scholarly journals Evaluation of regional simulation of surface ozone over Southeast Asia using ground-based observation at two existing Global Atmospheric Watch stations

2021 ◽  
Vol 880 (1) ◽  
pp. 012006
Author(s):  
Didin Agustian Permadi ◽  
Nguyen Thi Kim Oanh
Keyword(s):  
Air Quality ◽  
Urban Areas ◽  
Emission Inventory ◽  
Surface Ozone ◽  
Wrf Model ◽  
Ambient Air ◽  
Quality Standard ◽  
Ozone Pollution ◽  
Ozone Precursors ◽  
Remote Sites

Abstract High level of ground level ozone concentrations was found in most of Southeast Asian (SEA) large cities and often exceeded the national ambient air quality standard. Ozone and PM10 are among of the critical air quality parameters that cause the unhealthy air quality index. Effort to mitigate ozone pollution is greatly complicated due to the photochemistry processes therefore photochemical smog modelling has been widely used. Surface ozone simulation in SEA was done using CHIMERE and weather research forecast (WRF) model. Emission inventory of ozone precursors was done for three countries in the domain, i.e. Indonesia, Thailand and Cambodia. Modelling performance evaluation for meteorological parameters and ozone at the SEA big cities was done in another study. This paper focused on the model evaluation conducted at the two remote sites represented by 2 (two) global atmospheric watch (GAW) remote stations of Bukit Kototabang (BKT) and Danum Valley (DNV). Evaluation result showed an overestimation of observed ozone in BKT while a contradictive result was seen in DNV station which was due to the ozone chemistry and inaccurate estimation of emissions (both anthropogenic and biogenic emission). The evaluation conducted at the remote sites was not even better than that conducted previously at the urban areas. Statistically, only mean normalized gross error and unpaired peak accuracy values that satisfy the criteria for surface ozone modelling suggesting major improvement required for ozone precursors emission inventory data.

scholarly journals Spatio-temporal of surface ozone (O3) variations at urban and suburban sites in Sarawak region of Malaysia

2021 ◽  
Vol 880 (1) ◽  
pp. 012004
Author(s):  
H Mahidin ◽  
M T Latif ◽  
A Hamdan ◽  
J Salleh ◽  
D Dominick ◽  
...  
Keyword(s):  
Air Quality ◽  
Surface Ozone ◽  
Ambient Air ◽  
Quality Standard ◽  
Transportation Systems ◽  
Pollutant Emissions ◽  
Daily Maximum ◽  
Spatio Temporal ◽  
Ambient Air Quality Standard ◽  
The Relationship

Abstract Sarawak Region of Malaysia is currently experiencing a high demand for capital needs such as transformation forest to plantations, economic development, and improving transportation systems. Those land cover changes will increase primary pollutant emissions and trigger surface O3 formation. Surface O3 is a secondary pollutant and a significant greenhouse gas contributing to climate change and declining air quality. In this study, variations in surface O3 concentrations at urban and suburban sites in Sarawak were explored using the Malaysian Department of Environment data spanning a two-year cycle (2018-2019). The primary aim of this study is to ascertain the variation of surface O3 concentrations reported at four monitoring stations in Sarawak, namely Kuching (SQ1) (Urban), Sibu (SQ2) (Suburban), Bintulu (SQ3) (Suburban), and Miri (SQ4) (Suburban). The study also analysed the relationship between O3 distribution and nitrogen oxides (NO and NO2). The findings showed that O3 concentrations observed in the region during the study period were lower than the maximum permissible value of 100 ppbv suggested by the Malaysian Ambient Air Quality Standard (2020). SQ4 (Miri) at suburban sites recorded the highest average surface O3 concentrations with an hourly average and daily maximum O3 concentration of 15.7 and 89.5 ppbv, respectively. Temperatures, UV exposure, and wind speed all impact the concentration of surface O3 in Sarawak. In all stations, concentrations of O3 were inversely linked with NO, NO2, and relative humidity (RH). This research will assist the relevant agency in forecast, monitor, and mitigate the level of O3 in the ambient environment, especially in the Sarawak Region.

