Urban core-downwind differences and relationships related to ozone production in a major urban area in Texas

Abstract. The sensitivity of ozone production to precursor emissions was investigated under five different meteorological conditions in the Mexico City Metropolitan Area (MCMA) during the MCMA-2006/MILAGRO field campaign using the gridded photochemical model CAMx driven by observation-nudged WRF meteorology. Precursor emissions were constrained by the comprehensive data from the field campaign and the routine ambient air quality monitoring network. Simulated plume mixing and transport were examined by comparing with measurements from the G-1 aircraft during the campaign. The observed concentrations of ozone precursors and ozone were well reproduced by the model. The effects of reducing precursor emissions on urban ozone production were performed for three representative emission control strategies. A 50% reduction in VOC emissions led to 7 to 22 ppb decrease in daily maximum ozone concentrations, while a 50% reduction in NOx emissions leads to 4 to 21 ppb increase, and 50% reductions in both NOx and VOC emission decrease the daily maximum ozone concentrations up to 10 ppb. These results along with a chemical indicator analysis using the chemical production ratios of H2O2 to HNO3 demonstrate that the MCMA urban core region is VOC-limited for all meteorological episodes, which is consistent with the results from MCMA-2003 field campaign; however the degree of the VOC-sensitivity is higher in the MCMA-2006 due to lower VOC/NOx emission ratio and VOC reactivity. Ozone formation in the surrounding mountain/rural area is mostly NOx-limited, but can be VOC-limited, and the range of the NOx-limited or VOC-limited areas depends on meteorology.

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Ozone response to emission changes: a modeling study during the MCMA-2006/MILAGRO Campaign

Atmospheric Chemistry and Physics ◽

10.5194/acp-10-3827-2010 ◽

2010 ◽

Vol 10 (8) ◽

pp. 3827-3846 ◽

Cited By ~ 62

Author(s):

J. Song ◽

W. Lei ◽

N. Bei ◽

M. Zavala ◽

B. de Foy ◽

...

Keyword(s):

Monitoring Network ◽

Ambient Air ◽

Ozone Production ◽

Daily Maximum ◽

Nox Emissions ◽

Chemical Production ◽

Field Campaign ◽

Ozone Concentrations ◽

Urban Core ◽

Emission Changes

Abstract. The sensitivity of ozone production to precursor emissions was investigated under five different meteorological conditions in the Mexico City Metropolitan Area (MCMA) during the MCMA-2006/MILAGRO field campaign using the gridded photochemical model CAMx driven by observation-nudged WRF meteorology. Precursor emissions were constrained by the comprehensive data from the field campaign and the routine ambient air quality monitoring network. Simulated plume mixing and transport were examined by comparing with measurements from the G-1 aircraft during the campaign. The observed concentrations of ozone precursors and ozone were reasonably well reproduced by the model. The effects of reducing precursor emissions on urban ozone production were performed for three representative emission control scenarios. A 50% reduction in VOC emissions led to 7 to 22 ppb decrease in daily maximum ozone concentrations, while a 50% reduction in NOx emissions leads to 4 to 21 ppb increase, and 50% reductions in both NOx and VOC emission decrease the daily maximum ozone concentrations up to 10 ppb. These results along with a chemical indicator analysis using the chemical production ratios of H2O2 to HNO3 demonstrate that the MCMA urban core region is VOC-limited for all meteorological episodes, which is consistent with the results from MCMA-2003 field campaign; however the degree of the VOC-sensitivity is higher during MCMA-2006 due to lower VOCs, lower VOC reactivity and moderately higher NOx emissions. Ozone formation in the surrounding mountain/rural area is mostly NOx-limited, but can be VOC-limited, and the range of the NOx-limited or VOC-limited areas depends on meteorology.

