Monitoring of Atmospheric Pollutant Concentrations in the City of Dakar, Senegal

Baïdy Sow; Bertrand Tchanche; Ibrahima Fall; Saliou Souaré; Aminata Mbow-Diokhané

doi:10.4236/ojap.2021.101002

Development and Application of an Atmospheric Pollutant Monitoring System Based on LoRa—Part I: Design and Reliability Tests

Sensors ◽

10.3390/s18113891 ◽

2018 ◽

Vol 18 (11) ◽

pp. 3891 ◽

Cited By ~ 2

Author(s):

Yushuang Ma ◽

Long Zhao ◽

Rongjin Yang ◽

Xiuhong Li ◽

Qiao Song ◽

...

Keyword(s):

Embedded System ◽

Communication Technology ◽

Atmospheric Pollutant ◽

Practical Applications ◽

Actual Application ◽

Pollutant Concentrations ◽

Application Data ◽

Software And Hardware ◽

The Internet Of Things ◽

Monitoring Platform

At present, as growing importance continues to be attached to atmospheric environmental problems, the demand for real-time monitoring of these problems is constantly increasing. This article describes the development and application of an embedded system for monitoring of atmospheric pollutant concentrations based on LoRa (Long Range) wireless communication technology, which is widely used in the Internet of Things (IoT). The proposed system is realized using a combination of software and hardware and is designed using the concept of modularization. Separation of each function into independent modules allows the system to be developed more quickly and to be applied more stably. In addition, by combining the requirements of the remote atmospheric pollutant concentration monitoring platform with the specific requirements for the intended application environment, the system demonstrates its significance for practical applications. In addition, the actual application data also verifies the sound application prospects of the proposed system.

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The global impacts of COVID-19 lockdowns on urban air pollution

Elem Sci Anth ◽

10.1525/elementa.2021.00176 ◽

2021 ◽

Vol 9 (1) ◽

Author(s):

Georgios I. Gkatzelis ◽

Jessica B. Gilman ◽

Steven S. Brown ◽

Henk Eskes ◽

A. Rita Gomes ◽

...

Keyword(s):

Atmospheric Chemistry ◽

Urban Air Pollution ◽

Future Research ◽

Specific Method ◽

Data Sets ◽

Atmospheric Pollutant ◽

Government Interventions ◽

Pollutant Concentrations ◽

Global Impacts ◽

The Government

The coronavirus-19 (COVID-19) pandemic led to government interventions to limit the spread of the disease which are unprecedented in recent history; for example, stay at home orders led to sudden decreases in atmospheric emissions from the transportation sector. In this review article, the current understanding of the influence of emission reductions on atmospheric pollutant concentrations and air quality is summarized for nitrogen dioxide (NO2), particulate matter (PM2.5), ozone (O3), ammonia, sulfur dioxide, black carbon, volatile organic compounds, and carbon monoxide (CO). In the first 7 months following the onset of the pandemic, more than 200 papers were accepted by peer-reviewed journals utilizing observations from ground-based and satellite instruments. Only about one-third of this literature incorporates a specific method for meteorological correction or normalization for comparing data from the lockdown period with prior reference observations despite the importance of doing so on the interpretation of results. We use the government stringency index (SI) as an indicator for the severity of lockdown measures and show how key air pollutants change as the SI increases. The observed decrease of NO2 with increasing SI is in general agreement with emission inventories that account for the lockdown. Other compounds such as O3, PM2.5, and CO are also broadly covered. Due to the importance of atmospheric chemistry on O3 and PM2.5 concentrations, their responses may not be linear with respect to primary pollutants. At most sites, we found O3 increased, whereas PM2.5 decreased slightly, with increasing SI. Changes of other compounds are found to be understudied. We highlight future research needs for utilizing the emerging data sets as a preview of a future state of the atmosphere in a world with targeted permanent reductions of emissions. Finally, we emphasize the need to account for the effects of meteorology, emission trends, and atmospheric chemistry when determining the lockdown effects on pollutant concentrations.

