Ammonia emissions in Europe, part I: Development of a dynamical ammonia emission inventory

Nitrogen input from agricultural ammonia emissions into the environment causes numerous environmental and health problems. The purpose of this study is to present and evaluate an improved ammonia emission inventory based on a dynamical temporal parameterization suitable to compare and assess ammonia abatement strategies. The setup of the dynamical time profile (DTP) consists of individual temporal profiles for ammonia emissions, calculated for each model grid cell, depending on temperature, crop type, fertilizer and manure application, as well as on local legislation. It is based on the method of Skjøth et al., 2004 and Gyldenkærne et al., 2005. The method has been modified to cover the study area and to improve the performance of the emission model. To compare the results of the dynamical approach with the results of the static time profile (STP) the ammonia emission parameterizations have been implemented in the SMOKE for Europe emission model. Furthermore, the influence on secondary aerosol formation in the North Sea region and possible changes triggered through the use of a modified temporal distribution of ammonia emissions were analysed with the CMAQ chemistry transport model. The results were evaluated with observations of the European Monitoring and Evaluation Programme (EMEP). The correlation coefficient of NH3 improved significantly for 12 out of 16 EMEP measurement stations and an improvement in predicting the Normalized Mean Error can be seen for particulate NH4+ and NO3−. The prediction of the 95th percentile of the daily average concentrations has improved for NH3, NH4+ and NO3−. The NH3 concentration modelled with the STP is 157% higher in winter, and about 22% lower in early summer than the one modelled with the new DTP. Consequently, the influence of the DTP on the formation of secondary aerosols is particularly noticeable in winter, when the PM2.5 concentration is 25% lower in comparison to the use of STP for temporal disaggregation. Besides, the formation of particulate SO42− is not influenced by the use of the DTP

The ash dispersion over Europe during the Eyjafjallajökull eruption e Comparison of CMAQ simulations to remote sensing and air-borne in-situ observations

The dispersion of volcanic ash over Europe after the outbreak of the Eyjafjallajökull on Iceland on 14 April 2010 has been simulated with a conventional three-dimensional Eulerian chemistry transport model system, the Community Multiscale Air Quality (CMAQ) model. Four different emission scenarios representing the lower and upper bounds of the emission height and intensity were considered. The atmospheric ash concentrations turned out to be highly variable in time and space. The model results were compared to three different kinds of observations: Aeronet aerosol optical depth (AOD) measurements, Earlinet aerosol extinction profiles and in-situ observations of the ash concentration by means of optical particle counters aboard the DLR Falcon aircraft. The model was able to reproduce observed AOD values and atmospheric ash concentrations. Best agreement was achieved for lower emission heights and a fraction of 2% transportable ash in the total volcanic emissions. The complex vertical structure of the volcanic ash layers in the free troposphere could not be simulated. Compared to the observations, the model tends to show vertically more extended, homogeneous aerosol layers. This is caused by a poor vertical resolution of the model at higher altitudes and a lack of information about the vertical distribution of the volcanic emissions. Only a combination of quickly available observations of the volcanic ash cloud and atmospheric transport models can give a comprehensive picture of ash concentrations in the atmosphere

Ammonia emissions in Europe, part II: How ammonia emission abatement strategies affect secondary aerosols

In central Europe, ammonium sulphate and ammonium nitrate make up a large fraction of fine particles which pose a threat to human health. Most studies on air pollution through particulate matter investigate the influence of emission reductions of sulphur- and nitrogen oxides on aerosol concentration. Here, we focus on the influence of ammonia (NH3) emissions. Emission scenarios have been created on the basis of the improved ammonia emission parameterization implemented in the SMOKE for Europe and CMAQ model systems described in part I of this study. This includes emissions based on future European legislation (the National Emission Ceilings) as well as a dynamic evaluation of the influence of different agricultural sectors (e.g. animal husbandry) on particle formation. The study compares the concentrations of NH3, View the MathML sourceNH4+, NO3 -, sulphur compounds and the total concentration of particles in winter and summer for a political-, technical- and behavioural scenario. It was found that a reduction of ammonia emissions by 50% lead to a 24% reduction of the total PM2.5 concentrations in northwest Europe. The observed reduction was mainly driven by reduced formation of ammonium nitrate. Moreover, emission reductions during winter had a larger impact than during the rest of the year. This leads to the conclusion that a reduction of the ammonia emissions from the agricultural sector related to animal husbandry could be more efficient than the reduction from other sectors due to its larger share in winter ammonia emissions

Effect of exopolysaccharide from Ganoderma applanatum on the electrical properties of mouse fibroblast cells line L929 culture using an electric cell-substrate impedance sensing (ECIS) – Preliminary study

