scholarly journals Role of ammonia in European air quality with changing land and ship emissions between 1990 and 2030

2020 ◽  
Vol 20 (24) ◽  
pp. 15665-15680
Author(s):  
Sebnem Aksoyoglu ◽  
Jianhui Jiang ◽  
Giancarlo Ciarelli ◽  
Urs Baltensperger ◽  
André S. H. Prévôt
Keyword(s):  
Air Quality ◽  
Transition Period ◽  
Transport Model ◽  
The Other ◽  
Aerosol Formation ◽  
So2 Emissions ◽  
Ship Emissions ◽  
The Future ◽  
The Mediterranean

Abstract. The focus of this modeling study is on the role of ammonia in European air quality in the past as well as in the future. Ammonia emissions have not decreased as much as the other secondary inorganic aerosol (SIA) precursors – nitrogen oxides (NOx) and sulfur dioxide (SO2) – since the 1990s and are still posing problems for air quality and the environment. In this study, air quality simulations were performed with a regional chemical transport model at decadal intervals between 1990 and 2030 to understand the changes in the chemical species associated with SIA under varying land and ship emissions. We analyzed the changes in air concentrations of ammonia, nitric acid, ammonium, particulate nitrate and sulfate as well as changes in the dry and wet deposition of ammonia and ammonium. The results show that the approximately 40 % decrease in SIA concentrations between 1990 and 2010 was mainly due to reductions in NOx and SO2 emissions. The ammonia concentrations on the other hand decreased only near the high-emission areas such as the Netherlands and northern Italy by about 30 %, while there was a slight increase in other parts of Europe. Larger changes in concentrations occurred mostly during the first period (1990–2000). The model results indicate a transition period after 2000 for the composition of secondary inorganic aerosols due to a larger decrease in sulfate concentrations than nitrate. Changes between 2010 and 2030 – assuming the current legislation (CLE) scenario – are predicted to be smaller than those achieved earlier for all species analyzed in this study. The scenario simulations suggest that if ship emissions will be regulated more strictly in the future, SIA formation will decrease especially around the Benelux area, North Sea, Baltic Sea, English Channel and the Mediterranean region, leaving more ammonia in the gas phase, which would lead to an increase in dry deposition. In the north of the domain, the decrease in SIA would be mainly due to reduced formation of particulate nitrate, while the change around the Mediterranean would be caused mainly by decreased sulfate aerosol concentrations. One should also keep in mind that potentially higher temperatures in the future might increase the evaporation of ammonium nitrate to form its gaseous components NH3 and HNO3. Sensitivity tests with reduced NOx and NH3 emissions indicate a shift in the sensitivity of aerosol formation from NH3 towards NOx emissions between 1990 and 2030 in most of Europe except the eastern part of the model domain.

scholarly journals Role of ammonia in European air quality with changing land and ship emissions between 1990 and 2030

2020 ◽  
Author(s):  
Sebnem Aksoyoglu ◽  
Jianhui Jiang ◽  
Giancarlo Ciarelli ◽  
Urs Baltensperger ◽  
André S. H. Prévôt
Keyword(s):  
Air Quality ◽  
Transition Period ◽  
Transport Model ◽  
The Other ◽  
Aerosol Formation ◽  
So2 Emissions ◽  
Ship Emissions ◽  
The Future ◽  
The Mediterranean