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Analiza zmian jakości powietrza Małopolski w latach 2012–2020

Nafta-Gaz ◽

10.18668/ng.2020.11.11 ◽

2020 ◽

Vol 76 (11) ◽

pp. 854-854

Author(s):

Mateusz Rataj ◽

◽

Jadwiga Holewa-Rataj ◽

Keyword(s):

Air Quality ◽

Measurement Data ◽

Limit Values ◽

Individual Measurement ◽

Dust Emissions ◽

National Centre ◽

Pollutant Concentrations ◽

Polish Law ◽

Air Quality Monitoring Stations ◽

The City

The article focuses on the problem of air pollution, which is referred to as smog, which, according to the WHO, causes the death of 4.2 million people annually. In Europe, the problem of smog particularly affects Poland, according to WHO data, among the 50 most polluted European cities, as many as 33 are in Poland. Out of concern for the health of the residents, Polish law has given local authorities the opportunity to introduce anti-smog resolutions. Anti-smog resolutions focus mainly on reducing dust emissions from the municipal and housing sector, and according to the data of the National Centre for Balancing and Emissions Management, it is responsible for approximately 49% of dust emissions into the atmosphere in Poland. Małopolska also adopted anti-smog resolutions in 2016 (for the city of Kraków) and 2017 (for the remaining area of the voivodeship). Nevertheless, actions under the implementation of air protection programs in Małopolska have been undertaken much earlier. In the years 2013–2018, 43.6 thousand boilers and stoves using solid fuels were decommissioned in Małopolska, including 22.5 thousand in Kraków alone. The article analyzes the changes in air quality in Małopolska in the years 2012–2020. The data analysis focused on five basic pollutants included in smog (i.e. PM10 and PM2.5 dust, nitrogen oxides, sulfur dioxide and carbon monoxide) and the readings of 8 air quality monitoring stations (3 located in the city of Krakow and 5 stations located outside Krakow). The main purpose of the analysis was to show whether the measures taken in Małopolska lead to the improvement of air quality. For this purpose, both changes in daily average and annual average pollutant concentrations recorded by individual measurement stations, as well as changes in the number of days in the heating season in which the limit values were exceeded were analyzed. The analysis of the available measurement data for the years 2012–2020 clearly showed that there are pollutants for which the permissible content in the air is exceeded many times a year throughout the voivodeship. At the same time, in the analyzed period, there are noticeable decreasing trends in the observed concentrations of individual pollutants in the air, which proves that the measures taken in Małopolska to improve air quality are slowly bringing results.

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Ecological Quality of Natural Waters from of Kharkiv Urban Springs

Man and Environment. Issues of Neoecology ◽

10.26565/1992-4224-2019-31-09 ◽

2019 ◽

Keyword(s):

Water Samples ◽

Natural Waters ◽

Electrical Potential ◽

Field Research ◽

Water Hardness ◽

Atomic Absorption Spectrophotometry ◽

Nitrate Content ◽

Pollutant Concentrations ◽

Rigidity Index ◽

The City

Purpose. Estimation of ecological safety of spring waters of the city of Kharkiv. Methods. Field research, atomic absorption spectrophotometry, analytical methods for studying water quality indicators. Results. Natural water samples were analyzed on the following parameters: pH, electrical potential, nitrate content, chlorides, ammonia, transparency, turbidity, and water hardness. The highest values of the content of nitrates, nitrites, as well as the level of alkalinity and rigidity were found in a sample from the Kholodnogorsk spring. In the water from the Zhukovsky spring the high content of chlorides is found, which is one and a half times higher than the concentration in water from other city springs. In the water from the Glyboky Yar spring the lowest mineralization of water was detected, and in the water from the Sarzhin Yar spring - the highest of the studied samples of water from the natural springs of Kharkiv. However, all identified pollutant concentrations except for the rigidity index is not dangerous for a person, because they are not exceeded by the MAC. The results of research on water samples from the Sarzhin Yar spring and from the spring in Yunost park (Kholodnogorsk source) in 2019, compared to the results of a similar study conducted in 2015. It was determined that in the water from the Sarzhin Yar spring the rigidity index increased 3.4 times, and in the sample from the spring in Yunost park (Kholodnogorsk spring) almost 6 times. Conclusions. It is determined that in the territory of the city of Kharkiv, water from the Zhukovskii spring in the Kyivskiy district is fully suitable for consumption, because its chemical composition is fully in line with the sanitary norms that apply to drinking spring waters. The value of the level of hardness of water in all samples, except Zhukovsky spring, indicate that the normative value exceeds 2-3 times. The rigidity of drinking water that exceeds the MAC may adversely affect human health. Therefore, the only ecologically safe, among the investigated, can be considered water from the Zhukovsky spring (Kievskiy district in Kharkiv). For other sources, it is recommended to modernize the water collection sites for the population, reconstruct the system of water supply for the supply of water from these sources, as well as to introduce additional stages of their treatment on the way to the consumer.

