Influence of anthropogenic and meteorological drivers on temporal patterns of ammonia emissions from agriculture in the UK

Emissions of trace gases originating from anthropogenic activities are vital input data for chemical transport models (CTMs). Other key input datasets such as meteorological drivers, and biogeochemical and physical processes have been subject to detailed investigation and research in the recent past, while the representation of spatio-temporal aspects of emission data in CTMs has been somewhat neglected. Arguably, this has less impact on the regional to hemispheric or global scale, where the grid sizes of currently applied CTMs represent well mixed average concentrations or deposition values. Evaluating model output against ground-based observations or remote sensing results on these spatial levels may not to be overly sensitive to the temporal (and spatial) profiles of emission input data. With increasing level of detail and spatio-temporal resolution, CTMs applied to determine national or local scale air quality are likely prone to be more sensitive to the spatial and temporal patterns of anthropogenic emissions. The location and timing of emission events - for instance peaks of ammonia emissions following the spring and autumn application of manure and mineral fertilisers - may well determine local concentration or deposition episodes, while not necessarily affecting seasonal or even annual mean values. In the case of agriculture, both anthropogenic activities (e.g. manure spreading and fertilizer application) and meteorological factors (e.g. temperature and seasonality) have been investigated regarding their influence on the spatiotemporal distribution of NH3 emissions (see for instance [1], [2], [4], [5] and [6]). The discussion of results in this case will focus on the impact on the deposition of acidifying and eutrophying substances, as well as the contribution to the formation of ammonium nitrates and sulphates and hence ambient concentrations of secondary particulate matter. This paper discusses results of the application of the EMEP4UK CTM on a 5 km x 5 km resolution for the whole of the United Kingdom. To evaluate the effect of changing the temporal profiles, three different model setups, e.g. using rather coarse and potentially outdated temporal profiles of the EMEP unified model, with varying degrees of detail (in this case, a monthly profile (cf. [3]) vs. 3 hourly emission values[6]) are evaluated against the AGANET measurement network stations across the UK. The discussion of results will focus on (a) the effect of temporal emission profiles on modelled vs. measured concentration/deposition values, (b) the influence on deposition of reactive nitrogen on ecosystems near ammonia sources and (c) the magnitude of influence of anthropogenic activity vs. meteorology for the dispersion of ammonia from agriculture. The results presented in this paper will help to determine the appropriate degree of detail with regard to the temporal profiles of anthropogenic emission data, as collecting detailed statistical data on anthropogenic activities for high spatially resolved model applications can be very time consuming and expensive. In addition, the effect on improving the temporal representation of emissions influenced by both anthropogenic activities and meteorological parameters can contribute to reducing uncertainties in model results that are highly relevant for policy development, e.g. covering aspects of critical load exceedance in vulnerable ecosystems or the exceedance of concentrations of PM

Model for vindspredning af pollen

Risikoen for vindspredning af GM pollen fra raps og rug til økologiske marker med samme af-grøde er undersøgt ved hjælp af en atmosfærisk computermodel. Modellen er en videreudvikling af den danske Operationelle Meteorologiske Luftkvalitetsmodel. Modellen kan anvendes til at påvise generelle forhold hvor der er særlig stor eller lille risiko for GM-spredning til økologiske marker (f.eks. markplacering og vindforhold). Således kan modellen bruges til at undersøge risi-koen for vindspredning til de enkelte marker i landskabet. Spredningsmodellen inddrager meteo-rologiske data, afgrødens blomstringsperiode samt fysiske parametre for pollenet til beregninger af spredningen fra andre marker i landskabet. Modelberegningerne af den rumlige fordeling af rapspollen for tre lokaliteter og for fem pollen-sæsoner tyder på, at vindspredningen af pollen varierer meget pga. variationer i de meteorologiske forhold fra sæson til sæson og fra sted til sted. Specielt har den dominerende vindretning betyd-ning for koncentrationsniveauerne og fordelingen, men også den stærkt varierende turbulente tilstand af det atmosfæriske grænselag er vigtig for spredningen. Modellen har også været benyttet til at lave mere detaljerede beregninger for et testområde i Bjerringbro-Hvorslev området i Jylland. Udfra oplysninger om fordelingen af afgrøder i landskabet giver denne scenarieberegning et indblik i betydningen af fordelingen af marker i landskabet i et område med vinterrug. Generelt understøtter disse modelberegninger, at separationsafstanden mellem markerne er den mest effektive parameter for at nedsætte den relative andel af GM-pollen over en ikke-GM mark. Fordelingen af markerne i landskabet og den dominerende vindretning i det pågældende områder er dog også yderst vigtige parametre for den samlede transport af pollen. Forsøget har vist, at man, ved at inkludere de lokale meteorologiske forhold for aktuelle år evt. for en længere årrække, kan opbygge et mere detaljeret billede af spredningsrisikoen i det pågæl-dende område. Dette komplekse værktøj kan således benyttes til vurdering af f.eks. behov for særlige afstandskrav for GM-marker i specificerede områder af Danmark baseret på de lokale forhold