Abstract. The focus of this modeling study is on the role of ammonia in European air quality in the past as well as in the future. Ammonia emissions have not decreased as much as the other secondary inorganic aerosol (SIA) precursors nitrogen oxides (NOx) and sulfur dioxide (SO2) since 1990s, and are still posing problems for air quality and the environment. In this study, air quality simulations were performed with a regional chemical transport model at decadal intervals between 1990 and 2030 to understand the changes in the chemical species associated with SIA under varying land and ship emissions. We analyzed the changes in air concentrations of ammonia, nitric acid, ammonium, particulate nitrate and sulfate as well as changes in the dry and wet deposition of ammonia and ammonium. The results show that the approximately 40 % decrease in SIA concentrations between 1990 and 2010 was mainly due to reductions of NOx and SO2 emissions. The ammonia concentrations on the other hand decreased only near the high emission areas such as the Netherlands and northern Italy by about 30 % while there was a slight increase in other parts of Europe. Larger changes in concentrations occurred mostly during the first period (1990–2000). The model results indicate a transition period after 2000 for the composition of secondary inorganic aerosols due to a larger decrease in sulfate concentrations than nitrate. Changes between 2010 and 2030 – assuming the current legislation (CLE) scenario – are predicted to be smaller than those achieved earlier for all species analyzed in this study. The scenario simulations suggest that if ship emissions will be regulated more strictly in the future, SIA formation will decrease especially around the Benelux area, North Sea, Baltic Sea, English Channel and the Mediterranean region, leaving more ammonia in the gas phase which would lead to an increase in dry deposition. In the North, the decrease in SIA would be mainly due to reduced formation of particulate nitrate while the change around the Mediterranean would be caused mainly by decreased sulfate aerosol concentrations. Sensitivity tests with reduced NOx and NH3 emissions indicate a shift in the sensitivity of aerosol formation from NH3 towards NOx emissions between 1990 and 2030 in most of Europe except the eastern part of the model domain.

On the role of the dispute between "non-possessors" and "Josephites" in the culture of Moscow's prediction

1998 ◽  
pp. 61-62
Author(s):  
N. S. Jurtueva
Keyword(s):  
The Other ◽  
Moral Transformation ◽  
15Th Century ◽  
The Future ◽  
Secular Power

In the XIV century. centripetal tendencies began to appear in the Moscow principality. Inside the Russian church, several areas were distinguished. Part of the clergy supported the specificobar form. The other understood the need for transformations in society. As a result, this led to a split in the Russian church in the 15th century for "non-possessors" and "Josephites". The former linked the fate of the future with the ideology of hesychasm and its moral transformation, while the latter sought support in alliance with a strong secular power.

scholarly journals Development of the city-scale chemistry transport model CityChem-EPISODE and its application to the city of Hamburg

2018 ◽  
Author(s):  
Matthias Karl
Keyword(s):  
Air Quality ◽  
Urban Area ◽  
Transport Model ◽  
Dispersion Model ◽  
Temporal Correlation ◽  
Urban Atmosphere ◽  
Aerosol Formation ◽  
Urban Background ◽  
New Model ◽  
The City

Abstract. This paper describes the City-scale Chemistry (CityChem) extension of the urban dispersion model EPISODE with the aim to enable chemistry/transport simulations of multiple reactive pollutants on urban scales. The new model is called CityChem-EPISODE. The primary focus is on the simulation of urban ozone concentrations. Ozone is produced in photochemical reaction cycles involving nitrogen oxides (NOx) and volatile organic compounds (VOC) emitted by various anthropogenic activities in the urban area. The performance of the new model was evaluated with a series of synthetic tests and with a first application to the air quality situation in the city of Hamburg, Germany. The model performs fairly well for ozone in terms of temporal correlation and bias at the air quality monitoring stations in Hamburg. In summer afternoons, when photochemical activity is highest, modelled median ozone at an inner-city urban background station was about 30 % lower than the observed median ozone. Inaccuracy of the computed photolysis frequency of nitrogen dioxide (NO2) is the most probable explanation for this. CityChem-EPISODE reproduces the spatial variation of annual mean NO2 concentrations between urban background, traffic and industrial stations. However, the temporal correlation between modelled and observed hourly NO2 concentrations is weak for some of the stations. For daily mean PM10, the performance of CityChem-EPISODE is moderate due to low temporal correlation. The low correlation is linked to uncertainties in the seasonal cycle of the anthropogenic particulate matter (PM) emissions within the urban area. Missing emissions from domestic heating might be an explanation for the too low modelled PM10 in winter months. Four areas of need for improvement have been identified: (1) dry and wet deposition fluxes; (2) treatment of photochemistry in the urban atmosphere; (3) formation of secondary inorganic aerosol (SIA); and (4) formation of biogenic and anthropogenic secondary organic aerosol (SOA). The inclusion of secondary aerosol formation will allow for a better sectorial attribution of observed PM levels. Envisaged applications of the CityChem-EPISODE model are urban air quality studies, environmental impact assessment, sensitivity analysis of sector-specific emission and the assessment of local and regional emission abatement policy options.