Introduction In recent years there has been intensified research on medicinal preparations of fungal origin. Some fungal polysaccharides may directly affect the inhibition of cancer cells proliferation which, stopping the cell cycle, leads to apoptosis. One of these substances (component of extract of Ganoderma spp) is extensively tested for its anti-cancer properties on the tumor cell lines. Electric cell-substrate impedance sensing (ECIS) is an in vitro impedance measuring system using alternating current (AC) to determinate the behaviour of the cells in physiological conditions. Objective The aim of the study was to examine the electric properties (resistance, capacitance and impedance) of mouse fibroblasts cell line L929 after treatment by different concentration of crude exopolysaccharides from Ganoderma applanatum (GpEPS) in real time by ECIS technique. Material and Methods For the study, the L929 cell line culture was treated by different concentrations of GpEPS: C1=228.5 µg/mL; C2=22.85 µg/mL; C3=2.285 µg/mL; C4=0.2285 µg/mL; and C5=0.02285 µg/mL. Default optimal frequencies were used: Resistance (R) 4000Hz, Impedance (Z) 16000Hz, Capacitance (C) 64000Hz. Results The study demonstrated that GpEPS had no significant effect on the resistance, capacitance and impedance cells cultures, which implies that there is no significant effect on the physiological processes of L929 fibroblasts. This indicates the possibility of using GpEPS preparation in anti-cancer therapy. Conclusions In the future, following further studies (comprising in preventive and therapeutic actions), GpEPS can be safely used in anti-cancer therapy which does not cause side-effects or damage to healthy cells

Effect of exopolysaccharide from Ganoderma applanatum on the electrical properties of mouse fibroblast cells line L929 culture using an electric cell-substrate impedance sensing (ECIS) – Preliminary study

Introduction In recent years there has been intensified research on medicinal preparations of fungal origin. Some fungal polysaccharides may directly affect the inhibition of cancer cells proliferation which, stopping the cell cycle, leads to apoptosis. One of these substances (component of extract of Ganoderma spp) is extensively tested for its anti-cancer properties on the tumor cell lines. Electric cell-substrate impedance sensing (ECIS) is an in vitro impedance measuring system using alternating current (AC) to determinate the behaviour of the cells in physiological conditions. Objective The aim of the study was to examine the electric properties (resistance, capacitance and impedance) of mouse fibroblasts cell line L929 after treatment by different concentration of crude exopolysaccharides from Ganoderma applanatum (GpEPS) in real time by ECIS technique. Material and Methods For the study, the L929 cell line culture was treated by different concentrations of GpEPS: C1=228.5 µg/mL; C2=22.85 µg/mL; C3=2.285 µg/mL; C4=0.2285 µg/mL; and C5=0.02285 µg/mL. Default optimal frequencies were used: Resistance (R) 4000Hz, Impedance (Z) 16000Hz, Capacitance (C) 64000Hz. Results The study demonstrated that GpEPS had no significant effect on the resistance, capacitance and impedance cells cultures, which implies that there is no significant effect on the physiological processes of L929 fibroblasts. This indicates the possibility of using GpEPS preparation in anti-cancer therapy. Conclusions In the future, following further studies (comprising in preventive and therapeutic actions), GpEPS can be safely used in anti-cancer therapy which does not cause side-effects or damage to healthy cells

Der Einfluss des Verkehrs auf die Luftqualität in Deutschland - Szenarienrechnungen für 2040

Der Verkehrssektor ist in Deutschland für einen signifikanten Anteil an der Belastung der Luft mit Schadstoffen verantwortlich. Dieses gilt insbesondere für Städte und Ballungsgebiete, aber auch in der Nähe von Hauptverkehrsadern. Schlüsselsubstanzen der Belastung sind Stickstoffoxide (NO2), Feinstaub (PM10), Kohlenmonoxid (CO) sowie flüchtige organische Verbindungen (VOCs). Als sekundärer Schadstoff ist noch das Ozon (O3) zu nennen. Im Projekt Verkehrsentwicklung und Umwelt (VEU) wurden dazu entsprechende Szenarien entwickelt, die es erlauben, den Verkehrsanteil an der zukünftigen Luftbelastung (Zieljahr 2040) für Deutschland unter unterschiedlichen Steuerungsphilosophien abzuschätzen. In VEU wurde dazu eine Modellkette aufgebaut, die Güter und Personenverkehrsmodelle mit der Fahrzeugflottenentwicklung, einem Emissionsmodell sowie am Ende der Kette einem Luftqualitätsmodell verknüpft. Die Modellkette ermöglicht es, den Verkehr in Deutschland mit hohem Detailgrad zu modellieren und entsprechend realistische Entwicklungen für die Zukunft zu erstellen. Es konnten die räumliche Verteilung der Emissionen sowie deren Auswirkungen auf die Luftqualität heute und in drei Szenarien für geänderten Verkehr untersucht werde

