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To estimate the pollution impact of seven sample airports in California on the surrounding schools, routine high-quality observations of 1-min average wind direction and speed at the airports were used to calculate the time each school within a 10-km radius was downwind of each airport. We demonstrate 0.87 correlation between pollution levels and downwind time at Los Angeles International Airport (LAX). Depending on the airport size, between 10 and 15 years of data was collected and downwind times calculated for the school hours throughout the school-months of August to June. By comparing this data with the 2015–2016 student enrollment size and demographics of the neighboring schools, we have demonstrated that an estimated 65,409 (8.7%) students spend 1–6 h per day at school throughout the academic year with exposure to airport-related air pollution. However, a higher proportion of economically disadvantaged students (10.6%) experience aforementioned levels of exposure. The level of exposure does not appear to be affected by the proposed 1-h delay in the school starting time that is intended to reduce student fatigue. • Algorithms based on local back-trajectories are practical and flexible tools to estimate exposure to airport emissions. • Downwind time calculations have an overall 0.87 correlation with the levels of air pollutants at LAX. • An estimated 65,409 (8.7%) students in schools surrounding airports get significant exposure to pollutant. • Low socioeconomic students comprise a disproportionately large segment (10.6%) of the exposed students. [ABSTRACT FROM AUTHOR]

This article analyzes the impact of changing housing and neighborhood characteristics on the accessibility of neighborhood businesses using Long Beach, California, as a case study. Although advocates of smart growth and New Urbanism encourage land use mixing, aggregate-level analysis can be too coarse to pick up on fine-grained aspects of urban streetscapes. This study uses assessor parcel records and a point-based business establishment data set to analyze city-wide patterns of accessibility from individual dwelling units to thirty-one types of neighborhood businesses, including grocery stores, service shops, drug stores, doctor's offices, and banks. Regression results compare parcel-level and neighborhood-level drivers of accessibility between 2006 and 2015 to gauge the aggregated effect of recent economic, demographic, and built environment changes on this aspect of urban spatial structure. Larger homes in older, multiunit buildings and higher income neighborhoods show substantial increases in accessibility to most establishment types, suggesting a trend toward both greater accessibility and larger dwelling units—despite the traditional trade-off between access and space. Although gradual increases in home and business density increased overall accessibility over this period, weaker neighborhood-level results indicate that this trend is less pronounced in high-poverty and non-white areas. [ABSTRACT FROM AUTHOR]

The Los Angeles–Long Beach harbor is the busiest port in the US. Levels of particulate matter (PM) are relatively high in this area, since it is affected by multiple PM sources. A Chemical Mass Balance (CMB) model was applied to speciated chemical measurements of quasi-ultrafine and fine particulate matter from seven different sites. Winter measurements were obtained during a 7-week period between March and May 2007, and summer measurements corresponded to a 6-week period between July and September 2007. Four of the sites were located within the communities of Wilmington and Long Beach, two sites were located at a background area in the harbor of Los Angeles and Long Beach, and one more site was located further downwind, near downtown Los Angeles, representing urban downtown LA, influenced by mostly traffic sources. The samples were analyzed for organic (OC) and elemental (EC) carbon content, organic species, inorganic ions, water soluble and total elements. The sources included in the CMB model were light duty vehicles (LDV), heavy-duty vehicles (HDV), road dust (RD), biomass burning and ship emissions. The model predictions of the LDV and HDV source contributions accounted, on average, for 83% of total fine OC in winter and for 70% in summer, whereas ship emissions’ contribution was lower than 5% of total OC at all sites. In the quasi-ultrafine mode, the vehicular sources accounted for 118% in winter and 103% in summer. Spatial variation of source contributions was not very pronounced with the exception of some specific sites. In terms of total fine PM, vehicular sources together with road dust explain up to 54% of the mass, whereas ship contribution is lower than 5% of total fine PM mass. Our results clearly indicate that, although ship emissions can be significant, PM emissions in the area of the largest US harbor are dominated by vehicular sources. [Copyright &y& Elsevier]

This paper focuses on the process of institutional change at the leading ports of the United States: Los Angeles and Long Beach. In order to do so, it makes use of the structure of provision-approach and the concept of regime politics which allows for a systematic analysis and comparison. Key questions are: how are both ports institutionally structured? How do they evolve in relation to each other? And what is the role of agency in this process? The paper reveals how both ports remain institutionally different in spite of competition. This persistent institutional diversity can be explained by that fact that institutions represent territorially rooted structures of power in which competitive performance will not always be the decisive interest. [ABSTRACT FROM AUTHOR]