scholarly journals A new diagnostic for tropospheric ozone production

2017 ◽  
Author(s):  
Peter M. Edwards ◽  
Mathew J. Evans
Keyword(s):  
Air Quality ◽  
Tropospheric Ozone ◽  
Transport Model ◽  
Chemical Transport ◽  
Ozone Production ◽  
Chemical Transport Model ◽  
Organic Species ◽  
Earth’S Climate ◽  
Oxidation Of Organics

Abstract. Tropospheric ozone is important for the Earth’s climate and air quality. It is produced during the oxidation of organics in the presence of nitrogen oxides. Due to the range of organic species emitted and the chain like nature of their oxidation, this chemistry is complex and understanding the role of different processes (emission, deposition, chemistry) is difficult. We demonstrate a new methodology for diagnosing ozone production based on the processing of bonds contained within emitted molecules, the fate of which is determined by the conservation of spin of the bonding electrons. Using this methodology to diagnose ozone production in the GEOS-Chem chemical transport model, we demonstrate its advantages over the standard diagnostic. We show that the number of bonds emitted, their chemistry and lifetime, and feedbacks on OH are all important in determining the ozone production within the model and its sensitivity to changes. This insight may allow future model-model comparisons to better identify the root causes of model differences.

scholarly journals Bestuursetiek in bestuursopleiding: Retoriek of realiteit

1993 ◽  
Vol 19 (3) ◽  
Author(s):  
S. Kruger
Keyword(s):  
Business Ethics ◽  
The Other ◽  
Literature Study ◽  
Business Training ◽  
Other Hand ◽  
The Future ◽  
The Subject ◽  
The One ◽  
Insight Into

Business ethics in business training: Oratory or the actuality. This article is the culmination of an in-depth literature study. On the one hand an attempt is made to incorporate the views of different authors, while on the other hand an attempt is made to take part in the debate which is initiated by the current renewal of interest in the subject Business Ethics. Within this framework attention is paid to the question of whether business ethics can be taught and if so, to what extent it's influence will be felt. Secondly, an insight into the teaching of business ethics in the future is provided. Within this context the approach to the teaching, the content, the role of the student and the responsibility of the educator in particular are addressed. Opsomming Hierdie artikel is die resultaat van 'n indringende literatuurstudie. Daar word gepoog om enersyds verskillende skrywers se standpunte saam te vat, maar andersyds ook kritiese kommentaar te lower en deel te neem aan die debat wat deur die huidige opiewing in die belangstelling in Bestuursetiek bestaan. Binne die raamwerk sal aandag aan die volgende geskenk word: Die beantwoording van die vraag of Bestuursetiek onderrig kan word en indien wel die trefwydte daarvan. Tweedens 'n toekomsblik op die onderrig van Bestuursetiek. Binne die konteks word die benadering tot die onderrig/ die inhoud en die rol van die student en die verantwoordelikheid van die dosent bekvk.

scholarly journals Heterogeneous sulfate aerosol formation mechanisms during wintertime Chinese haze events: Air quality model assessment using observations of sulfate oxygen isotopes in Beijing

2019 ◽  
Author(s):  
Jingyuan Shao ◽  
Qianjie Chen ◽  
Yuxuan Wang ◽  
Xiao Lu ◽  
Pengzhen He ◽  
...  
Keyword(s):  
Air Quality ◽  
Oxygen Isotopes ◽  
Metal Ion ◽  
Transport Model ◽  
Formation Mechanisms ◽  
Model Assessment ◽  
Aerosol Formation ◽  
Air Quality Model ◽  
Sulfate Production ◽  
Sulfate Formation

