scholarly journals Executive Editor comment on "Development of the city-scale chemistry transport model CityChem-EPISODE and its application to the city of Hamburg Matthias Karl"

2018 ◽  
Author(s):  
Astrid Kerkweg
Keyword(s):  
Transport Model ◽  
Chemistry Transport Model ◽  
Editor Comment ◽  
Executive Editor ◽  
The City

scholarly journals Simulation of Mexico City plumes during the MIRAGE-Mex field campaign using the WRF-Chem model

2009 ◽  
Vol 9 (14) ◽  
pp. 4621-4638 ◽  
Author(s):  
X. Tie ◽  
S. Madronich ◽  
G. Li ◽  
Z. Ying ◽  
A. Weinheimer ◽  
...  
Keyword(s):  
Mexico City ◽  
Production Efficiency ◽  
Transport Model ◽  
Major Objective ◽  
Chemistry Transport Model ◽  
Field Campaign ◽  
Mixing Ratios ◽  
The City ◽  
City Plume

Abstract. The quantification of tropospheric O3 production in the downwind of the Mexico City plume is a major objective of the MIRAGE-Mex field campaign. We used a regional chemistry-transport model (WRF-Chem) to predict the distribution of O3 and its precursors in Mexico City and the surrounding region during March 2006, and compared the model with in-situ aircraft measurements of O3, CO, VOCs, NOx, and NOy concentrations. The comparison shows that the model is capable of capturing the timing and location of the measured city plumes, and the calculated variability along the flights is generally consistent with the measured results, showing a rapid increase in O3 and its precursors when city plumes are detected. However, there are some notable differences between the calculated and measured values, suggesting that, during transport from the surface of the city to the outflow plume, ozone mixing ratios are underestimated by about 0–25% during different flights. The calculated O3-NOx, O3-CO, and O3-NOz correlations generally agree with the measured values, and the analyses of these correlations suggest that photochemical O3 production continues in the plume downwind of the city (aged plume), adding to the O3 already produced in the city and exported with the plume. The model is also used to quantify the contributions to OH reactivity from various compounds in the aged plume. This analysis suggests that oxygenated organics (OVOCs) have the highest OH reactivity and play important roles for the O3 production in the aging plume. Furthermore, O3 production per NOx molecule consumed (O3 production efficiency) is more efficient in the aged plume than in the young plume near the city. The major contributor to the high O3 production efficiency in the aged plume is the reaction RO2+NO. By contrast, the reaction of HO2+NO is rather uniformly distributed in the plume.

scholarly journals Simulation of Mexico City plumes during the MIRAGE-Mex field campaign using the WRF-Chem model

2009 ◽  
Vol 9 (2) ◽  
pp. 9221-9266 ◽  
Author(s):  
X. Tie ◽  
S. Madronich ◽  
G. Li ◽  
Z. Ying ◽  
A. Weinheimer ◽  
...  
Keyword(s):  
Mexico City ◽  
Production Efficiency ◽  
Transport Model ◽  
Major Objective ◽  
Chemistry Transport Model ◽  
Aircraft Measurement ◽  
Field Campaign ◽  
Pollution Levels ◽  
The City

Abstract. The quantification of tropospheric O3 production in the Mexico City outflow is a major objective of the MIRAGE-Mex field campaign. We used a regional chemistry-transport model (WRF-Chem) to predict the distribution of O3 and its precursors in Mexico City and the surrounding region during March 2006, and compared with in-situ aircraft measurement of O3, CO, VOCs, NOx, and NOy concentrations. The comparison shows that the model is capable of capturing the timing/location of the measured city plumes, and the calculated variability along the flights is generally consistent with the measured results, showing a rapid enhancement of O3 and its precursors when city plumes are detected. However, there are some notable differences between the calculated and measured values, suggesting that, during transport from the surface of the city to the outflow plume, pollution levels are underestimated by about 0–25% during different flights. The calculated O3-NOx, O3-CO, and O3-NOz correlations generally agree with the measured values, and the analysis of these correlations suggest that photochemical O3 production continues in the plume downwind of the city (aged plume), adding to the O3 already produced in the city and exported with the plume. The model is also used to quantify the contributions to OH reactivity from various compounds in the aged plume. This analysis suggests that oxygenated organics (OVOCs) have the highest OH reactivity and play important roles for the O3 production in the aging plume. Furthermore, O3 production per NOx molecule consumed (O3 production efficiency) is more efficient in the aged plume than in the young plume near the city. The major contributor to the high O3 production efficiency in the aged plume is the reaction RO2+NO. By contrast, the reaction of HO2+NO is rather uniformly distributed in the plume.

scholarly journals Estimating the Exposure Levels of Quercus Pollen: A Case Study in the Greater Area of Thessaloniki, Greece

2021 ◽  
Vol 8 (1) ◽  
pp. 15
Author(s):  
Serafim Kontos ◽  
Dafni Parliari ◽  
Sofia Papadogiannaki ◽  
Dimitrios Melas
Keyword(s):  
Transport Model ◽  
Chemistry Transport Model ◽  
Meteorological Model ◽  
Area Of Interest ◽  
Pollen Concentrations ◽  
Natural Emissions ◽  
Exposure Levels ◽  
Overall Performance ◽  
The City

In this study the exposure levels from Quercus pollen in the greater area of Thessaloniki are estimated. The estimation is implemented with a modeling system, comprising the meteorological model WRF, the Natural Emissions Model (NEMO) for the calculation of the Quercus pollen emissions and the chemistry-transport model CAMx for the advection and the deposition of the pollen particles. The period of 2016 with the highest potential is selected, based on the available measurements for the area of interest. The modeling system is evaluated with meteorological and pollen measurements, as well on the expected exposure levels, indicating a satisfactory overall performance. The modeling system is finally utilized for the estimation of exposure levels in the greater area of Thessaloniki, showing that the city of is not going to experience significant number of days with high Quercus pollen concentrations, although other, smaller cities and towns might be affected.

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