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Megacity impacts on regional ozone formation: observations and WRF-Chem modeling for the MIRAGE-Shanghai field campaign

Atmospheric Chemistry and Physics ◽

10.5194/acp-13-5655-2013 ◽

2013 ◽

Vol 13 (11) ◽

pp. 5655-5669 ◽

Cited By ~ 87

Author(s):

X. Tie ◽

F. Geng ◽

A. Guenther ◽

J. Cao ◽

J. Greenberg ◽

...

Keyword(s):

Urban Area ◽

Air Pollutants ◽

Regional Scale ◽

Threshold Value ◽

Sensitivity Study ◽

Ozone Production ◽

Ozone Formation ◽

Limited Condition ◽

Ozone Concentrations ◽

Regional Area

Abstract. The MIRAGE-Shanghai experiment was designed to characterize the factors controlling regional air pollution near a Chinese megacity (Shanghai) and was conducted during September 2009. This paper provides information on the measurements conducted for this study. In order to have some deep analysis of the measurements, a regional chemical/dynamical model (version 3 of Weather Research and Forecasting Chemical model – WRF-Chemv3) is applied for this study. The model results are intensively compared with the measurements to evaluate the model capability for calculating air pollutants in the Shanghai region, especially the chemical species related to ozone formation. The results show that the model is able to calculate the general distributions (the level and the variability) of air pollutants in the Shanghai region, and the differences between the model calculation and the measurement are mostly smaller than 30%, except the calculations of HONO (nitrous acid) at PD (Pudong) and CO (carbon monoxide) at DT (Dongtan). The main scientific focus is the study of ozone chemical formation not only in the urban area, but also on a regional scale of the surrounding area of Shanghai. The results show that during the experiment period, the ozone photochemical formation was strongly under the VOC (volatile organic compound)-limited condition in the urban area of Shanghai. Moreover, the VOC-limited condition occurred not only in the city, but also in the larger regional area. There was a continuous enhancement of ozone concentrations in the downwind of the megacity of Shanghai, resulting in a significant enhancement of ozone concentrations in a very large regional area in the surrounding region of Shanghai. The sensitivity study of the model suggests that there is a threshold value for switching from VOC-limited condition to NOx (nitric oxide and nitrogen dioxide)-limited condition. The threshold value is strongly dependent on the emission ratio of NOx / VOCs. When the ratio is about 0.4, the Shanghai region is under a strong VOC-limited condition over the regional scale. In contrast, when the ratio is reduced to about 0.1, the Shanghai region is under a strong NOx-limited condition. The estimated threshold value (on the regional scale) for switching from VOC-limited to NOx-limited condition ranges from 0.1 to 0.2. This result has important implications for ozone production in this region and will facilitate the development of effective O3 control strategies in the Shanghai region.

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Megacity impacts on regional ozone formation: observations and WRF-Chem modeling for the MIRAGE-Shanghai field campaign

Atmospheric Chemistry and Physics Discussions ◽

10.5194/acpd-13-1673-2013 ◽

2013 ◽

Vol 13 (1) ◽

pp. 1673-1716

Author(s):

X. Tie ◽

F. Geng ◽

A. Guenther ◽

J. Cao ◽

J. Greenberg ◽

...

Keyword(s):