Ammonia emissions in Europe, part I: Development of a dynamical ammonia emission inventory

Nitrogen input from agricultural ammonia emissions into the environment causes numerous environmental and health problems. The purpose of this study is to present and evaluate an improved ammonia emission inventory based on a dynamical temporal parameterization suitable to compare and assess ammonia abatement strategies. The setup of the dynamical time profile (DTP) consists of individual temporal profiles for ammonia emissions, calculated for each model grid cell, depending on temperature, crop type, fertilizer and manure application, as well as on local legislation. It is based on the method of Skjøth et al., 2004 and Gyldenkærne et al., 2005. The method has been modified to cover the study area and to improve the performance of the emission model. To compare the results of the dynamical approach with the results of the static time profile (STP) the ammonia emission parameterizations have been implemented in the SMOKE for Europe emission model. Furthermore, the influence on secondary aerosol formation in the North Sea region and possible changes triggered through the use of a modified temporal distribution of ammonia emissions were analysed with the CMAQ chemistry transport model. The results were evaluated with observations of the European Monitoring and Evaluation Programme (EMEP). The correlation coefficient of NH3 improved significantly for 12 out of 16 EMEP measurement stations and an improvement in predicting the Normalized Mean Error can be seen for particulate NH4+ and NO3−. The prediction of the 95th percentile of the daily average concentrations has improved for NH3, NH4+ and NO3−. The NH3 concentration modelled with the STP is 157% higher in winter, and about 22% lower in early summer than the one modelled with the new DTP. Consequently, the influence of the DTP on the formation of secondary aerosols is particularly noticeable in winter, when the PM2.5 concentration is 25% lower in comparison to the use of STP for temporal disaggregation. Besides, the formation of particulate SO42− is not influenced by the use of the DTP

Joint analysis of deposition fluxes and atmospheric concentrations of inorganic nitrogen and sulphur compounds predicted by six chemistry transport models in the frame of the EURODELTAIII project

In the framework of the UNECE Task Force on Measurement and Modelling (TFMM) under the Convention on Long-range Transboundary Air Pollution (LRTAP), the EURODELTAIII project is evaluating how well air quality models are able to reproduce observed pollutant air concentrations and deposition fluxes in Europe. In this paper the sulphur and nitrogen deposition estimates of six state-of-the-art regional models (CAMx, CHIMERE, EMEP MSC-W, LOTOS-EUROS, MINNI and CMAQ) are evaluated and compared for four intensive EMEP measurement periods (25 Feb–26 Mar 2009; 17 Sep–15 Oct 2008; 8 Jan–4 Feb 2007 and 1–30 Jun 2006). For sulphur, this study shows the importance of including sea salt sulphate emissions for obtaining better model results; CMAQ, the only model considering these emissions in its formulation, was the only model able to reproduce the high measured values of wet deposition of sulphur at coastal sites. MINNI and LOTOS-EUROS underestimate sulphate wet deposition for all periods and have low wet deposition efficiency for sulphur. For reduced nitrogen, all the models underestimate both wet deposition and total air concentrations (ammonia plus ammonium) in the summer campaign, highlighting a potential lack of emissions (or incoming fluxes) in this period. In the rest of campaigns there is a general underestimation of wet deposition by all models (MINNI and CMAQ with the highest negative bias), with the exception of EMEP, which underestimates the least and even overestimates deposition in two campaigns. This model has higher scavenging deposition efficiency for the aerosol component, which seems to partly explain the different behaviour of the models. For oxidized nitrogen, CMAQ, CAMx and MINNI predict the lowest wet deposition and the highest total air concentrations (nitric acid plus nitrates). Comparison with observations indicates a general underestimation of wet oxidized nitrogen deposition by these models, as well as an overestimation of total air concentration for all the campaigns, except for the 2006 campaign. This points to a low efficiency in the wet deposition of oxidized nitrogen for these models, especially with regards to the scavenging of nitric acid, which is the main driver of oxidized N deposition for all the models. CHIMERE, LOTOS-EUROS and EMEP agree better with the observations for both wet deposition and air concentration of oxidized nitrogen, although CHIMERE seems to overestimate wet deposition in the summer period. This requires further investigation, as the gas-particle equilibrium seems to be biased towards the gas phase (nitric acid) for this model. In the case of MINNI, the frequent underestimation of wet deposition combined with an overestimation of atmospheric concentrations for the three pollutants indicates a low efficiency of the wet deposition processes. This can be due to several reasons, such as an underestimation of scavenging ratios, large vertical concentration gradients (resulting in small concentrations at cloud height) or a poor parameterization of clouds. Large differences between models were also found for the estimates of dry deposition. However, the lack of suitable measurements makes it impossible to assess model performance for this process. These uncertainties should be addressed in future research, since dry deposition contributes significantly to the total deposition for the three deposited species, with values in the same range as wet deposition for most of the models, and with even higher values for some of them, especially for reduced nitrogen

