Dataset Information

Assessing Temporal and Spatial Patterns of Observed and Predicted Ozone in Multiple Urban Areas.

ABSTRACT:

Background

Ambient monitoring data show spatial gradients in ozone (O3) across urban areas. Nitrogen oxide (NOx) emissions reductions will likely alter these gradients. Epidemiological studies often use exposure surrogates that may not fully account for the impacts of spatially and temporally changing concentrations on population exposure.

Objectives

We examined the impact of large NOx decreases on spatial and temporal O3 patterns and the implications on exposure.

Methods

We used a photochemical model to estimate O3 response to large NOx reductions. We derived time series of 2006-2008 O3 concentrations consistent with 50% and 75% NOx emissions reduction scenarios in three urban areas (Atlanta, Philadelphia, and Chicago) at each monitor location and spatially interpolated O3 to census-tract centroids.

Results

We predicted that low O3 concentrations would increase and high O3 concentrations would decrease in response to NOx reductions within an urban area. O3 increases occurred across larger areas for the seasonal mean metric than for the regulatory metric (annual 4th highest daily 8-hr maximum) and were located only in urban core areas. O3 always decreased outside the urban core (e.g., at locations of maximum local ozone concentration) for both metrics and decreased within the urban core in some instances. NOx reductions led to more uniform spatial gradients and diurnal and seasonal patterns and caused seasonal peaks in midrange O3 concentrations to shift from midsummer to earlier in the year.

Conclusions

These changes have implications for how O3 exposure may change in response to NOx reductions and are informative for the design of future epidemiology studies and risk assessments.

Citation

Simon H, Wells B, Baker KR, Hubbell B. 2016. Assessing temporal and spatial patterns of observed and predicted ozone in multiple urban areas. Environ Health Perspect 124:1443-1452; http://dx.doi.org/10.1289/EHP190.

SUBMITTER: Simon H

PROVIDER: S-EPMC5010397 | biostudies-literature | 2016 Sep

REPOSITORIES: biostudies-literature

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Publications

Assessing Temporal and Spatial Patterns of Observed and Predicted Ozone in Multiple Urban Areas.

Simon Heather H Wells Benjamin B Baker Kirk R KR Hubbell Bryan B

Environmental health perspectives 20160506 9

<h4>Background</h4>Ambient monitoring data show spatial gradients in ozone (O3) across urban areas. Nitrogen oxide (NOx) emissions reductions will likely alter these gradients. Epidemiological studies often use exposure surrogates that may not fully account for the impacts of spatially and temporally changing concentrations on population exposure.<h4>Objectives</h4>We examined the impact of large NOx decreases on spatial and temporal O3 patterns and the implications on exposure.<h4>Methods</h4>W ...[more]

PMID: 27153213

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Dataset Information

Assessing Temporal and Spatial Patterns of Observed and Predicted Ozone in Multiple Urban Areas.

Background

Objectives

Methods

Results

Conclusions

Citation

Publications

Assessing Temporal and Spatial Patterns of Observed and Predicted Ozone in Multiple Urban Areas.

Similar Datasets

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