scholarly journals Condensation sink of atmospheric vapors: the effect of vapor properties and the resulting uncertainties

2021 ◽  
Author(s):  
Santeri Tuovinen ◽  
Jenni Kontkanen ◽  
Runlong Cai ◽  
Markku Kulmala
Keyword(s):  
Human Health ◽  
Loss Rate ◽  
Aerosol Particles ◽  
Secondary Formation ◽  
Condensation Sink

Aerosol particles affect the climate and human health. Thus, understanding and accurately quantifying the processes associated with secondary formation of aerosol particles is highly important. The loss rate of vapor...

scholarly journals Particle number concentrations over Europe in 2030: the role of emissions and new particle formation

2013 ◽  
Vol 13 (20) ◽  
pp. 10271-10283 ◽  
Author(s):  
L. Ahlm ◽  
J. Julin ◽  
C. Fountoukis ◽  
S. N. Pandis ◽  
I. Riipinen
Keyword(s):  
Human Health ◽  
Particle Number ◽  
Aerosol Particles ◽  
Particle Formation ◽  
Number Concentration ◽  
Anthropogenic Emissions ◽  
Particle Number Concentration ◽  
New Particle Formation ◽  
So2 Emissions ◽  
Emission Reductions

Abstract. The aerosol particle number concentration is a key parameter when estimating impacts of aerosol particles on climate and human health. We use a three-dimensional chemical transport model with detailed microphysics, PMCAMx-UF, to simulate particle number concentrations over Europe in the year 2030, by applying emission scenarios for trace gases and primary aerosols. The scenarios are based on expected changes in anthropogenic emissions of sulfur dioxide, ammonia, nitrogen oxides, and primary aerosol particles with a diameter less than 2.5 μm (PM2.5) focusing on a photochemically active period, and the implications for other seasons are discussed. For the baseline scenario, which represents a best estimate of the evolution of anthropogenic emissions in Europe, PMCAMx-UF predicts that the total particle number concentration (Ntot) will decrease by 30–70% between 2008 and 2030. The number concentration of particles larger than 100 nm (N100), a proxy for cloud condensation nuclei (CCN) concentration, is predicted to decrease by 40–70% during the same period. The predicted decrease in Ntot is mainly a result of reduced new particle formation due to the expected reduction in SO2 emissions, whereas the predicted decrease in N100 is a result of both decreasing condensational growth and reduced primary aerosol emissions. For larger emission reductions, PMCAMx-UF predicts reductions of 60–80% in both Ntot and N100 over Europe. Sensitivity tests reveal that a reduction in SO2 emissions is far more efficient than any other emission reduction investigated, in reducing Ntot. For N100, emission reductions of both SO2 and PM2.5 contribute significantly to the reduced concentration, even though SO2 plays the dominant role once more. The impact of SO2 for both new particle formation and growth over Europe may be expected to be somewhat higher during the simulated period with high photochemical activity than during times of the year with less incoming solar radiation. The predicted reductions in both Ntot and N100 between 2008 and 2030 in this study will likely reduce both the aerosol direct and indirect effects, and limit the damaging effects of aerosol particles on human health in Europe.

scholarly journals The fate of NO<sub>x</sub> emissions due to nocturnal oxidation at high latitudes: 1-D simulations and sensitivity experiments

2014 ◽  
Vol 14 (14) ◽  
pp. 7601-7616 ◽  
Author(s):  
P. L. Joyce ◽  
R. von Glasow ◽  
W. R. Simpson
Keyword(s):  
Aerosol Particles ◽  
Urban Pollution ◽  
Model Parameters ◽  
Atmospheric Reactions ◽  
Dinitrogen Pentoxide ◽  
Sensitivity Experiments ◽  
Photolysis Rates ◽  
Secondary Formation ◽  
Fate Of Nitrogen ◽  
Significant Mass