Future air quality and related health effects in a Nordic perspective : the possible impacts of future changes in climate, anthropogenic emissions, demography and building structure

Air pollution has been estimated to lead to ca. 10.000 premature deaths every year in the Nordic countries. The external costs related to the health effects of air pollution amounts to EUR 8-13 billion per year. Main drivers, such as changes in climate, anthropogenic emissions, building structure and demography have a vast impact on air quality-related effects on human health. The purpose of the FutureAirNordic project has been to investigate how potential future changes in main drivers will impact the assessment of air quality-related human health effects. Estimations of premature mortality due to exposure to air pollution as well as the external costs associated with the negative health effects have been analyzed. The results can contribute to improved assessments under future conditions and can be used to evaluate how policies and regulations impact the health effects of air pollution

Future Premature Mortality Due to O3, Secondary Inorganic Aerosols and Primary PM in Europe — Sensitivity to Changes in Climate, Anthropogenic Emissions, Population and Building Stock

Air pollution is an important environmental factor associated with health impacts in Europe and considerable resources are used to reduce exposure to air pollution through emission reductions. These reductions will have non-linear effects on exposure due, e.g., to interactions between climate and atmospheric chemistry. By using an integrated assessment model, we quantify the effect of changes in climate, emissions and population demography on exposure and health impacts in Europe. The sensitivity to the changes is assessed by investigating the differences between the decades 2000–2009, 2050–2059 and 2080–2089. We focus on the number of premature deaths related to atmospheric ozone, Secondary Inorganic Aerosols and primary PM. For the Nordic region we furthermore include a projection on how population exposure might develop due to changes in building stock with increased energy efficiency. Reductions in emissions cause a large significant decrease in mortality, while climate effects on chemistry and emissions only affects premature mortality by a few percent. Changes in population demography lead to a larger relative increase in chronic mortality than the relative increase in population. Finally, the projected changes in building stock and infiltration rates in the Nordic indicate that this factor may be very important for assessments of population exposure in the future

Contributions of Nordic anthropogenic emissions on air pollution and premature mortality over the Nordic region and the Arctic

This modeling study presents the sectoral contributions of anthropogenic emissions in the four Nordic countries (Denmark, Finland, Norway and Sweden) on air pollution levels and the associated health impacts and costs over the Nordic and the Arctic regions for the year 2015. The Danish Eulerian Hemispheric Model (DEHM) has been used on a 50 km resolution over Europe in tagged mode in order to calculate the response of a 30 % reduction of each emission sector in each Nordic country individually. The emission sectors considered in the study were energy production, non-industrial/commercial heating, industry, traffic, off-road mobile sources and waste management/agriculture. In total, 28 simulations were carried out. Following the air pollution modeling, the Economic Valuation of Air Pollution (EVA) model has been used to calculate the associated premature mortality and their costs. Results showed that more than 80 % of the PM2.5 concentration was attributed to transport from outside these four countries, implying an effort outside the Nordic region in order to decrease the pollutant levels over the area. The leading emission sector in each country was found to be non-industrial combustion (contributing by more than 60 % to the total PM2.5 mass coming from the country itself), except for Sweden, where industry contributed to PM2.5 with a comparable amount to non-industrial combustion. In addition to non-industrial combustion, the next most important source categories were industry, agriculture and traffic. The main chemical constituent of PM2.5 concentrations that comes from the country itself is calculated to be organic carbon in all countries, which suggested that nonindustrial wood burning was the dominant national source of pollution in the Nordic countries. We have estimated the total number of premature mortality cases due to air pollution to be around 4000 in Denmark and Sweden and around 2000 in Finland and Norway. These premature mortality cases led to a total cost of EUR 7 billion in the selected Nordic countries. The assessment of the related premature mortality and associated cost estimates suggested that non-industrial combustion, together with industry and traffic, will be the main sectors to be targeted in emission mitigation strategies in the future.Peer reviewe

