On the impact of temperature on tropospheric ozone concentration levels in urban environments

Tropospheric ozone is a greenhouse gas, and high tropospheric ozone levels can directly impact plant growth and human health. In the Congo basin, simulations predict high ozone concentrations, induced by high ozone precursor (VOC and NOx) concentrations and high solar irradiation, which trigger the chemical reactions that form ozone. Additionally, biomass burning activities are widespread on the African continent, playing a crucial role in ozone precursor production. How these potentially high ozone levels impact tropical forest primary productivity remains poorly understood, and field-based ozone monitoring is completely lacking from the Congo basin. This study intends to show preliminary results from the first full year of in situ measurements of ozone concentration in the Congo Basin (i.e., Yangambi, Democratic Republic of the Congo). We show the relationships between meteorological variables (temperature, precipitation, radiation, wind direction and speed), fire occurrence (derived from remote sensing products) and ozone concentrations at a new continuous monitoring station in the heart of the Congo Basin. First results show higher daily mean ozone levels (e.g. 43 ppb registered in January 2020) during dry season months (December-February). We identify a strong diurnal cycle, where minimum values of ozone (almost near zero) are registered during night hours, and maximum values (near 100 ppb) are registered during the daytime. We also verify that around 2.5% of the ozone measurements exceeds a toxicity level (potential for ozone to damage vegetation) of 40 ppb. In the longer term, these measurements should improve the accuracy of future model simulations in the Congo Basin and will be used to assess the impact of ozone on the tropical forest&#8217;s primary productivity.

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Variation of the surface ozone concentration during precipitation

10.5194/egusphere-egu2020-6862 ◽

2020 ◽

Author(s):

Igor V. Ptashnik ◽

Boris D. Belan ◽

Denis E. Savkin ◽

Gennadii N. Tolmachev ◽

Tatayana K. Sklyadneva ◽

...

Keyword(s):

Diurnal Variation ◽

Ozone Concentration ◽

Tropospheric Ozone ◽

Surface Ozone ◽

Chem Phys ◽

Global Scale ◽

Washington Dc ◽

American Geophysical ◽

The Impact ◽

Surface Ozone Concentration

In the review compiled by Monks et al. (2015), it is noted that the main variations in the tropospheric ozone are determined by the exchange between the troposphere and the stratosphere, in-situ photochemical production from gaseous precursors depending on their composition and concentration, solar radiation income, and meteorological conditions. The impact of precipitation on the surface ozone concentration is a less well-studied factor.The process of ozone interaction with precipitation was studied theoretically (Heicklen, 1982). Two ways of the above process were analyzed: adsorption of gas molecules on the surface of a particle and a chemical reaction with its surface. There are no direct data on the verification of these findings in the literature. At the same time, there is some evidence of a possible link between precipitation and ozone.This study is aimed to analyze the presence or absence of changes in the ozone concentration during precipitation. Variations of the surface ozone concentration (SOC) in the presence of precipitation were analyzed using the long-term data obtained at the TOR-station established in 1992 for ozone monitoring in Tomsk. It was revealed that these changes can be both positive (increase in concentration) and negative. The sharp changes in the SOC are observed when frontal precipitation takes place. In the presence of air-mass precipitation, the sign and magnitude of the change is determined by the diurnal variation of ozone concentration.The analysis showed a coincidence of the SOC growth during precipitation with its increase in diurnal variation in 59% of cases. The coincidence in the wave of the concentration decline in the diurnal variation with decreasing precipitation rate is even higher and amounts to 85%.Airborne sounding carried out in the vicinity of the TOR-station shown that in a number of cases the ozone deposition from the boundary layer is observed upon the transition of thermal stratification during the precipitation to neutral.&#160;Monks P. S, Archibald A. T., Colette A., Cooper O., Coyle M., Derwent R., Fowler D., Granier C., Law K. S., Mills G. E., Stevenson D. S., Tarasova O., Thouret V., von Schneidemesser E., Sommariva R., Wild O., Williams M. L. Tropospheric ozone and its precursors from the urban to the global scale from air quality to short-lived climate forcer. Atmos. Chem. Phys., 2015, v.15, N15, p.8889&#8211;8973.Heicklen J. The Removal of Atmospheric Gases by Particulate Matter. In Heterogeneous Atmospheric&#160;Chemistry, ed. D. R.&#160;Schryer, Geophysical Monograph 26. American Geophysical Union, Washington, DC, USA, 1982, p. 93-98.