EURODELTA III exercise: An evaluation of air quality models' capacity to reproduce the carbonaceous aerosol

International audienceThe carbonaceous aerosol accounts for an important part of total aerosol mass, affects human health and climate through its effects on physical and chemical properties of the aerosol, yet the understanding of its atmospheric sources and sinks is still incomplete. This study shows the state-of-the-art in modelling carbonaceous aerosol over Europe by comparing simulations performed with seven chemical transport models (CTMs) currently in air quality assessments in Europe: CAMx, CHIMERE, CMAQ, EMEP/MSC-W, LOTOS-EUROS, MINNI and RCGC. The simulations were carried out in the framework of the EURODELTA III modelling exercise and were evaluated against field measurements from intensive campaigns of European Monitoring and Evaluation Programme (EMEP) and the European Integrated Project on Aerosol Cloud Climate and Air Quality Interactions (EUCAARI). Model simulations were performed over the same domain, using as much as possible the same input data and covering four seasons: summer (1–30 June 2006), winter (8 January – 4 February 2007), autumn (17 September- 15 October 2008) and spring (25 February - 26 March 2009). The analyses of models’ performances in prediction of elemental carbon (EC) for the four seasons and organic aerosol components (OA) for the last two seasons show that all models generally underestimate the measured concentrations. The maximum underestimation of EC is about 60% and up to about 80% for total organic matter (TOM). The underestimation of TOM outside of highly polluted area is a consequence of an underestimation of secondary organic aerosol (SOA), in particular of its main contributor: biogenic secondary aerosol (BSOA). This result is independent on the SOA modelling approach used and season. The concentrations and daily cycles of total primary organic matter (TPOM) are generally better reproduced by the models since they used the same anthropogenic emissions. However, the combination of emissions and model formulation leads to overestimate TPOM concentrations in 2009 for most of the models. All models capture relatively well the SOA daily cycles at rural stations mainly due to the spatial resolution used in the simulations. For the investigated carbonaceous aerosol compounds, the differences between the concentrations simulated by different models are lower than the differences between the concentrations simulated with a model for different seasons

Evaluation of seven chemistry transport models in the framework of EURODELTA III intercomparison exercise

The EURODELTA III (ED-III) exercise aimed to perform a comprehensive chemistry transport model inter-comparison study exploiting the data from four intensive measurement campaigns carried out by EMEP. The campaigns were held in different seasons (1–30 June 2006; 8 January–4 February 2007; 17 September–15 October 2008; 25 February–26 March 2009) thus allowing to test the influence of different meteorological conditions on models’ results. Seven models simulated the air quality over the whole Europe: CHIM (CHIMERE; version chim2013), EMEP (rv 4.1.3), LOTO (LOTOSEUROS, V1.8), CAMX (CAMx, v5.41 VBS), MINNI (version 4.7), CMAQ (V5.0.1) and RCG (v.2.1). Except CMAQ, all the models performed simulations over the same domain with the same horizontal spatial resolution. They also used the same input data (emissions, meteorology and boundary conditions) as much as possible. This work presents and discusses the behaviour of the models with regard to the criteria defined in the EU Directive on Air Quality 2008/50/EC for the air concentrations of PM10, PM2.5, O3, NO2 and SO2 and to the meteorological conditions. The wet deposition of sulphate (S) (WSOx), of oxidized and reduced nitrogen (N) (WNOx and WNHx, respectively) and the air concentrations of the deposited species were also investigated. Furthermore, a comparison of the capacities of air quality models to simulate carbonaceous aerosols (elemental (EC) and organic carbon (OC)) in Europe was conducted, given the diversity in modelling natural precursor emissions and formation and evolution of organic species, both natural and anthropogenic. In addition to EMEP data, the evaluation of models’ output included AirBase data and meteorological data from more than 2000 synoptic stations. The simulated concentrations of organic aerosol (OA) were compared to measurements available from two intensive measurement field campaigns carried out in a joint framework of EMEP and EUCAARI (the European Integrated Project on Aerosol Cloud Climate and Air Quality Interactions) project in 2008 and 2009