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Investigation of local meteorological events and their relationship with ozone and aerosols during an ESCOMPTE photochemical episode

Annales Geophysicae ◽

10.5194/angeo-24-2809-2006 ◽

2006 ◽

Vol 24 (11) ◽

pp. 2809-2822 ◽

Cited By ~ 13

Author(s):

P. Augustin ◽

H. Delbarre ◽

F. Lohou ◽

B. Campistron ◽

V. Puygrenier ◽

...

Keyword(s):

Transit Time ◽

Prediction Models ◽

Sea Breeze ◽

City Centre ◽

Breeze Circulation ◽

Sea Breezes ◽

Pollutant Concentrations ◽

Time Space ◽

Marine Air ◽

The City

Abstract. The international ESCOMPTE campaign, which took place in summer 2001 in the most highly polluted French region, was devoted to validate air pollution prediction models. Surface and remote sensing instruments (Lidar, Radar and Sodar) were deployed over the Marseille area, along the Mediterranean coast, in order to investigate the fine structure of the sea-breeze circulation and its relationship with the pollutant concentrations. The geographical situation of the Marseille region combines a complex coastline and relief which both lead to a peculiar behaviour of the sea-breeze circulation. Several local sea breezes, perpendicular to the nearest coastline, settled in during the morning. In the afternoons, when the thermal gradient between the continental and marine surface grows up, a southerly or a westerly sea breeze may dominate. Their respective importance is then a function of time, space and altitude. Furthermore, an oscillation of the westerly sea breeze with a period of about 3 h is also highlighted. We show that these dynamical characteristics have profound influences on the atmospheric boundary-layer (ABL) development and on pollutant concentrations. In fact, the direction and intensity of the sea-breeze determine the route and the transit time of the stable marine air flow over the continental surface. Thus, the ABL depth may exhibit several collapses correlated with the westerly sea-breeze pulsation. The ozone and aerosol concentrations are also related to the dynamical features. In the suburbs and parts of the city under pulsed sea breezes, a higher ABL depth and higher ozone concentrations are observed. In the city centre, this relationship between pulsed sea-breeze intensity and ozone concentration is different, emphasising the importance of the transit time and also the build-up of pollutants in the marine air mass along the route. Finally, the variations of aerosol concentration are also described according to the breeze direction.

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Developing a Smartphone Software Package for Predicting Atmospheric Pollutant Concentrations at Mobile Locations

The Computer Journal ◽

10.1093/comjnl/bxu067 ◽

2014 ◽

Vol 58 (6) ◽

pp. 1431-1442 ◽

Cited By ~ 9

Author(s):

A. Larkin ◽

D. E. Williams ◽

M. L. Kile ◽

W. M. Baird

Keyword(s):

Software Package ◽

Atmospheric Pollutant ◽

Pollutant Concentrations

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Analysis of Air Pollutant concentration change trend in Urumqi city under the condition of city closed in winter

E3S Web of Conferences ◽

10.1051/e3sconf/202123701037 ◽

2021 ◽

Vol 237 ◽

pp. 01037

Author(s):

Haizhen Zhang ◽

Jiang Wei

Keyword(s):

