Future Scenarios of Nitrogen in Europe

The future effects of nitrogen in the environment will depend on the extent of nitrogen use and the practical application techniques of nitrogen in a similar way as in the past. Projections and scenarios are appropriate tools for extrapolating current knowledge into thefuture. However,these tools will not allow future system turnovers to be predicted. Approaches• In principle, scenarios of nitrogen use follow the approaches currently used for air pollution,climate ,or ecosystem projections. Short term projections (to 2030) are developed using a ‘baseline’ path of development,which considers abatement options that are consistent with European policy. For medium-term projections (to 2050) and long-term projections, the European Nitrogen Assessment (ENA) applies a ‘storyline’ approach similar to that used in the IPCC SRES scenarios. Beyond 2050 in particular, such story lines also take into account technological and behavioral shift s.Key findings/state of knowledge• The ENA distinguishes between driver-oriented and effect-oriented factors determining nitrogen use. Parameters that cause changes in nitrogen fixation or application are called drivers. In a driver-based approach, it is assumed that any variation of these parameters will also trigger a change in nitrogen pollution. In an effect-based approach, as the adverse effects of nitrogen become evident inthe environment, introduction of nitrogen abatement legislation requiring the application of more efficient abatement measuresis expected. This approach needs to rely on a target that is likely to be maintained in the future (e.g.human health). Nitrogen abatement legislation basedon such targets will aim to counter any growth in adverse environmental effects that occur as a result of increased nitrogen application.• For combustionand industry, technical fixes forabatement are available. Allscenarios agree in projecting a decrease in NOx emissions.Yet agricultural nitrogen use is expected to remain the leading cause of nitrogen release to the environment, as options to reduce emissions are limited. Thus, major changes will occur only if the extent of agricultural production changes, which may possibly be triggered by decreasing population numbers in Europe.The scenarios presented here project modest changes in NH 3 and N 2 O emissions, or nitrateleaching, but do not agree on the direction of these changes.•Agricultural activity (and thus nitrogen loads to the environment) may decrease strongly if the European population adopts a healthier‘low meat’ diet leading to lower nitrogenlosses related to animal husbandry. Change to a ‘healthy diet’ across the EU, which consists of 63% less meat and eggs, would reduce ammonia emissions from animal production by 48%. However, if an agricultural area previously used for animal feed production is utilized for biofuel crops, additional nitrogen fertilizer maybe required, which will partially offset reductions of nitrogen leakage to the environment. Major uncertainties/challenges• International trade in nitrogen-containing goods (agricultural as well as industrial) represents a key uncertainty and is difficult to project. Estimating the demand for such goods for Europe alone may not at all reflect European production and related environmental effects. The industrial use of nitrogen is alsovery poorly understood, but it is expected to continue to grow considerably. The respective environmental impacts of such products cannot be clearly discerned from statistical information.Recommendations• Scenarios need to be continuously updated in terms of economic, technical, and societal trends to reflect improved understanding of these factors. Using nitrogen budgets as tools could improve the consistency of scenarios.JRC.DDG.H.2-Climate change and air qualit

ECLAIRE third periodic report

The ÉCLAIRE project (Effects of Climate Change on Air Pollution Impacts and Response Strategies for European Ecosystems) is a four year (2011-2015) project funded by the EU's Seventh Framework Programme for Research and Technological Development (FP7)

ECLAIRE: Effects of Climate Change on Air Pollution Impacts and Response Strategies for European Ecosystems. Project final report