Abstract. The fate of nitrogen oxide pollution during high-latitude winter is controlled by reactions of dinitrogen pentoxide (N2O5) and is highly affected by the competition between heterogeneous atmospheric reactions and deposition to the snowpack. MISTRA (MIcrophysical STRAtus), a 1-D photochemical model, simulated an urban pollution plume from Fairbanks, Alaska to investigate this competition of N2O5 reactions and explore sensitivity to model parameters. It was found that dry deposition of N2O5 made up a significant fraction of N2O5 loss near the snowpack, but reactions on aerosol particles dominated loss of N2O5 over the integrated atmospheric column. Sensitivity experiments found the fate of NOx emissions were most sensitive to NO emission flux, photolysis rates, and ambient temperature. The results indicate a strong sensitivity to urban area density, season and clouds, and temperature, implying a strong sensitivity of the results to urban planning and climate change. Results suggest that secondary formation of particulate (PM2.5) nitrate in the Fairbanks downtown area does not contribute significant mass to the total PM2.5 concentration, but appreciable amounts are formed downwind of downtown due to nocturnal NOx oxidation and subsequent reaction with ammonia on aerosol particles.

Regional air quality in Leipzig, Germany: detailed source apportionment of size-resolved aerosol particles and comparison with the year 2000

2016 ◽  
Vol 189 ◽  
pp. 291-315 ◽  
Author(s):  
D. van Pinxteren ◽  
K. W. Fomba ◽  
G. Spindler ◽  
K. Müller ◽  
L. Poulain ◽  
...  
Keyword(s):  
Source Apportionment ◽  
Coal Combustion ◽  
Elemental Carbon ◽  
Aerosol Particles ◽  
Biomass Combustion ◽  
Coarse Particles ◽  
Air Mass ◽  
Accumulation Mode ◽  
Secondary Formation ◽  
Year 2000

A detailed source apportionment of size-resolved aerosol particles in the area of Leipzig, Germany, was performed. Sampling took place at four sites (traffic, traffic/residential, urban background, regional background) in parallel during summer 2013 and the winters 2013/14/15. Twenty-one samples were taken per season with a 5-stage Berner impactor and analysed for particulate mass, inorganic ions, organic and elemental carbon, water-soluble organic carbon, trace metals, and a wide range of organic species. The compositional data were used to estimate source contributions to particulate matter (PM) in quasi-ultrafine (up to 140 nm), accumulation mode, and coarse size ranges using Positive Matrix Factorisation (PMF) receptor modelling. Traffic (exhaust and general traffic emissions), coal combustion, biomass combustion, photochemistry, general secondary formation, cooking, fungal spores, urban dust, fresh sea/road salt, and aged sea salt were all found to contribute to different extents to observed PM concentrations. PMF derived estimates agreed reasonably with estimates from established macrotracer approaches. Quasi-ultrafine PM originated mainly from traffic (20–50%) and photochemistry (30–50%) in summer, while it was dominated by solid fuel (mainly biomass) combustion in winter (50–70%). Tentatively identified cooking aerosol contributed up to 36% on average at the residential site. For accumulation mode particles, two secondary sources typically contributed 40–90% to particle mass. In winter, biomass and coal combustion contributions were up to ca. 25% and 45%, respectively. Main sources of coarse particles were diverse and included nearly all PMF-resolved ones depending on season and air mass origin. For PM10, traffic (typically 20–40% at kerbside sites), secondary formation (30–60%), biomass combustion (10–15% in winter), and coal combustion (30–40% in winter with eastern air mass inflow) were the main quantified sources. At the residential site, contributions from biomass combustion derived up to 60% from local emissions. Coal combustion as a significant source was only present during eastern air mass inflow and showed very similar concentrations at all sites, indicating the importance of trans-boundary air pollution transport in the study area. Overall, nearly half of the PM10 mass was attributed to urban sources by a simple subtractive approach with highest reduction potentials of up to 80% for local (urban) mitigation measures in ultrafine and coarse particles. Local increments of elemental carbon have decreased by about 50% as compared to the year 2000, corroborating results from a former study on the positive effects of a low emission zone, implemented in Leipzig in 2011.