Smoke incursions into urban areas: simulation of a Georgia prescribed burn

2009 ◽  
Vol 18 (3) ◽  
pp. 336 ◽  
Author(s):  
Yongqiang Liu ◽  
Scott Goodrick ◽  
Gary Achtemeier ◽  
William A. Jackson ◽  
John J. Qu ◽  
...  
Keyword(s):  
Air Quality ◽  
Urban Areas ◽  
Ambient Air ◽  
Quality Standard ◽  
Prescribed Burn ◽  
Modeling Framework ◽  
North West ◽  
Transport Direction ◽  
Smoke Plumes ◽  
Ambient Air Quality Standard

This study investigates smoke incursion into urban areas by examining a prescribed burn in central Georgia, USA, on 28 February 2007. Simulations were conducted with a regional modeling framework to understand transport, dispersion, and structure of smoke plumes, the air quality effects, sensitivity to emissions, and the roles of burn management strategy in mitigating the effects. The results indicate that smoke plumes first went west, but turned north-west at noon owing to a shift in wind direction. The smoke then invaded metropolitan Atlanta during the evening rush hour. The plumes caused severe air quality problems in Atlanta. Some hourly ground PM2.5 (particulate matter not greater than 2.5 μm in diameter) concentrations at three metropolitan Atlanta locations were three to four times as high as the daily (24-h) US National Ambient Air Quality Standard. The simulated shift in the smoke transport direction and the resultant effects on air quality are supported by the satellite and ambient air measurements. Two sensitivity simulations indicate a nearly linear relation between the emission intensities and PM2.5 concentrations. Two other simulations indicate that the impacts on air quality for the residents of Atlanta during the evening commute could have been reduced if the starting time of the burn had been altered.

scholarly journals Feasibility and difficulties of China's new air quality standard compliance: PRD case of PM<sub>2.5</sub> and ozone from 2010 to 2025

2013 ◽  
Vol 13 (23) ◽  
pp. 12013-12027 ◽  
Author(s):  
H. Liu ◽  
X. M. Wang ◽  
J. M. Pang ◽  
K. B. He
Keyword(s):  
Air Quality ◽  
Control Strategies ◽  
Nox Reduction ◽  
Ambient Air ◽  
Quality Standard ◽  
Average Concentration ◽  
Air Pollutant ◽  
Control Measures ◽  
Ozone Pollution ◽  
Pm2.5 And Pm10

Abstract. Improving the air quality in China is a long and arduous task. Although China has made very aggressive plans for air pollutant control, the difficulties in achieving the new air quality goals are still significant. A lot of cities are developing their implementation plan (CIP) for new air quality goals. In this study, a southern city, Guangzhou, has been selected to analyze the feasibility and difficulties of new air quality standard compliance, as well as the CIP evaluation. A comprehensive study of the air quality status in Guangzhou and the surrounding area was conducted using 22 monitoring sites collection data for O3, PM2.5 and PM10. The monthly non-attainment rates for O3 vary from 7 to 25% for May to November. The city average PM2.5 concentration was 53 μg m−3 in Guangzhou in 2010, which needs to be reduced by at least 34% to achieve the target of 35 μg m−3. The PM2.5 high violation months are from November to March. A CIP was developed for Guangzhou, which focused on PM2.5. Based on the CIP, the emission amounts of NOx, PM10, PM2.5 and volatile organic compounds (VOCs) in 2025 would be controlled to 119, 61, 26 and 163 thousand tons, respectively, reduced by 51.9%, 55.9%, 61.8% and 41.3%, respectively, compared to 2010. Analysis of air quality using the model MM5-STEM suggests that the long-term control measures would achieve the PM2.5 and PM10 goals successfully by 2025. The PM2.5 annual average concentration would be reduced to 27 μg m−3 in 2025. However, such PM2.5-based emission control scenarios may enhance the ozone pollution problems. The O3 non-attainment rate would increase from 7.1% in 2010 to 12.9% in 2025, implying that ozone will likely become a major compliance issue with the new national ambient air quality standards (NAAQS). This suggests that O3 control must be taken into account while designing PM2.5 control strategies, especially PM2.5 compliance under increased atmospheric oxidation, and for VOCs / NOx reduction ratios need to be further investigated, in order to eventually achieve O3–PM2.5 co-improvement in this region or other cities.