The central goal of ECLAIRE is to assess how climate change will alter the extent to which air pollutants threaten terrestrial ecosystems. Particular attention has been given to nitrogen compounds, especially nitrogen oxides (NOx) and ammonia (NH3), as well as Biogenic Volatile Organic Compounds (BVOCs) in relation to tropospheric ozone (O3) formation, including their interactions with aerosol components. ECLAIRE has combined a broad program of field and laboratory experimentation and modelling of pollution fluxes and ecosystem impacts, advancing both mechanistic understanding and providing support to European policy makers. The central finding of ECLAIRE is that future climate change is expected to worsen the threat of air pollutants on Europe’s ecosystems. Firstly, climate warming is expected to increase the emissions of many trace gases, such as agricultural NH3, the soil component of NOx emissions and key BVOCs. Experimental data and numerical models show how these effects will tend to increase atmospheric N deposition in future. By contrast, the net effect on tropospheric O3 is less clear. This is because parallel increases in atmospheric CO2 concentrations will offset the temperature-driven increase for some BVOCs, such as isoprene. By contrast, there is currently insufficient evidence to be confident that CO2 will offset anticipated climate increases in monoterpene emissions. Secondly, climate warming is found to be likely to increase the vulnerability of ecosystems towards air pollutant exposure or atmospheric deposition. Such effects may occur as a consequence of combined perturbation, as well as through specific interactions, such as between drought, O3, N and aerosol exposure. These combined effects of climate change are expected to offset part of the benefit of current emissions control policies. Unless decisive mitigation actions are taken, it is anticipated that ongoing climate warming will increase agricultural and other biogenic emissions, posing a challenge for national emissions ceilings and air quality objectives related to nitrogen and ozone pollution. The O3 effects will be further worsened if progress is not made to curb increases in methane (CH4) emissions in the northern hemisphere. Other key findings of ECLAIRE are that: 1) N deposition and O3 have adverse synergistic effects. Exposure to ambient O3 concentrations was shown to reduce the Nitrogen Use Efficiency of plants, both decreasing agricultural production and posing an increased risk of other forms of nitrogen pollution, such as nitrate leaching (NO3-) and the greenhouse gas nitrous oxide (N2O); 2) within-canopy dynamics for volatile aerosol can increase dry deposition and shorten atmospheric lifetimes; 3) ambient aerosol levels reduce the ability of plants to conserve water under drought conditions; 4) low-resolution mapping studies tend to underestimate the extent of local critical loads exceedance; 5) new dose-response functions can be used to improve the assessment of costs, including estimation of the value of damage due to air pollution effects on ecosystems, 6) scenarios can be constructed that combine technical mitigation measures with dietary change options (reducing livestock products in food down to recommended levels for health criteria), with the balance between the two strategies being a matter for future societal discussion. ECLAIRE has supported the revision process for the National Emissions Ceilings Directive and will continue to deliver scientific underpinning into the future for the UNECE Convention on Long-range Transboundary Air Pollution

Past and Future Exceedances of Nitrogen Critical Loads in Europe

Critical loads of acidity and nutrient nitrogen — simple measures of the sensitivity of ecosystems to deposition — have been widely used for setting emission reduction targets in Europe. In contrast to sulfur, the emissions of nitrogen compounds remain high in the future. This is also true for the exceedances of critical loads until 2010. Looking further into the future, climate change is likely to influence ecosystem sensitivity, and thus critical loads. It is shown that higher temperatures, changed precipitation patterns, and modified net primary production mainly increase critical loads, except in mountainous and arid regions. Using consistent scenarios of climate change and air pollution from a recently completed European study (AIR-CLIM), it is shown that the exceedances in 2100 of the critical loads are declining in comparison to 2010. However, exceedances of critical loads of nutrient nitrogen remain substantial, even under the most stringent scenario. This confirms the increasing role nitrogen plays in environmental problems in comparison to sulfur. Thus research should focus on the effects of nitrogen in the environment, especially under conditions of climate change, to support nitrogen-emission mitigating policies. This not only reduces acidification and eutrophication, but also helps curb the formation of tropospheric ozone

Trends in ecosystem and health responses to long-rangetransported atmospheric pollutants - ICP Waters report125/2015

The aim of this trend report is to assess the effectiveness of air pollution policies under the Convention on Long-range Transboundary Air Pollution (LRTAP), and to document progress and identify remaining challenges. Trends in environmental and health responses to long-range transported air pollution are presented, primarily focusing on 1990 to 2012 and on Europe, with additional data from North America and the Arctic region. Air pollutants included in the report are sulphur and nitrogen as acidifying agents, nutrient-nitrogen, ground-level ozone, particulate matter (PM), heavy metals and persistent organic pollutants (POPs). The results are from work done under the bodies of the Working Group on Effects of the LRTAP Convention, i.e. ICP Integrated Monitoring, ICP Forests, ICP Materials, ICP Modelling and Mapping, ICP Vegetation, ICP Waters, JEG Dynamic Modelling and the Task Force on Health. The European Monitoring and Evaluation Programme (EMEP) and the Arctic Monitoring and Assessment Programme (AMAP) also contributed