Urban Area ◽

Air Pollutants ◽

Regional Scale ◽

Threshold Value ◽

Sensitivity Study ◽

Ozone Production ◽

Ozone Formation ◽

Limited Condition ◽

Ozone Concentrations ◽

Regional Area

Abstract. The MIRAGE-Shanghai experiment was designed to characterize the factors controlling regional air pollution near a Chinese Megacity (Shanghai) and was conducted during September 2009. This paper provides an overview of the measurements conducted for this study. In addition to the measurements, a regional chemical/dynamical model (version 3 of Weather Research and Forecasting Chemical model – WRF-Chemv3) is applied for this study. The model results are intensively compared with the measurements to evaluate the model capability for calculating air pollutants in the Shanghai region, especially the chemical species related to ozone formation. The results show that the model is able to calculate the general distributions (the level and the variability) of air pollutants in the Shanghai region, and the difference between the model calculation and the measurement are mostly smaller than 30%, except the calculations of HONO at PD (Pudong) and CO at DT (Dongtan). The main scientific focus is the study of ozone chemical formation not only in the urban area, but also on a regional scale of the surrounding area of Shanghai. The results show that during the experiment period, the ozone photochemical formation was strongly under the VOC-limited condition in the urban area of Shanghai. Moreover, the VOC-limited condition occurred not only in the city, but also in the larger regional area. There was a continuous enhancement of ozone concentrations in the downwind of the megacity of Shanghai, resulting in a significant enhancement of ozone concentrations in a very large regional area in the surrounding region of Shanghai. The sensitivity study of the model suggests that there is a threshold value for switching from VOC-limited condition to NOx-limited condition. The threshold value is strongly dependent on the emission ratio of NOx/VOCs. When the ratio is about 0.4, the Shanghai region is under a strong VOC-limited condition over the regional scale. In contrast, when the ratio is reduced to about 0.1, the Shanghai region is under a strong NOx-limited condition. The estimated threshold value (on the regional scale) for switching from VOC-limited to NOx-limited condition ranges from 0.1 to 0.2. This result has important implications for ozone production in this region and will facilitate the development of effective O3 control strategies in the Shanghai region.

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The impact of wildfire smoke on ozone production in an urban area: insights from field observations and photochemical box modeling

Atmospheric Environment ◽

10.1016/j.atmosenv.2021.118764 ◽

2021 ◽

pp. 118764

Author(s):

Matthew Ninneman ◽

Daniel A. Jaffe

Keyword(s):

Urban Area ◽

Ozone Production ◽

Field Observations ◽

Wildfire Smoke ◽

The Impact

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Ozone production efficiency in an urban area

Journal of Geophysical Research Atmospheres ◽

10.1029/2002jd002529 ◽

2002 ◽

Vol 107 (D23) ◽

pp. ACH 23-1-ACH 23-12 ◽

Cited By ~ 71

Author(s):

Lawrence I. Kleinman ◽

Peter H. Daum ◽

Yin-Nan Lee ◽

Linda J. Nunnermacker ◽

Stephen R. Springston ◽

...

Keyword(s):

Urban Area ◽

Production Efficiency ◽

Ozone Production

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Transport Accessibility in a Suburban Zone and Its Influence on the Local Real Estate Market: A Case Study of the Olsztyn Functional Urban Area (Poland)

Land ◽

10.3390/land10050465 ◽

2021 ◽

Vol 10 (5) ◽

pp. 465

Author(s):

Agnieszka Szczepańska

Keyword(s):

Real Estate ◽

Urban Area ◽

Population Distribution ◽

Rank Correlation ◽

Real Estate Market ◽

Property Market ◽

Spearman’S Rank Correlation ◽

Urban Core ◽

Spearman’S Rank Correlation Coefficient ◽

Commuting Time

The development of real estate markets in the vicinity of cities is linked with suburbanization processes. The migration of the population to suburban areas contributes to the growth of the residential property market (houses, apartments and construction plots). To minimize commuting costs, property buyers opt for locations that are situated close to the urban core. This article analyzes construction plots on the local real estate market in the Olsztyn Functional Urban Area, in terms of their temporal accessibility and demographic changes. Spatial variations in population distribution were analyzed with the use of the Gini index and geostatistical interpolation techniques. Spearman’s rank correlation coefficient was calculated to determine the relationships between the analyzed variables. The study revealed differences in the spatial distribution of the population and real estate transactions as well as strong correlations between average transaction price, number of transactions, commuting time and population. The highest number of transactions were observed in cadastral districts situated in the direct vicinity of Olsztyn’s administrative boundaries and the major transportation routes due to their high temporal accessibility.

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