scholarly journals Changes in summertime ozone in Colorado during 2000–2015

Elem Sci Anth ◽  
2018 ◽  
Vol 6 ◽  
Author(s):  
Tanja Bien ◽  
Detlev Helmig
Keyword(s):  
Air Quality ◽  
Urban Areas ◽  
Oil And Gas ◽  
Ambient Air ◽  
Quality Standard ◽  
P Value ◽  
Nox Emissions ◽  
Mixing Ratios ◽  
June July ◽  
Surface O3

In 2016, the Denver Metro Area (DMA)/Northern Colorado Front Range (NCFR) was reclassified from a Marginal to a Moderate O3 Non-Attainment Area due to the prevalence of high summer ozone (O3) occurrences. Hourly surface O3 data collected during 2000–2015 from a total of 80 monitoring sites in the State of Colorado were investigated for geographical features in O3 behavior and O3 changes over time. We particularly focus on summer O3 (June, July, August), which is the time when most exceedances of the O3 National Ambient Air Quality Standard (NAAQS) have been recorded. Variables investigated include the statistical (5th, 50th (median), and 95th percentile) distribution of O3 mixing ratios, diurnal amplitudes, and their trends. Trend analyses were conducted for 20 site records that had at least ten years of data. The majority of Colorado ozone monitoring sites show an increase of the 5th (16 total; 11 of these are statistically significant (p-value ≤ 0.05) trends) and 50th (15 total; 4 statistically significant trends) percentile values. Changes for the 95th percentile values were smaller and less consistent. One site showed a statistically significant declining trend, and one site an increasing trend; the majority of other sites had slightly negative, albeit not statistically significant declining O3. Ozone changes at the two highest elevations sites (&gt;2500 m asl) are all negative, contrasting increasing O3 at U.S. West Coast sites. NCFR urban sites do not show the rate of decreasing higher percentile O3 as seen for the majority of urban areas across the U.S. during the past 1–2 decades. The amplitudes of diurnal O3 cycles were studied as a proxy for nitrogen oxides (NOx) emissions and the diurnal O3 production chemistry. The majority of sites show a decrease in the median summer O3 diurnal amplitude (19 total/10 statistically significant). This is mostly driven by the increase in nighttime O3 minima, which is most likely a sign for a declining rate of nighttime O3 loss from titration with nitric oxide (NO), indicating a change in O3 behavior from declining NOx emissions. Since median and upper percentile surface O3 values in the DMA have not declined at the rates seen in other western U.S. regions, thus far the reduction in NOx has had a more pronounced effect on the lower percentile O3 distribution than on high O3 occurrences that primarily determine air quality. An assessment of the influence of oil and gas emissions on Colorado, and in particular DMA O3, is hampered by the sparsity of monitoring within oil and gas basins. Continuous, long-term, high quality, and co-located O3, NOx, and VOC monitoring are recommended for elucidating the geographical heterogeneity of O3 precursors, their changing emissions, and for evaluation of the effectiveness of O3 air quality regulations.

scholarly journals Atmospheric Aerosols: Air Quality and Climate Change Perspectives

2015 ◽  
Vol 10 (3) ◽  
pp. 738-746 ◽  
Author(s):  
Shabana Manzoor ◽  
Umesh Kulshrestha
Keyword(s):  
Air Quality ◽  
Atmospheric Aerosols ◽  
Urban Areas ◽  
Ambient Air ◽  
Quality Standard ◽  
Vital Role ◽  
Cloud Formation ◽  
Pm10 And Pm2.5 ◽  
Suspended Particulate ◽  
Ambient Air Quality Standard

Recently, air quality has become a matter of concern of everyone. According to the reports, atmospheric aerosols play very crucial role in air quality. PM10 and PM2.5 aerosols are integral parts of total suspended particulate matter which affect our health. Often air quality has been reported very poor due to violation of National Ambient Air Quality Standard (NAAQS) limits. PM10 and PM2.5 limits are crossed for both residential as well as sensitive sites. This is one of the major reasons of increasing cases of respiratory diseases in urban areas. However, aerosol loadings alone are not the factor for deciding or predicting toxic and harmful effects of aerosols. Chemical composition and size ranges do matter. Aerosol loadings can be due to three major source categories viz. marine, crustal and anthropogenic. Since, marine and crustal content of aerosols are generally non-toxic and hence, degree of toxicity of air needs to be decided on the basis of anthropogenic fraction having metals, PAHs and other harmful content. Apart from air quality and health, atmospheric aerosols play vital role in other atmospheric processes such as cloud formation, radiative transfer and monsoon etc. Though there are several studies reported on different aspects of atmospheric aerosols, but most of the findings are sort of data reporting based on short term observations. Hence, there is need to investigate the atmospheric aerosols in order to demonstrate local and regional phenomenon on the basis of long term datasets.