Atmospheric gas-to-particle conversion: why NPF events are observed in megacities?

2017 ◽  
Vol 200 ◽  
pp. 271-288 ◽  
Author(s):  
M. Kulmala ◽  
V.-M. Kerminen ◽  
T. Petäjä ◽  
A. J. Ding ◽  
L. Wang
Keyword(s):  
Particle Number ◽  
Aerosol Particles ◽  
Particle Diameter ◽  
Conceptual Modelling ◽  
Cluster Growth ◽  
Direct Observations ◽  
Primary Emissions ◽  
Small Clusters ◽  
Condensation Sink ◽  
Key Parameter

In terms of the global aerosol particle number load, atmospheric new particle formation (NPF) dominates over primary emissions. The key for quantifying the importance of atmospheric NPF is to understand how gas-to-particle conversion (GTP) takes place at sizes below a few nanometers in particle diameter in different environments, and how this nano-GTP affects the survival of small clusters into larger sizes. The survival probability of growing clusters is tied closely to the competition between their growth and scavenging by pre-existing aerosol particles, and the key parameter in this respect is the ratio between the condensation sink (CS) and the cluster growth rate (GR). Here we define their ratio as a dimensionless survival parameter,P, asP= (CS/10−4s−1)/(GR/nm h−1). Theoretical arguments and observations in clean and moderately-polluted conditions indicate thatPneeds to be smaller than about 50 for a notable NPF to take place. However, the existing literature shows that in China, NPF occurs frequently in megacities such as in Beijing, Nanjing and Shanghai, and our analysis shows that the calculated values ofPare even larger than 200 in these cases. By combining direct observations and conceptual modelling, we explore the variability of the survival parameterPin different environments and probe the reasons for NPF occurrence under highly-polluted conditions.

scholarly journals The fate of NO<sub>x</sub> emissions due to nocturnal oxidation at high latitudes: 1-D simulations and sensitivity experiments

2014 ◽  
Vol 14 (6) ◽  
pp. 7385-7424
Author(s):  
P. L. Joyce ◽  
R. von Glasow ◽  
W. R. Simpson
Keyword(s):  
Aerosol Particles ◽  
Urban Pollution ◽  
Model Parameters ◽  
Atmospheric Reactions ◽  
Dinitrogen Pentoxide ◽  
Sensitivity Experiments ◽  
Photolysis Rates ◽  
Secondary Formation ◽  
Fate Of Nitrogen ◽  
Significant Mass

Abstract. The fate of nitrogen oxide pollution during high-latitude winter is controlled by reactions of dinitrogen pentoxide (N2O5) and is highly affected by the competition between heterogeneous atmospheric reactions and deposition to the snowpack. MISTRA, a 1-D photochemical model, simulated an urban pollution plume from Fairbanks, Alaska to investigate this competition of N2O5 reactions and explore sensitivity to model parameters. It was found that dry deposition of N2O5 made up a significant fraction of N2O5 loss near the snowpack, but reactions on aerosol particles dominated loss of N2O5 over the integrated atmospheric column. Sensitivity experiments found the fate of NOx emissions were most sensitive to NO emission flux, photolysis rates, and ambient temperature. The results indicate a strong sensitivity to urban area density, season and clouds, and temperature, implying a strong sensitivity of the results to urban planning and climate change. Results suggest that secondary formation of particulate (PM2.5) nitrate in the Fairbanks downtown area does not contribute significant mass to the total PM2.5 concentration, but appreciable amounts are formed downwind of downtown due to nocturnal NOx oxidation and subsequent reaction with ammonia on aerosol particles.