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Evolution of Tropospheric Ozone and Relationship with Temperature and NOx for the 2007-2016 Decade in the Ciuc Depression

Revista de Chimie ◽

10.37358/rc.18.3.6158 ◽

2018 ◽

Vol 69 (3) ◽

pp. 602-608

Author(s):

Sandor Petres ◽

Szabolcs Lanyi ◽

Marisanda Pirianu ◽

Agnes Keresztesi ◽

Aurelia Cristina Nechifor

Keyword(s):

Ozone Concentration ◽

Tropospheric Ozone ◽

Climate Changes ◽

Extreme Temperature ◽

Factors Influencing ◽

Penalty Factor ◽

Main Factors ◽

Temperature Indices ◽

The Impact ◽

The Relationship

This paper presents the evolution of ozone concentration for the 2007-2016 decade and a comparison with key values related to human and vegetation health. As temperature is one of the main factors influencing ozone concentration in this area, the most significant changes of air temperature and extreme temperature indices for the 2007 - 2016 decade were evaluated, in retrospect to temperature measurements for the 1961-1990 reference period. The relationship between temperature and ozone concentration was also overviewed, by means of climate penalty factor. The influence of NOx concentration on ozone concentration was studied in order to compare the impact of climate changes with the impact of changes determined by anthropogenic emission.

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Assessment and prediction of tropospheric ozone concentration levels using artificial neural networks

Environmental Modelling & Software ◽

10.1016/s1364-8152(01)00077-9 ◽

2002 ◽

Vol 17 (3) ◽

pp. 219-228 ◽

Cited By ~ 118

Author(s):

S.A Abdul-Wahab ◽

S.M Al-Alawi

Keyword(s):

Neural Networks ◽

Artificial Neural Networks ◽

Ozone Concentration ◽

Tropospheric Ozone ◽

Artificial Neural ◽

Concentration Levels

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The influence of African air pollution on regional and global tropospheric ozone

Atmospheric Chemistry and Physics ◽

10.5194/acp-7-1193-2007 ◽

2007 ◽

Vol 7 (5) ◽

pp. 1193-1212 ◽

Cited By ~ 59

Author(s):

A. M. Aghedo ◽

M. G. Schultz ◽

S. Rast

Keyword(s):

Central Asia ◽

Biomass Burning ◽

Ozone Concentration ◽

Tropospheric Ozone ◽

Surface Ozone ◽

The United States ◽

Biogenic Emissions ◽

Anthropogenic Emissions ◽

The Impact ◽

Surface Ozone Concentration

Abstract. We investigate the influence of African biomass burning, biogenic, lightning and anthropogenic emissions on the tropospheric ozone over Africa and globally using a coupled global chemistry climate model. Our model studies indicate that surface ozone concentration may rise by up to 50 ppbv in the burning region during the biomass burning seasons. Biogenic emissions yield between 5–30 ppbv increase in the near surface ozone concentration over tropical Africa. The impact of lightning on surface ozone is negligible, while anthropogenic emissions yield a maximum of 7 ppbv increase in the annual-mean surface ozone concentration over Nigeria, South Africa and Egypt. Our results show that biogenic emissions are the most important African emission source affecting total tropospheric ozone. The influence of each of the African emissions on the global tropospheric ozone burden (TOB) of 384 Tg yields about 9.5 Tg, 19.6 Tg, 9.0 Tg and 4.7 Tg for biomass burning, biogenic, lightning and anthropogenic emissions emitted in Africa respectively. The impact of each of these emission categories on African TOB of 33 Tg is 2.5 Tg, 4.1 Tg, 1.75 Tg and 0.89 Tg respectively, which together represents about 28% of the total TOB calculated over Africa. Our model calculations also suggest that more than 70% of the tropospheric ozone produced by each of the African emissions is found outside the continent, thus exerting a noticeable influence on a large part of the tropical troposphere. Apart from the Atlantic and Indian Ocean, Latin America experiences the largest impact of African emissions, followed by Oceania, the Middle East, Southeast and south-central Asia, northern North America (i.e. the United States and Canada), Europe and north-central Asia, for all the emission categories.

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Urban Heat Islands and Thermal Comfort: A Case Study of Zorrotzaurre Island in Bilbao

Sustainability ◽

10.3390/su13116106 ◽

2021 ◽

Vol 13 (11) ◽

pp. 6106

Author(s):

Irantzu Alvarez ◽

Laura Quesada-Ganuza ◽

Estibaliz Briz ◽

Leire Garmendia

Keyword(s):

Thermal Comfort ◽

Heat Waves ◽

Urban Environments ◽

Urban Heat Islands ◽

Extreme Weather Events ◽

Climate Index ◽

Physiological Equivalent Temperature ◽

Heat Islands ◽

The North ◽

The Impact

This study assesses the impact of a heat wave on the thermal comfort of an unconstructed area: the North Zone of the Island of Zorrotzaurre (Bilbao, Spain). In this study, the impact of urban planning as proposed in the master plan on thermal comfort is modeled using the ENVI-met program. Likewise, the question of whether the urbanistic proposals are designed to create more resilient urban environments is analyzed in the face of increasingly frequent extreme weather events, especially heat waves. The study is centered on the analysis of temperature variables (air temperature and average radiant temperature) as well as wind speed and relative humidity. This was completed with the parameters of thermal comfort, the physiological equivalent temperature (PET) and the Universal Temperature Climate Index (UTCI) for the hours of the maximum and minimum daily temperatures. The results demonstrated the viability of analyzing thermal comfort through simulations with the ENVI-met program in order to analyze the behavior of urban spaces in various climate scenarios.