scholarly journals Winter Ozone Pollution in Utah’s Uinta Basin is Attenuating

Atmosphere ◽  
2020 ◽  
Vol 12 (1) ◽  
pp. 4
Author(s):  
Marc L. Mansfield ◽  
Seth N. Lyman
Keyword(s):  
Ground Level ◽  
Ambient Air ◽  
Quality Standard ◽  
Ozone Pollution ◽  
Uinta Basin ◽  
Concentration Data ◽  
Previous Decade ◽  
High Concentrations ◽  
Ambient Air Quality Standard ◽  
Ozone Precursor

High concentrations of ground-level ozone have been observed during wintertime in the Uinta Basin of western Utah, USA, beginning in 2010. We analyze existing ozone and ozone precursor concentration data from 38 sites over 11 winter seasons and conclude that there has been a statistically significant (p < 0.02) decline in ozone concentration over the previous decade. Daily exceedances of the National Ambient Air Quality Standard for ozone (70 ppb) have been trending downward at the rate of nearly four per year. Ozone and NOx concentrations have been trending downward at the rates of about 3 and 0.3 ppb per year, respectively. Concentrations of organics in 2018 were at about 30% of their values in 2012 or 2013. Several markers, annual ozone exceedance counts and median ozone and NOx concentrations, were at their largest values in the period 2010 to 2013 and have never recovered since then. We attribute the decline to (1) weakening global demand for oil and natural gas and (2) more stringent pollution regulations and controls, both of which have occurred over the previous decade. We also see evidence of ozone titration when snow cover is absent.

scholarly journals Modelling the impact of megacities on local, regional and global tropospheric ozone and the deposition of nitrogen species

2013 ◽  
Vol 13 (24) ◽  
pp. 12215-12231 ◽  
Author(s):  
Z. S. Stock ◽  
M. R. Russo ◽  
T. M. Butler ◽  
A. T. Archibald ◽  
M. G. Lawrence ◽  
...  
Keyword(s):  
Air Quality ◽  
Urban Areas ◽  
Climate Model ◽  
Surface Ozone ◽  
Global Scale ◽  
Chemical Environment ◽  
Ozone Production ◽  
The Uk ◽  
The Impact ◽  
Local Emissions

Abstract. We examine the effects of ozone precursor emissions from megacities on present-day air quality using the global chemistry–climate model UM-UKCA (UK Met Office Unified Model coupled to the UK Chemistry and Aerosols model). The sensitivity of megacity and regional ozone to local emissions, both from within the megacity and from surrounding regions, is important for determining air quality across many scales, which in turn is key for reducing human exposure to high levels of pollutants. We use two methods, perturbation and tagging, to quantify the impact of megacity emissions on global ozone. We also completely redistribute the anthropogenic emissions from megacities, to compare changes in local air quality going from centralised, densely populated megacities to decentralised, lower density urban areas. Focus is placed not only on how changes to megacity emissions affect regional and global NOx and O3, but also on changes to NOy deposition and to local chemical environments which are perturbed by the emission changes. The perturbation and tagging methods show broadly similar megacity impacts on total ozone, with the perturbation method underestimating the contribution partially because it perturbs the background chemical environment. The total redistribution of megacity emissions locally shifts the chemical environment towards more NOx-limited conditions in the megacities, which is more conducive to ozone production, and monthly mean surface ozone is found to increase up to 30% in megacities, depending on latitude and season. However, the displacement of emissions has little effect on the global annual ozone burden (0.12% change). Globally, megacity emissions are shown to contribute ~3% of total NOy deposition. The changes in O3, NOx and NOy deposition described here are useful for quantifying megacity impacts and for understanding the sensitivity of megacity regions to local emissions. The small global effects of the 100% redistribution carried out in this study suggest that the distribution of emissions on the local scale is unlikely to have large implications for chemistry–climate processes on the global scale.

Sign in / Sign up

Export Citation Format

Share Document