Ammonia emissions from beech forest after leaf fall – measurements and modelling

Abstract. The understanding of biochemical feed-back mechanisms in the climate system is lacking knowledge in relation to bi-directional ammonia (NH3) exchange between natural ecosystems and the atmosphere. We therefore study the atmospheric NH3 fluxes during a 25 days period during autumn 2010 (21 October–15 November) for the Danish beech forest, Lille Bøgeskov, to address the hypothesis that NH3 emissions occur from deciduous forests in relation to leaf fall. This is accomplished by using observations of vegetation status, NH3 fluxes and model calculations. Vegetation status was observed using plant area index (PAI) and leaf area index (LAI). NH3 fluxes were measured using the relaxed eddy accumulation (REA) method. The REA based NH3 concentrations were compared to NH3 denuder measurements. Model calculations were obtained with the Danish Ammonia MOdelling System (DAMOS). 57.7% of the fluxes measured showed emission and 19.5% showed deposition. The mean NH3 flux was 0.087 ± 0.19 μg NH3-N m−2 s−1. A clear tendency of the flux going from negative (deposition) to positive (emission) fluxes of up to 0.96 ± 0.40 μg NH3-N m−2 s−1 throughout the measurement period was found. In the leaf fall period (23 October–8 November), an increase in the atmospheric NH3 concentrations was related to the increasing forest NH3 flux. The modelled concentration from DAMOS fits well the measured concentrations before leaf fall. During and after leaf fall, the modelled concentrations are too low. The results indicate that the missing contribution to atmospheric NH3 concentration from vegetative surfaces related to leaf fall are of a relatively large magnitude. We therefore conclude that emissions from deciduous forests are important to include in model calculations of atmospheric NH3 for forest ecosystems. Finally, diurnal variations in the measured NH3 concentrations were related to meteorological conditions, forest phenology and the spatial distribution of local anthropogenic NH3 sources. This suggests that an accurate description of ammonia fluxes over forest ecosystems requires a dynamic description of atmospheric and vegetation processes. </jats:p

Long-term residential exposure to PM2.5, PM10, black carbon, NO2, and ozone and mortality in a Danish cohort

Air pollutants such as NO2 and PM2.5 have consistently been linked to mortality, but only few previous studies have addressed associations with long-term exposure to black carbon (BC) and ozone (O3). We investigated the association between PM2.5, PM10, BC, NO2, and O3 and mortality in a Danish cohort of 49,564 individuals who were followed up from enrollment in 1993–1997 through 2015. Residential address history from 1979 onwards was combined with air pollution exposure obtained by the state-of-the-art, validated, THOR/AirGIS air pollution modelling system, and information on residential traffic noise exposure, lifestyle and socio-demography. We observed higher risks of all-cause as well as cardiovascular disease (CVD) mortality with higher long-term exposure to PM2.5, PM10, BC, and NO2. For PM2.5 and CVD mortality, a hazard ratio (HR) of 1.29 (95% CI: 1.13–1.47) per 5 μg/m3 was observed, and correspondingly HRs of 1.16 (95% CI: 1.05–1.27) and 1.11 (95% CI: 1.04–1.17) were observed for BC (per 1 μg/m3) and NO2 (per 10 μg/m3), respectively. Adjustment for noise gave slightly lower estimates for the air pollutants and CVD mortality. Inverse relationships were observed for O3. None of the investigated air pollutants were related to risk of respiratory mortality. Stratified analyses suggested that the elevated risks of CVD and all-cause mortality in relation to long-term PM, NO2 and BC exposure were restricted to males. This study supports a role of PM, BC, and NO2 in all-cause and CVD mortality independent of road traffic noise exposure