Air Pollutant ◽

Pollutant Concentration ◽

Atmospheric Environment ◽

Pollutant Emission ◽

Energy Control ◽

Positive Role ◽

Atmospheric Pollutant ◽

Epidemic Period ◽

The City

During the epidemic period, Urumqi has been sealed off from the city’s management, just as “suspended” state.From an environmental point of view, the reduction of energy consumption during the closure of the city can be considered as an energy control to study the resulting reduction of atmospheric pollutant concentration changes.In this paper, the monitoring data of air pollutant concentration in the same period of city closure and normal years are compared, and the results show that the air pollutant concentration has decreased in different degrees during the period of city closure.The largest decrease was44.66% for NO2, -40.13% for CO, -36.44% for PM2.5, and the smallest was-2.06% for SO2.Multivariate analysis of variance showed that energy control had a significant effect on the concentration of pollutants during the city closure, for example NO2 (F=128.96, Sig.=0.000), PM10 (F=29.58, Sig=0.000), PM2.5 (F=13.98, Sig.=0.000), CO(F=46.34;Sig.=0.000). Through the analysis of the data, it can be concluded that the air quality of Urumqi in winter is poor and the concentration of pollutants is high. The energy control during the closing period played a positive role in pollutant emission reduction and effectively improved the quality of atmospheric environment.

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Mid-21st century air quality at the urban scale under the influence of changed climate and emissions: case studies for Paris and Stockholm

Atmospheric Chemistry and Physics Discussions ◽

10.5194/acpd-15-27041-2015 ◽

2015 ◽

Vol 15 (19) ◽

pp. 27041-27085

Author(s):

K. Markakis ◽

M. Valari ◽

M. Engardt ◽

G. Lacressonnière ◽

R. Vautard ◽

...

Keyword(s):

Climate Change ◽

Urban Areas ◽

Large Scale ◽

Regional Scale ◽

Influential Factor ◽

Daily Average ◽

Pollutant Concentrations ◽

Emission Projections ◽

The Impact ◽

The City

Abstract. Ozone, PM10 and PM2.5 concentrations over Paris, France and Stockholm, Sweden were modeled at 4 and 1 \\unit{km} horizontal resolutions respectively for the present and 2050 periods employing decade-long simulations. We account for large-scale global climate change (RCP-4.5) and fine resolution bottom-up emission projections developed by local experts and quantify their impact on future pollutant concentrations. Moreover, we identify biases related to the implementation of regional scale emission projections over the study areas by comparing modeled pollutant concentrations between the fine and coarse scale simulations. We show that over urban areas with major regional contribution (e.g., the city of Stockholm) the bias due to coarse emission inventory may be significant and lead to policy misclassification. Our results stress the need to better understand the mechanism of bias propagation across the modeling scales in order to design more successful local-scale strategies. We find that the impact of climate change is spatially homogeneous in both regions, implying strong regional influence. The climate benefit for ozone (daily average and maximum) is up to −5 % for Paris and −2 % for Stockholm city. The joined climate benefit on PM2.5 and PM10 in Paris is between −10 and −5 % while for Stockholm we observe mixed trends up to 3 % depending on season and size class. In Stockholm, emission mitigation leads to concentration reductions up to 15 % for daily average and maximum ozone and 20 % for PM and through a sensitivity analysis we show that this response is entirely due to changes in emissions at the regional scale. On the contrary, over the city of Paris (VOC-limited photochemical regime), local mitigation of NOx emissions increases future ozone concentrations due to ozone titration inhibition. This competing trend between the respective roles of emission and climate change, results in an increase in 2050 daily average ozone by 2.5 % in Paris. Climate and not emission change appears to be the most influential factor for maximum ozone concentration over the city of Paris, which may be particularly interesting in a health impact perspective.