scholarly journals VARIATION OF OZONE AND AEROSOL PARTICLE NUMERICAL CONCENTRATIONS ON THE WORKING PREMISES UNDER DIFFERENT MICROCLIMATIC PARAMETERS/OZONO KONCENTRACIJOS IR AEROZOLIO DALELIŲ SKAITINĖS KONCENTRACIJOS DARBO PATALPOSE ESANT SKIRTINGIEMS APLINKOS RODIKLIAMS/ ИЗМЕНЕНИЕ КОНЦЕНТРАЦИИ ОЗОНА И СЧЕТНОЙ КОНЦЕНТРАЦИИ ЧАСТИЦ АЭРОЗОЛЯ В РАБОЧИX ПОМЕЩЕНИЯX ПРИ РАЗЛИЧНЫХ МИКРОКЛИМАТИЧЕСКИХ ПАРАМЕТРАХ

2008 ◽  
Vol 16 (3) ◽  
pp. 135-142 ◽  
Author(s):  
Vaida Valuntaitė ◽  
Raselė Girgždienė
Keyword(s):  
Relative Humidity ◽  
Temperature Gradient ◽  
Human Health ◽  
Ozone Concentration ◽  
Aerosol Particles ◽  
Laser Printer ◽  
Pollutant Emission ◽  
Work Intensity ◽  
Minimum Concentration ◽  
Copying Machine

