in US cities using GPS data on individual trips from 40 million mobile devices. We define local usage as the share of trips made within 15-minutes walking distance from home, and find that the median US city resident makes only 12% of their daily trips within such a short distance. We find that differences in access to local services can explain eighty percent of the variation in 15-minute usage across metropolitan areas and 74 percent of the variation in usage within metropolitan areas. Differences in historic zoning permissiveness within New York suggest a causal link between access and usage, and that less restrictive zoning rules, such as permitting more mixed-use development, would lead to shorter travel times. Finally, we document a strong correlation between local usage and experienced segregation for poorer, but not richer, urbanites, which suggests that 15-minute cities may also exacerbate the social isolation of marginalized communities.

physics.soc-ph↗