Abstract. Air quality models have not been able to reproduce the magnitude of the observed concentrations of fine particulate matter (PM2.5) during wintertime Chinese haze events. The discrepancy has been at least partly attributed to low biases in modeled sulfate production rates due to the lack of heterogeneous sulfate production on aerosols in the models. In this study, we explicitly implement four heterogeneous sulfate formation mechanisms into a regional chemical transport model, in addition to gas-phase and in-cloud sulfate production. We compare the model results with observations of sulfate concentrations and oxygen isotopes (Δ17O(SO42−)) in the winter of 2014–2015, the latter of which is highly sensitive to the relative importance of different sulfate production mechanisms. Model results suggest that heterogeneous sulfate production on aerosols accounts for about 20 % of sulfate production in clean and polluted conditions, partially reducing the modeled low bias in sulfate concentrations. Model sensitivity studies in comparison with the Δ17O(SO42−) observations suggest that heterogeneous sulfate formation is dominated by transition metal ion catalyzed oxidation of SO2.

scholarly journals Effects of ship emissions on air quality in the Baltic Sea region simulated with three different chemistry transport models

2019 ◽  
Author(s):  
Matthias Karl ◽  
Jan Eiof Jonson ◽  
Andreas Uppstu ◽  
Armin Aulinger ◽  
Marja Prank ◽  
...  
Keyword(s):  
Air Quality ◽  
Boundary Conditions ◽  
Baltic Sea ◽  
The Other ◽  
Aerosol Formation ◽  
The Baltic Sea ◽  
Transport Models ◽  
Ship Traffic ◽  
Baltic Sea Region ◽  
The Baltic

Abstract. The Baltic Sea is highly frequented shipping area with busy shipping lanes close to densely populated regions. Exhaust emissions from ship traffic into the atmosphere are not only enhancing air pollution, they also affect the Baltic Sea environment through acidification and eutrophication of marine waters and surrounding terrestrial ecosystems. As part of the European BONUS project SHEBA (Sustainable Shipping and Environment of the Baltic Sea Region), the transport, chemical transformation and fate of atmospheric pollutants in the Baltic Sea region was simulated with three regional chemistry transport models (CTM) systems, CMAQ, EMEP/MSC-W and SILAM with grid resolutions between 4 km and 11 km. The main goal was to quantify the effect that shipping emissions have on the regional air quality in the Baltic Sea region when the same shipping emissions dataset but different CTMs in their typical setups are used. The performance of these models and the shipping contribution to the results of the individual models was evaluated for sulphur dioxide (SO2), nitrogen dioxide (NO2) and ozone (O3) and particulate matter (PM2.5). Model results from the three CTMs were compared to observations from rural and urban background stations of the AirBase monitoring network in the coastal areas of the Baltic Sea region. The performance of the three CTM systems to predict pollutant concentrations is similar. However, observed PM2.5 in summer was underestimated strongly by CMAQ and to some extent by EMEP/MSC-W. The spatial average of annual mean O3 in the EMEP/MSC-W simulation is 15–25 % higher compared to the other two simulations, which is mainly the consequence of using a different set of boundary conditions for the European model domain. There are significant differences in the calculated ship contributions to the levels of air pollutants among the three models. SILAM predicted a much weaker ozone depletion through NO emissions in the proximity of the main shipping routes than the other two models. In the entire Baltic Sea region the average contribution of ships to PM2.5 levels is in the range of 4.3–6.5 % for the three CTMs. Differences in ship-related PM2.5 between the models are mainly attributed to differences in the schemes for inorganic aerosol formation. Inspection of the ship-related elemental carbon (EC) revealed that assumptions about the vertical ship emission profile can affect the dispersion and abundance of ship-related pollutants in the near-ground atmosphere. The models are in agreement regarding the ship-related deposition of oxidised nitrogen, reporting a ship contribution in the range of 21–23 ktN y−1 as atmospheric input to the Baltic Sea. Results from the present study show the sensitivity of the ship contribution to combined uncertainties of boundary conditions, meteorological data and aerosol formation and deposition schemes. This is an important step towards a more reliable evaluation of policy options regarding emission regulations for ship traffic and the planned introduction of a nitrogen emission control area (NECA) in the Baltic Sea and the North Sea in 2021.