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The ground-level ozone concentration is inversely correlated with the number of COVID-19 cases in Warsaw, Poland

Air Quality Atmosphere & Health ◽

10.1007/s11869-021-01009-7 ◽

2021 ◽

Author(s):

Oskar Wiśniewski ◽

Wiesław Kozak ◽

Maciej Wiśniewski

Keyword(s):

Wind Speed ◽

Ozone Concentration ◽

Inverse Correlation ◽

Ground Level ◽

Viral Agent ◽

The Novel ◽

Weather Factors ◽

Ground Level Ozone ◽

The Many ◽

The Impact

AbstractCOVID-19, which is a consequence of infection with the novel viral agent SARS-CoV-2, first identified in China (Hubei Province), has been declared a pandemic by the WHO. As of September 10, 2020, over 70,000 cases and over 2000 deaths have been recorded in Poland. Of the many factors contributing to the level of transmission of the virus, the weather appears to be significant. In this work, we analyze the impact of weather factors such as temperature, relative humidity, wind speed, and ground-level ozone concentration on the number of COVID-19 cases in Warsaw, Poland. The obtained results show an inverse correlation between ground-level ozone concentration and the daily number of COVID-19 cases.

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Testing the Effect of Hedge Height on Perceived Safety—A Landscape Design Intervention

Sustainability ◽

10.3390/su13095063 ◽

2021 ◽

Vol 13 (9) ◽

pp. 5063

Author(s):

Katinka H. Evensen ◽

Helena Nordh ◽

Ramzi Hassan ◽

Aslak Fyhri

Keyword(s):

Field Study ◽

Field Experiments ◽

Landscape Design ◽

Urban Environments ◽

Space Management ◽

Perceived Safety ◽

Urban Green Spaces ◽

Outdoor Spaces ◽

Surrounding Areas ◽

The Impact

Access to safe, green urban environments is important for quality of life in cities. The objective of this study is to explore the impact of a safety-enhancing landscape design measure on visitors’ experiences in an urban park. Additionally, this paper combines the use of field and virtual reality (VR) experiments, contributing methodological insights into how to evaluate safety measures in green space management and research on perceived safety. In a field experiment (n = 266), we explored whether the height of a hedge along a pathway influenced perceived safety among users. The field study showed that cutting down the hedge improved the perceived prospect of the immediate surrounding areas for female users, which again made them feel safer in the park. We developed a VR experiment for an evening scenario in the same environment (n = 19) to supplement the field study and test the effect of the intervention further. The VR experiment also found a gender effect on perceived safety, with females reporting lower perceived safety, but no effect was shown for the height of the hedge. The results in this study show that environmental attributes such as perceived prospect and concealment should be considered in the design and management of urban green spaces. Additionally, this research demonstrates an approach to conducting field experiments to test the effects of actual design interventions and then further developing these experiments using VR technology. Further research on perceived safety in outdoor spaces is needed to make use of this combined method’s potential.

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A Review of Photocatalytic Materials for Urban NOx Remediation

Catalysts ◽

10.3390/catal11060675 ◽

2021 ◽

Vol 11 (6) ◽

pp. 675

Author(s):

Hugo Savill Russell ◽

Louise Bøge Frederickson ◽

Ole Hertel ◽

Thomas Ellermann ◽

Steen Solvang Jensen

Keyword(s):

Photocatalytic Oxidation ◽

Urban Air Pollution ◽

Field Trials ◽

Urban Environments ◽

Physical Parameters ◽

Nox Removal ◽

Removal Efficiencies ◽

The Impact ◽

By Products ◽

Photocatalytic Materials

NOx is a pervasive pollutant in urban environments. This review assesses the current state of the art of photocatalytic oxidation materials, designed for the abatement of nitrogen oxides (NOx) in the urban environment, and typically, but not exclusively based on titanium dioxide (TiO2). Field trials with existing commercial materials, such as paints, asphalt and concrete, in a range of environments including street canyons, car parks, tunnels, highways and open streets, are considered in-depth. Lab studies containing the most recent developments in the photocatalytic materials are also summarised, as well as studies investigating the impact of physical parameters on their efficiency. It is concluded that this technology may be useful as a part of the measures used to lower urban air pollution levels, yielding ∼2% NOx removal in the immediate area around the surface, for optimised TiO2, in some cases, but is not capable of the reported high NOx removal efficiencies >20% in outdoor urban environments, and can in some cases lower air quality by releasing hazardous by-products. However, research into new material is ongoing. The reason for the mixed results in the studies reviewed, and massive range of removal efficiencies reported (from negligible and up to >80%) is mainly the large range of testing practices used. Before deployment in individual environments site-specific testing should be performed, and new standards for lab and field testing should be developed. The longevity of the materials and their potential for producing hazardous by-products should also be considered.

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