Investigations of air quality on the working and residential premises as well as its effect on human health and materials have been started many years ago and are still intensively carried out now. This is a result of application of new materials in the field of construction, implementation of new technological processes as well as intensive use of various devices at home and workplaces. It is known that a high concentration of ozone and aerosols could have negative effects on human health as well as on materials. Quite frequently not quite new copying machines which might be a strong source of pollutant emission are used for copying. An experiment was carried out on the working premises with three operating copying machines and a laser printer. The changes and distribution of ozone concentration and numerical concentration of aerosol particles (d > 0.4 μm) from the source of emission, i. e. a copying machine, were investigated. Measurements were carried out under different conditions of copying work intensity and ventilation. The microclimate parameters (temperature gradients, noise level, relative humidity, light) and spectrum of aerosol particles (0.4–2.0 μm) were measured as well. A copying machine was found to be the main source of ozone and aerosol particles. Intensity of copying work largely determined dynamics of these pollutants on the office premises. The maximum ozone concentration and minimum concentration of aerosol particles were estimated during automatic copying. It was found that ozone concentrations outside could not be the main and significant source of this pollutant in the room. Positive relationship between ozone concentration and temperature gradient was found; the correlation coefficient was 0.85, and the negative one (‐0.81) was between aerosol particles and temperature gradient. During experiment it was found that the pollutants under examination were mostly influenced by relative humidity and temperature gradient. Santrauka Darbo ir gyvenamųjų patalpų oro kokybės, jo poveikio žmogaus sveikatai ir medžiagoms tyrimai, pradėti pasaulyje prieš daugelį metų, yra intensyviai tęsiami ir dabar. Tai yra susiję su naujų medžiagų naudojimu statybose, naujų technologinių procesų diegimu ir intensyviu įvairių prietaisų naudojimu buityje ir darbo vietose. Žinoma, kad didelės ozono ir aerozolių koncentracijos gali pakenkti žmonių sveikatai, turėti neigiamos įtakos medžiagoms. Gana dažnai yra naudojami ne visai nauji kopijavimo aparatai, kurie gali būti stiprūs teršalų emisijos šaltiniai. Eksperimentas buvo atliekamas darbo patalpoje, kurioje veikė trys kopijavimo aparatai ir lazerinis spausdintuvas. Buvo tiriama ozono koncentracijos ir aerozolio dalelių (d > 0,4 µm) skaitinės koncentracijos pokyčiai, jų sklaida nuo emisijos šaltinio – kopijavimo aparato. Matavimai atlikti esant skirtingam kopijavimo intensyvumui ir skirtingoms ventiliacijos sąlygoms. Lygiagrečiai matuoti aplinkos rodikliai (temperatūros gradientas, triukšmo lygis, santykinė drėgmė, apšvietimas) ir aerozolio dalelių (0,4–2,0 µm) spektras. Nustatyta, kad pagrindinis ozono ir aerozolio dalelių šaltinis buvo kopijavimo aparatas. Didelės įtakos šių teršalų dinamikai biuro patalpose turėjo kopijavimo intensyvumas. Didžiausia ozono ir mažiausia aerozolio dalelių koncentracija nustatyta esant automatiniam kopijavimui. Kopijavimo aparatų darbo metu patalpoje nustatyta vidutinė ozono koncentracija 60 µg/m³, o aerozolio dalelių – 78 · 106 vnt/m³. Nustatyta, kad ozono koncentracijos lauke negalėjo būti pagrindinis arba svarbus šio teršalo patalpoje šaltinis. Automatinio kopijavimo metu nustatyta maksimali vidutinė ozono koncentracija 166 µg/m³. Nustatytas teigiamas ryšys tarp ozono koncentracijos ir temperatūros gradiento, koreliacijos koeficientas – 0,85, tačiau tarp aerozolio dalelių ir temperatūros gradiento gautas neigiamas koreliacijos koeficientas (–0,81). Darbo patalpoje labiausiai kito 0,4–0,5 µm aerozolio dalelės, o didesnių kaip 1,5 µm dalelių kiekis buvo mažiausias. Tiriant aplinkos rodiklių poveikį ozono ir aerozolio dalelių sklaidai patalpoje gauta, kad tiriamiems teršalams didžiausios įtakos turėjo santykinė drėgmė ir temperatūros gradientas. Резюме Исследования качества воздуха рабочих и жилых помещений, а также влияния воздуха на здоровье человека и материалы, издавна проводившиеся в различных странах мира, интенсивно проводятся и в настоящее время. Это связано с использованием новых материалов в строительстве, внедрением новых технологических процессов и интенсивным использованием различных приборов в быту и на рабочих местах. Известно, что большая концентрация озона и аэрозолей может наносить вред здоровью людей и оказывать отрицательное воздействие на материалы. Зачастую для копирования используются не новые копировальные аппараты, которые могут являться сильными источниками эмиссии загрязнений. Эксперимент проводился в рабочем помещении, в котором работали три копировальных аппарата и лазерный принтер. Исследовалось изменение концентрации озона и счетной концентрации аэрозольных частиц (d > 0,4 мкм), а также его рассеяния от источника эмиссии – копировального аппарата. Измерения проводились при разной интенсивности копирования и разных условиях вентиляции. Параллельно проводились измерения параметров окружающей среды (градиент температуры, уровень шума, относительная влажность, освещение) и спектра аэрозольных частиц (0,4–2,0 мкм). Установлено, что основным источником озона и аэрозольных частиц являлся копировальный аппарат. Интенсивность копирования в большей части обусловила динамику этих загрязнений в офисном помещении. Наибольшая концентрация озона и наименьшая концентрация аэрозольных частиц установлена при автоматическом копировании. Во время работы копировальных аппаратов в рабочем помещении установлена средняя концентрация озона – 60 мкг/м³, а аэрозольных частиц – 78·106 ед./м³. Установлено, что концентрация озона вне помещения не могла быть основным либо важным источником загрязнения в помещении. Во время автоматического копирования установлена максимальная средняя концентрация озона – 166 мкг/м³. Установлена положительная связь между концентрацией озона и градиентом температуры, коэффициент корреляции составил 0,85, однако между аэрозольными частицами и градиентом температуры получен отрицательный коэффициент корреляции (–0,81). В рабочем помещении наибольшим изменениям подверглись аэрозольные частицы размером 0,4–0,5 мкм, а количество частиц размером свыше 0,5 мкм было наименьшим. При исследовании воздействия параметров среды на рассеяние озона и аэрозольных частиц установлено, что наибольшее влияние на исследуемое загрязнение оказывали относительная влажность и градиент температуры

scholarly journals Particle number concentrations over Europe in 2030: the role of emissions and new particle formation