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Assessing the environmental impact of WWTP expansion: odour nuisance and its minimization

Water Science & Technology ◽

10.2166/wst.2002.0620 ◽

2002 ◽

Vol 46 (4-5) ◽

pp. 339-346 ◽

Cited By ~ 4

Author(s):

A.G. Capodaglio ◽

F. Conti ◽

L. Fortina ◽

G. Pelosi ◽

G. Urbini

Keyword(s):

Air Quality Modelling ◽

Drastic Reduction ◽

Wastewater Disposal ◽

Slowing Down ◽

Pollutant Concentrations ◽

Final Design ◽

Modelling Techniques ◽

Total Capacity ◽

The One ◽

The City

As part of the effort to provide proper wastewater disposal for the City of Milan, the expansion of the WWTP located in Peschiera Borromeo has been planned and is currently under completion. The plant, sized for a population of less than 300,000, will soon treat the wastes from the south-east areas of Milan for a total capacity of over 500,000 p.e. The paper describes the approach to find a satisfactory solution of an alleged odour problem that is slowing down the completion of the plant restructuring. This included a survey of the existing plant and analysis of its final design, identification of odour emission sources and their quantification, and the examination of different alternatives for odour abatement. These were carried out using air quality modelling techniques consisting of dynamic, continuous “puff” models capable of reproducing diffusion even at very low pollutant concentrations. Several intervention hypotheses were tested and compared with the few existing regulatory norms and guidelines for odour pollution. In all but the minimum and the no-action hypotheses, proposed actions would results in a drastic reduction of nuisance effects at the receptors. Under the strongest intervention hypothesis (the one adopted by the WWTP agency), odour impact would be virtually eliminated.

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Impacts of COVID-19 lockdown restrictions on urban NO2 and O3 level in Germany with consideration of meteorological impacts and seasonal variation

10.5194/egusphere-egu21-12035 ◽

2021 ◽

Author(s):

Vigneshkumar Balamurugan ◽

Xiao Bi ◽

Johannes Gensheimer ◽

Jia Chen ◽

Frank Keutsch ◽

...

Keyword(s):

Sunshine Duration ◽

Meteorological Conditions ◽

Photochemical Reactions ◽

Pollutant Emission ◽

World Population ◽

Emission Rates ◽

Atmospheric Pollutant ◽

Marginal Change ◽

Pollutant Concentrations ◽

Business As Usual

In 2020, the entire world population has witnessed an unprecedented virus outbreak in terms of COVID-19, which led to restrictions in human activities across the world. Strict measures in Germany started on March-21, 2020 and ended on April-30, 2020, while more relaxed measures continued until July 2020. Vehicle traffic volume and industrial activities were drastically reduced, and, as a result, pollutant emission rates were expected to be reduced. Changes in atmospheric pollutant concentrations are an indicator for changes in emission rates although they are not directly proportional as concentrations are heavily influenced by meteorological conditions and as atmospheric photochemical reactions can be non-linear. Without accounting for the influence of meteorology and atmospheric photochemical reactions, a simple comparison of the lockdown period pollutant concentration values with pre-lockdown only to estimate emissions could be misleading. To normalize the effects of meteorological conditions and atmospheric chemical transformation and reactions, we adopted a method of comparing the predicted Business As Usual (BAU) NO2 and O3 concentrations, i.e., the expected value of NO2 and O3 concentration for 2020 meteorological conditions without lockdown restrictions, with the observed NO2 and O3 concentrations. BAU NO2 and O3 concentrations corresponding to 2020 meteorological conditions were predicted based on wind speed and sunshine duration (and season of the day) using the previous year NO2 and O3 concentrations as the references. Compared to BAU levels, big metropolitan cities in Germany show a decline in observed NO2 level (-24.5 to -37.7 %) in the strict lockdown period and rebound to the BAU level at the end of July 2020. In contrast, there is a marginal change in O3 level (+9.6 to -7.4 %). We anticipate that the imbalanced changes in precursors emission (decrease in NOX and increase in volatile organic compounds (VOCs) emission) are attributed to the marginal changes in observed O3 level compared to BAU level; decreased NOX would decrease the O3 concentration due to NOX-limited conditions, and increased VOCs would increase the O3 concentration. These results imply that the balanced emission control between the VOCs and NOX are required to limit the secondary pollutant (O3) formation.

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