scholarly journals The imaginary constitution of financial crises

2020 ◽  
Vol 68 (5) ◽  
pp. 932-947 ◽  
Author(s):  
Aris Komporozos-Athanasiou ◽  
Marianna Fotaki
Keyword(s):  
Financial Institutions ◽  
Financial Crises ◽  
Sociological Imagination ◽  
The Other ◽  
Other Hand ◽  
The Future ◽  
Cornelius Castoriadis ◽  
Social Visions ◽  
The One

This article proposes an alternative sociological framework for dealing with the imaginary constitution of financial crises. Theorisation of financial crises is often limited by dualistic juxtaposition of the rational and irrational, moral and immoral, calculative and intuitive, thus neglecting the imaginary structuring of such dyads in the construction of financial and fiscal realities. To address this lacuna, we introduce ideas from philosopher Cornelius Castoriadis, and develop a framework that unpicks the often-suppressed, mediating and generative role of imagination in finance. On the one hand, we show how dominant forms of imagination enable the financialisation of contemporary societies, serving to sustain existing debt practices and lender–debtor relationships. On the other hand, we propose a re-animated ‘sociological imagination’ that offers potential avenues for establishing alternative social visions of the future that will enable re-thinking of the nature of debt, money and financial institutions.

The Role of the Learned Man in Government

1958 ◽  
Vol 20 (3) ◽  
pp. 275-288 ◽  
Author(s):  
Paul H. Nitze
Keyword(s):  
Western Culture ◽  
The Other ◽  
The Past ◽  
Other Hand ◽  
The Future ◽  
The One

In the context of government, what do we mean by the phrase “a learned man”?* I take it we can mean a variety of things. On the one hand, we can have in mind the specialist, the expert, the man with an intensive and specialized background in a particular field of knowledge. On the other hand, we can have in mind the man with general wisdom, with that feeling for the past and the future which enriches a sense for the present, and with that appreciation for wider loyalties which deepens patriotism to one's country and finds bonds between it and Western culture and links with the universal aspirations of mankind.

scholarly journals Response of acid mobilization of iron-containing mineral dust to improvement of air quality projected in the future

2013 ◽  
Vol 13 (10) ◽  
pp. 28173-28223 ◽  
Author(s):  
A. Ito ◽  
L. Xu
Keyword(s):  
Air Quality ◽  
Environmental Changes ◽  
Transport Model ◽  
Mineral Dust ◽  
Chemical Transport Model ◽  
Iron Solubility ◽  
The Future ◽  
Northeastern Pacific ◽  
Combustion Aerosols ◽  
Quantitative Understanding

Abstract. Acidification of dust aerosols may increase aerosol iron (Fe) solubility, which is linked to mineral properties. Combustion aerosols can also elevate aerosol iron solubility when aerosol loading is low. Here, we use an atmospheric chemical transport model to investigate the deposition of filterable iron and its response to changes in anthropogenic emissions of both combustion aerosols and precursor gases. By introducing three classes of iron-containing minerals into the detailed aerosol chemistry model, we provide a theoretical examination of the effects of different dissolution behaviors on the acid mobilization of iron. Comparisons of modeled Fe dissolution curves with the measured dissolution rates for African (Tibesti) and Asian (Beijing) dust samples show overall good agreement under acidic conditions. The improved treatment of Fe in mineral dust and its dissolution scheme results in reasonable predictive capability for iron solubility over the oceans in the Northern Hemisphere. Our model results suggest that the improvement of air quality projected in the future will lead to a decrease of the filterable iron deposition from iron-containing mineral dust to the northeastern Pacific due to less acidification in Asian dust, which is mainly associated with the reduction of nitrogen oxides (NOx) emissions. These results could have important implications for iron fertilization of phytoplankton growth, and highlight the necessity of improving the process-based quantitative understanding of the response of the chemical modification in iron-containing minerals to environmental changes.

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