2013 ◽  
Vol 13 (4) ◽  
pp. 8769-8803
Author(s):  
L. Ahlm ◽  
J. Julin ◽  
C. Fountoukis ◽  
S. N. Pandis ◽  
I. Riipinen
Keyword(s):  
Human Health ◽  
Particle Number ◽  
Aerosol Particles ◽  
Particle Formation ◽  
Number Concentration ◽  
Anthropogenic Emissions ◽  
Particle Number Concentration ◽  
New Particle Formation ◽  
So2 Emissions ◽  
Emission Reductions

Abstract. The aerosol particle number concentration is a key parameter when estimating impacts of aerosol particles on climate and human health. We use a three-dimensional chemical transport model with detailed microphysics, PMCAMx-UF, to simulate particle number concentrations over Europe in the year 2030, by applying emission scenarios for trace gases and primary aerosols. The scenarios are based on expected changes in anthropogenic emissions of sulphur dioxide, ammonia, nitrogen oxides, and primary aerosol particles with a diameter less than 2.5 μm (PM2.5) focusing on a photochemically active period. For the baseline scenario, which represents a best estimate of the evolution of anthropogenic emissions in Europe, PMCAMx-UF predicts that the total particle number concentration (Ntot) will decrease by 30–70% between 2008 and 2030. The number concentration of particles larger than 100 nm (N100), a proxy for cloud condensation nuclei (CCN) concentration, is predicted to decrease by 40–70% during the same period. The predicted decrease in Ntot is mainly a result of reduced new particle formation due to the expected reduction in SO2 emissions, whereas the predicted decrease in N100 is a result of both decreasing condensational growth and reduced primary aerosol emissions. For larger emission reductions, PMCAMx-UF predicts reductions of 60–80% in both Ntot and N100 over Europe. Sensitivity tests reveal that a reduction in SO2 emissions is far more efficient than any other emission reduction investigated, in reducing Ntot. For N100, emission reductions of both SO2 and PM2.5 contribute significantly to the reduced concentration, even though SO2 plays the dominant role once more. The impact of SO2 for both new particle formation and growth over Europe may be expected to be somewhat higher during the simulated period with high photochemical activity than during times of the year with less incoming solar radiation. The predicted reductions in both Ntot and N100 between 2008 and 2030 in this study will likely reduce both the aerosol direct and indirect effects, and limit the damaging effects of aerosol particles on human health in Europe.

scholarly journals Significant alteration in the hygroscopic properties of urban aerosol particles by the secondary formation of organics

2008 ◽  
Vol 35 (2) ◽  
Author(s):  
Michihiro Mochida ◽  
Takuma Miyakawa ◽  
Nobuyuki Takegawa ◽  
Yu Morino ◽  
Kimitaka Kawamura ◽  
...  
Keyword(s):  
Aerosol Particles ◽  
Significant Alteration ◽  
Urban Aerosol ◽  
Hygroscopic Properties ◽  
Secondary Formation

Lycopene alleviates sulfamethoxazole-induced hepatotoxicity in grass carp (Ctenopharyngodon idellus) via suppression of oxidative stress, inflammation and apoptosis

2020 ◽  
Vol 11 (10) ◽  
pp. 8547-8559
Author(s):  
Hongjing Zhao ◽  
Yu Wang ◽  
Mengyao Mu ◽  
Menghao Guo ◽  
Hongxian Yu ◽  
...  
Keyword(s):  
Oxidative Stress ◽  
Secondary Metabolites ◽  
Human Health ◽  
Grass Carp ◽  
Aquatic Environment ◽  
Ctenopharyngodon Idellus

Antibiotics are used worldwide to treat diseases in humans and other animals; most of them and their secondary metabolites are discharged into the aquatic environment, posing a serious threat to human health.

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